BACKGROUND

Certain CC chemokines including ligands for the HIV-1 coreceptor CCR5 are associated with suppression of HIV-1 infection. Whether the release of these chemokines from lymphocytes influences treatment outcome in children receiving antiretroviral therapy is not known.

METHODS

A study of 175 HIV-infected children in Rio de Janeiro, Brazil was conducted to compare clinical measures and HIV-suppressive chemokine release. Clinical measures including %CD4 T cells, viral loads, and antiretroviral drug-resistant mutations were obtained. Chemokine release was measured in cultures of peripheral blood mononuclear cells collected from 135 children before or after receiving therapy. Chemokine levels were compared between subject groups stratified according to clinical measures and treatment regimen (1-2, 3-4, or no antiretrovirals) extant at the time of cell sample collection.

RESULTS

Mean viral loads did not vary significantly between treatment groups although there were significant differences in %CD4 T cells. Virus from children taking 3-4 antiretrovirals had significantly more drug-resistant mutations than did virus from those receiving 1-2 drugs. Among antiretroviral-treated children, there was a significant direct relationship between %CD4 T cells and MIP-1alpha/CCL3 and macrophage-derived chemokine/CCL22 production. In addition, there was a significant inverse relationship between viral load and MIP-1alpha production in patients receiving 3-4 antiretrovirals. Greater recovery of %CD4 T cells after therapy was associated with higher MIP-1alpha and macrophage-derived chemokine production at baseline.

CONCLUSIONS

The production of HIV-suppressive chemokines is associated with better outcome in children receiving antiretroviral regimens in settings where drug-resistant mutations are prevalent. Such information may provide insights for the design of treatment strategies for pediatric HIV infection under similar circumstances.

Macrophage-derived chemokine (MDC) CCL22 is a potent chemoattractant for Th2 cells and has been implicated in Th2-predominant allergic inflammation. In the present study, we demonstrated that basophils produce MDC in response to monomeric IgE. In trinitrophenyl (TNP)-IgE transgenic mice, serum levels of MDC were persistently higher than in wild-type mice. The i.v. administration of TNP-specific IgE to wild-type mice transiently induced an elevation in serum MDC, which appeared to be mediated by Fc epsilonRI, as no increase in serum MDC was observed after IgE administration in FcRgamma (-/-) mice. However, the IgE-mediated increase in MDC was observed in mast cell-deficient mice. Freshly isolated bone marrow cells and bone marrow-derived basophils secreted MDC in response to TNP-IgE without Ag stimulation. Furthermore, MDC production was not observed in bone marrow-derived basophils isolated from FcRgamma (-/-) mice. IgE activated Lyn and ERK 1/2 in bone marrow-derived basophils. Treatment of TNP-IgE transgenic mice with a basophil-depletion Ab (Ba103) resulted in decreased serum MDC levels. Thus, IgE appears to be capable of stimulating basophils to produce MDC in the absence of a specific Ag, which may contribute to IgE-mediated and/or Th2-predominant allergic inflammation.

OBJECTIVE

To identify the function of ST2 and explore the role of IL-33/ST2 signaling in regulating the pro-allergic cytokine production in human corneal epithelial cells (HCECs).

METHODS

Human corneal tissues and cultured primary HCECs were treated with IL-33 in different concentrations without or with different inhibitors to evaluate the expression, location and signaling pathways of ST2 in regulating production of pro-allergic cytokine and chemokine. The expression of mRNA was determined by reverse transcription and real time PCR, and protein production was measured by enzyme-linked immunosorbent assay (ELISA), immunohistochemical and immunofluorescent staining. ST2 protein was detected in donor corneal epithelium, and ST2 signal was enhanced by exposure to IL-33.

RESULTS

IL-33 significantly stimulated production of pro-allergic cytokines thymic stromal lymphopoietin (TSLP) and chemokine (CCL2, CCL20, CCL22) in HCECs at both mRNA and protein levels. These stimulated productions of pro-allergic mediators by IL-33 were blocked by ST2 antibody or soluble ST2 protein (P<0.05). Interestingly, the IκB-α inhibitor BAY11-7082 or NF-κB activation inhibitor quinazoline blocked NF-κB p65 protein nuclear translocation, and also suppressed the productions of these pro-allergic cytokines and chemokine induced by IL-33.

CONCLUSIONS

These findings demonstrate that IL-33/ST2 signaling plays an important role in regulating IL-33 induced pro-allergic responses. IL-33 and ST2 could become novel molecular targets for the intervention of allergic diseases in ocular surface.

We report here that human B cells produce thymus and activation-regulated chemokine (TARC/CCL17) and macrophage derived chemokine (MDC/CCL22) if stimulated with anti-CD40 and IL-4. The production was determined by both protein and mRNA level using specific ELISA and semi-quantitative RT-PCR methods. Since the ligand of the TARC and MDC is CCR4, which is specifically expressed on Th2 type T cells, the production of these CC chemokines is likely to play important roles in the T cell and B cell interaction. Consistent with this, ovalbumin (OVA) specific IgE levels, which reflect the T-B cell interaction, are significantly correlated with the amounts of TARC and MDC in sera. Furthermore, we found that TARC and MDC levels are significantly increased in the sera obtained from patients with atopic dermatitis, and that the amounts are correlated with the severity of atopic dermatitis. Since CD40 ligand and IL-4 are produced by activated T helper cells, these results indicate that TARC and MDC produced by B cells play important roles in the production of antigen specific IgE by the T-B cell interaction and in the pathogenesis of allergic disease.

OBJECTIVE

Macrophage-derived chemokine (MDC/CCL22) is recognized as a T-helper (Th) 2-type chemokine. Both malignant and tuberculous pleural effusions are typically lymphocytic pleural effusions. Tuberculous pleural effusions have a more polarized Th1 reaction than malignant effusions, which are predominantly Th2 in nature. The aim of this study was to compare the levels of MDC in malignant pleural effusions with those in tuberculous pleural effusions to help delineate the role of MDC in Th2 versus Th1 effusions.

METHODS

Forty-three patients with pleural effusions (32 malignant, 11 tuberculous) were studied. The concentration of MDC in the pleural effusion was measured by ELISA.

RESULTS

The median concentration of MDC was lower in malignant pleural effusions than in tuberculous pleural effusions (P < 0.005).

CONCLUSIONS

MDC has been reported to both promote and suppress antitumour immunity. The low concentration of MDC in malignant effusions is likely to minimise its antitumour activity but the precise role of MDC in malignant and tuberculous effusions needs to be investigated further.

OBJECTIVE

The aim of the study was to assess possible binding of a mixture of constitutive Hsc70 and inducible Hsp70 forms (HSP70) to Toll-like receptor (TLR) 4 and CD91 receptors on decidual CD1a(+) dendritic cells (DCs) and their influence on DCs maturation status.

METHODS

Immunohistology and immunofluorescence of paraffin-embedded first trimetester and term pregnancy decidua were performed together with flow cytometry detection of antigens in DCs after stimulation of decidual mononuclear cells with HSP70.

RESULTS

Hsc70 and Hsp70 labeling revealed intracellular and nuclear staining in trophoblast cells. The numbers of Hsc70(+) and Hsp70(+) cells of decidual tissue were higher in early pregnancy decidua than in decidua at term. HSP70 binds CD91 and TLR4 receptors on CD1a(+) DCs and increased the expression of CD83, HLA-DR, CD80, and CD86, but decreased CC receptor (CCR) 5. HSP70 increased CC ligand (CCL) 3 and CCL22. HSP70 in the concentration of 1 μg/mL increased the percentage of interferon-γ and interleukin (IL)-15-expressing cells over the cells expressing IL-4.

CONCLUSIONS

HSP70 binds CD91 and TLR4 on decidual CD1a(+) DCs, causes their maturation, and increases IL-15 in the context of Th1 cytokine/chemokine domination, which could support immune response harmful for ongoing pregnancy.

BACKGROUND

When sensitized epicutaneously and challenged orally with ovalbumin, Balb/c mice develop allergen-induced diarrhea. As mast cells play important roles in diarrhea, we studied whether allergic diarrhea could be alleviated with imatinib mesylate.

METHODS

Balb/c mice were sensitized and challenged with ovalbumin and treated orally with imatinib. Cytokine mRNA expressions were determined with quantitative RT-PCR and numbers of small intestinal mast cells determined by staining for chloroacetate esterase and mucosal mast cell protease-1. Immunofluorescence staining was used to assess the intestinal CCL1 expression.

RESULTS

Ovalbumin-sensitized and challenged Balb/c mice developed diarrhea, which was associated with increased number of mast cells and expression of interleukin (IL)-4 and -13, and chemokines CCL1 and CCL17 in the small intestine. Treatment with imatinib reduced the incidence of diarrhea, inhibited the development of mastocytosis and jejunal mRNA expression of IL-13, CCL1, CCL17 and CCL22. Mast cell-deficient W/W(-V) mice, and surprisingly, also their mast cell-competent control (+/+) littermates failed to develop diarrhea as a response to ovalbumin. This strain-dependent difference was associated with the inability of +/+ and W/W(-V) mice to increase the number of intestinal mast cells and expression of IL-4, IL-13, CCL1 and CCL17 after ovalbumin challenge.

CONCLUSIONS

Development of allergic diarrhea is associated with the ability of mice to develop intestinal mastocytosis. Imatinib inhibited the development of intestinal mastocytosis, reduced the incidence of diarrhea, and reduced the expression of IL-13, CCL1, and CCL17. Targeting intestinal mast cells could be a feasible approach to treat allergic diarrhea.

Asthma and allergies are today the most common chronic diseases in children and the leading causes of school absences, chronic medication usage, emergency department visits and hospitalizations, which affect all members of the family and represent a significant societal and scientific challenge. These highly prevalent disorders are thought to originate from immune distortion in early childhood, but the etiology and heterogeneity of the disease mechanisms are not understood, which hampers preventive initiatives and makes treatment inadequate. The objective of this thesis is to investigate the presence of an early life disease activity prior to clinical symptoms to understand the anteceding pathophysiological steps towards childhood asthma and allergy. The thesis is built on seven studies from the Copenhagen Prospective Studies on Asthma in Childhood (COPSAC2000) birth cohort examining biomarkers of disease activity in 411 asymptomatic neonates in cord blood (I-II), urine (III), exhaled breath (IV-V) and infant lung function (VI-VII) in relation to the subsequent development of asthma and allergy during the first seven years of life. In papers I-II, we studied cord blood chemokines and 25(OH)-vitamin D, which represent a proxy of the inborn immature immune system, the intrauterine milieu, and the maternal immune health during pregnancy. High levels of the Th2-related chemokine CCL22 and high CCL22/CXCL11 ratio were positively correlated with total IgE level during preschool age (II). This suggests an inborn Th2 skewing of the immune system in healthy newborns subsequently developing elevated total IgE antibodies, which is considered to increase the risk of asthma and allergies later in life. Additionally, deficient cord blood 25(OH)-vitamin D levels were associated with a 2.7-fold increased risk of recurrent wheeze at age 0-7 years (I). Together, these findings support the concept that early life immune programming in the pre-symptomatic era plays an essential role for promotion of or protection against asthma and allergies. Therefore, preventive initiatives to restore immune health, such as vitamin D supplementation, should be directed to the fetus and the earliest postnatal life. The eosinophil granulocyte has a major role in the allergic inflammatory cascade and eosinophilia is considered a hallmark of many allergic phenotypes. In paper III, we examined neonatal urinary biomarkers including eosinophil protein X (u-EPX), which is contained in the eosinophil granules. Elevated u-EPX in asymptomatic neonates was associated with development of allergic sensitization and nasal eosinophilia, but not with wheezing or asthma (III). These findings suggest the presence of an ongoing low-grade disease process in early life characterized by eosinophil activation prior to appearance of allergy-related conditions. In papers IV-V, we investigated perinatal and genetic predictors of neonatal fractional exhaled nitric oxide (FeNO) and the relationship between neonatal FeNO and wheezing later in child-hood. The a priori selected determinants encompassed asthma genetic risk variants, anthropometrics, demographics, socioeconomics, parental asthma and allergy, maternal smoking, paracetamol and antibiotic usage during pregnancy, and neonatal bacterial airway colonization. Among those, only the DENND1B risk allele and paternal history of asthma and allergy were associated with increased FeNO values (V) suggesting that raised FeNO in neonatal life is primarily an inherited trait. The neonatal FeNO levels were widely dispersed (1-67 ppb) and children with values in the upper quartile were at increased risk of recurrent wheezing in early childhood, but not persistent wheezing, reduced lung function or allergy-related endpoints (IV). This suggests that elevated neonatal FeNO represents an early asymptomatic low-grade disease process other than congenitally small airway calibre contributing to a transient wheezing phenotype. Reduced lung function in neonates is associated with wheezing and asthma proneness, but it is unknown if such host factor also confers a risk of acute bronchiolitis, which is considered an index event of asthma persisting into school age. In paper VI, we investigated neonatal forced flow, volume, and responsiveness to methacholine in relation to occurrence of acute severe bronchiolitis at age 0-2 years. Children developing bronchiolitis had a 2.5-fold increased bronchial responsiveness as neonates (VI) suggesting a preexisting joint propensity of the airways to react adversely to common respiratory viruses and to develop asthma. This finding proposes airway hyperresponsiveness as yet another marker of low-grade disease activity among asymptomatic neonates on a trajectory towards childhood asthma. In paper VII, we examined whether neonates with impaired pulmonary capacity also had signs of systemic inflammation prior to clinical symptoms. Reduced FEV0.5 was significantly associated with elevated serum hs-CRP and other blood inflammatory markers (VII) suggesting presence of systemic low-grade inflammation from the beginning of life. Chronic low-grade inflammation is a common nominator of virtually all the major non-communicable welfare diseases (NCDs) of modernity whereof asthma and allergies are the earliest debuting disorders. The novel finding of systemic low-grade inflammation among neonates at increased risk of asthma and allergy, therefore implies that exploring the origins of asthma and allergy may also unravel disease mechanisms involved in other NCDs. In conclusion, the series of papers presented in this thesis (I-VII) evidence the presence of a pre-symptomatic disease process measurable in several body compartments, which supports the notion of low-grade disease activity in early life as a generic trait among neonates developing asthma and allergy. This hypothesis piggybacking on single biomarker assessments could be enforced and refined by applying novel global omics approaches. In particular, metabolomic analyses of serum, urine, and airway lining fluid from neonates as well as neonatal VOC profiling of exhaled breath may facilitate a broader understanding of the early low-grade disease activity preceding clinical symptoms. Disentangling the introductory pathophysiological mechanisms and underlying endotypes of disease is paramount for generating successful preventive measures to alleviate the major global burden of asthma, allergy, and other NCDs of modern time.

Immunotherapies have emerged as promising complementary treatments for ovarian cancer (OC), but its effective and direct role on OC cells is unclear. This study examined the combinatory effects of the protein aggregate magnesium-ammonium phospholinoleate-palmitoleate anhydride, known as P-MAPA, and the human recombinant interleukin-12 (hrIL-12) on cell migration/invasion, apoptosis, toll-like receptor (TLR)-mediated inflammation, and cytokine/chemokine profile in human OC cell line SKOV-3. P-MAPA and IL-12 showed cancer cell toxicity under low doses after 48 h. Although apoptosis/necrosis and the cell cycle were unchanged by the treatments, P-MAPA enhanced the sensitivity to paclitaxel (PTX) and P-MAPA associated with IL-12 significantly reduced the migratory potential and invasion capacity of SKOV-3 cells. P-MAPA therapy reduced TLR2 immunostaining and the myeloid differentiation factor 88 (MyD88), but not the TLR4 levels. Moreover, the combination of P-MAPA with IL-12 attenuated the levels of MyD88, interferon regulatory factor 3 (IRF3) and nuclear factor kappa B (NF-kB p65). The IL-12 levels were increased and P-MAPA stimulated the secretion of cytokines IL-3, IL-9, IL-10, and chemokines MDC/CCL22 and, regulated on activation, normal T cells expressed and secreted (RANTES)/CCL5. Conversely, combination therapy reduced the levels of IL-3, IL-9, IL-10, MDC/CCL22, and RANTES/CCL5. Collectively, P-MAPA and IL-12 reduce cell dynamics and effectively target the TLR-related downstream molecules, eliciting a protective effect against chemoresistance. P-MAPA also stimulates the secretion of anti-inflammatory molecules, possibly having an immune response in the OC microenvironment.

Spinal tuberculosis is a condition characterized by massive resorption of the spinal vertebrae due to the infection with Mycobacterium tuberculosis (Mtb). However, the pathogenesis of spinal tuberculosis has not been established because it was almost completely eradicated by the establishment of antibiotic treatment in the mid-20th century. In this study, we investigated the inflammatory responses of human multinucleated osteoclasts infected with virulent Mtb strain. We found that the intracellular Mtb infection of multinuclear osteoclasts resulted in the rapid growth of Mtb and an osteolytic response, rather than inflammation. In response to Mtb infection, the mononuclear osteoclast precursors produced proinflammatory cytokines including tumor necrosis factor (TNF)-α, an intrinsic characteristic they share with macrophages. In contrast, highly fused multinucleated osteoclasts incapacitated the production of these cytokines. Instead, the intracellular Mtb inside multinuclear osteoclasts escaped from the endosome/phagosome, leading to a different pattern of osteoclast activation, with the production of chemokines such as CCL5, CCL17, CCL20, CCL22, CCL24, and CCL25. Moreover, intracellular infection with an avirulent Mtb strain resulted in diminished production of these chemokines. These findings indicate that intracellular Mtb infection in multinuclear osteoclasts reprograms osteoclast development via the dysregulation of cytokines and chemokines.

To investigate an immunomodulatory role for vitamin D in pregnancy we used mice raised on vitamin D-sufficient (SUFF), or -deficient (DEF) diets. At embryonic day 14, pregnant mice received intraperitoneal injection of lipopolysaccharide (LPS) or vehicle for 24h, with age-matched non-pregnant mice as controls. In non-pregnant mice, 6 serum analytes (IL-1β, IL-18, MDC/CCL22, MIP-1α/CCL3, EGF, IgA) were lower in DEF mice. In pregnant DEF mice only GH was higher. In non-pregnant mice LPS induced 28 analytes, with 5 (IL-18, IP-10/CXCL10, MCP-1/CCL2, MIP-1β/CCL4, MIP-3β/CCL19) being highest in DEF mice. In pregnant SUFF mice 16 serum analytes increased with LPS, and 6 of these (IP-10/CXCL10, MCP-1/CCL2, SAP, TIMP-1, VCAM-1, vWF) were higher and 1 (GCP-2/CXCL6) lower in DEF mice. Parallel analysis of placental mRNAs showed elevated mRNA for Il-6, Ccl2 and Cxcl10 in placentae from male and female fetuses in LPS-DEF mice. However, LPS-induced expression of Ifnγ, Tnfα, and Cxcl6 was only observed in female placentae from DEF mice. LPS-DEF mice also showed smaller litter sizes relative to control SUFF mice. Numbers of female fetuses per dam were significantly lower for DEF mice with or without LPS challenge. LPS had no effect on numbers of male fetuses from DEF mothers, but significantly decreased male fetuses from SUFF mothers. These data indicate that vitamin D is an important component of anti-inflammatory immune responses during pregnancy, with the placenta and fetal sex playing pivotal roles in this process.

BACKGROUND

Mycosis fungoides (MF) is a T cell neoplasm with elevation of serum Th2 chemokines. Although interferon-gamma (IFN-gamma) administration and narrowband-UVB (NB-UVB) phototherapy are used for the treatment of MF, a combination therapy of these two modalities is not fully established.

OBJECTIVE

To define whether the combination of IFN-gamma and NB-UVB affects the balance of serum levels of Th1 and Th2 chemokines in patients with MF.

METHODS

Twelve patients with MF received intravenous or intramuscular injections of recombinant IFN-gamma (rIFN-gamma) or natural IFN-gamma (nIFN-gamma) in combination with NB-UVB phototherapy. As control, three MF patients were treated with NB-UVB monotherapy. At the beginning and cessation of therapy, the concentrations of serum Th2 chemokines, TARC/CCL17 and MDC/CCL22, and Th1 chemokines, IP-10/CXCL10 and MIG/CXCL9 were measured by ELISA.

RESULTS

Before treatment, not only Th2 chemokines but also Th1 chemokines were elevated in the patients. Whereas no significant changes were observed in the levels of TARC and MDC, IP-10 and MIG were further elevated by the combination of IFN-gamma and NB-UVB. On the other hand, NB-UVB monotherapy did not change the level of either Th1 or Th2 chemokine.

CONCLUSIONS

The combination of IFN-gamma and NB-UVB elevated serum Th1 chemokines but unaffected Th2 chemokines. Since NB-UVB monotherapy could not affect the chemokine levels, the effect of the combination therapy is attributable to IFN-gamma. Given the role of Th1 chemokines for tumor-attacking T cell recruitment at the early stage of MF, the therapy may exert a beneficial effect for early MF.

The disequilibrium of local immune microenvironment is an essential element during tumorigenesis.

By conducting real-time polymerase chain reaction, we identified the mRNA level of immune factors, FoxP3 (forkhead box protein P3), CCL22/CCR4 (chemokine (C-C motif) ligand 22/CC chemokine receptor 4), OX40L/OX40 (tumor necrosis factor superfamily member 4/tumor necrosis factor receptor superfamily member 4) and Smad3 (SMAD family member 3) in neoplastic foci and its periphery tissues from 30 cases of squamous cervical carcinoma and 20 cases of normal cervix.

The FoxP3, CCL22 and CCR4 mRNA level in local immune microenvironment of normal cervix was lower than that in cervical cancer. While OX40L, OX40 and Smad3 mRNA level profile in normal cervix was higher than that in cervical cancer. Beyond individual effect, the pairwise positive correlations were demonstrated among the mRNA level of FoxP3, CCL22 and CCR4. The mRNA level of OX40 negatively correlated with CCL22, but positively correlated with Smad3. Moreover, the mRNA level of FoxP3 and CCL22 was increased while Smad3 was decreased in cervical tissue with HPV (human papilloma virus) infection.

Our data yields insight into the roles of these immune factors in cervical carcinogenesis. It may therefore be that, in microenvironment of cervical squamous cell carcinoma, along with the context of HPV infection, negative immune regulators FoxP3, CCL22 and CCR4 might overwhelm positive immune factors OX40L, OX40 and Smad3, giving rise to an immunosuppressive status and promote the progression of cervical carcinogenesis.

Not applicable.

Monocyte-derived dendritic cells (DCs) were used as an in vitro model of myeloid DCs in order to determine a minimum marker pattern with which to characterize and distinguish different stages of DC activation and maturation. Phenotypic changes induced on immature DCs by two prototypic stimuli, poly I:C and CD40 ligation, were first examined. Both elicited HLA-DR, CD40, CD86 and CXCR4 upregulation, and CCR5 downregulation, but only CD40 ligand-stimulated DCs became CD83(+)\CCR7(+), whereas poly I:C-stimulated DCs expressed lower CD83 levels and were mostly CCR7(--). CD40 ligation and poly I:C elicited increased production of inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor-alpha, of IL-10 and the CCL5 chemokine, but profiles differed as to higher IL-10, IL-12 and CCL22 (a CCR4 ligand important for T cell recruitment) levels for the former, and of CCL4 and CCL5 for the latter. Thus, a limited set of phenotypic markers, cytokine and chemokine production assays, may be used to distinguish the three stages in the life of DCs: immaturity, activation and full maturation. The ability of purified protein derivative-loaded DCs to stimulate autologous T cells to produce IL-2, IL-4 and interferon-gamma indeed depended on their activation stage and endocytic activity, which decreased upon maturation. We then examined whether ligation of CD4, CCR5 and\or CXCR4, the receptor and coreceptors of human immunodeficiency virus envelope gp120, respectively, affected DC activation or maturation, neither a monoclonal antibody to the gp120-binding site on CD4 nor CCL5 nor CXCL12, the natural ligands of CCR5 and CXCR4, respectively, nor gp120 altered the DC activation and maturation processes.

To identify immune factors present during the acute rash phase of measles and associations with outcome and human immunodeficiency virus type 1 (HIV-1) coinfection, we measured the plasma levels of 22 cytokines and chemokines in Zambian children hospitalized with measles (n = 148) and control children (n = 44). Children with measles had higher levels of innate cytokines tumor necrosis factor (TNF) α, interleukin 1β (IL-1β), interleukin 18, and interleukin 6; chemokines CCL2, CCL4, CCL11, CCL22, CXCL8, and CXCL10; and T-cell cytokines interferon γ, and interleukin 2, 10, and 17. Children who died in the hospital had higher levels of TNF-α, IL-1β, interleukin 12p70; CCL2, CCL4, CCL13, CCL17, CXCL8, CXCL10; and interleukin 2 and interferon γ than children who survived, and lower levels of interleukin 4. Children coinfected with HIV-1 had higher levels of TNF-α and IL-1β than HIV-uninfected children with measles, and lower levels of interleukin 4 and 5. Therefore, acute measles was characterized by activation of macrophages and T cells producing type 1, but not type 2, cytokines, which was more pronounced in fatal disease.

BACKGROUND

Maculopapular exanthema has been reported to be the most frequently drug-induced cutaneous reaction. Although T lymphocytes are involved in the pathomechanism of this disease, little is know about the recruitment of these cells to the skin.

OBJECTIVE

The aim of this work is to study the role of the chemokines TARC/CCL17 and MDC/CCL22 in the lymphocyte trafficking to affected skin in drug-induced exanthemas.

METHODS

Real-time PCR was performed to quantify gene expression levels of CCL17, CCL22 and their receptor CCR4 in lesional skin biopsies and in peripheral blood mononuclear cells from patients. CCL27 and CCL22 proteins were detected in the skin by immunochemistry. Protein expression of CCR4 was determined by flow cytometry in peripheral blood lymphocytes. Functional migration assays to CCL17 and CCL22 were assessed to compare the migratory responses of peripheral blood lymphocytes from patients and healthy subjects.

RESULTS

CCL17 and CCL22 were up-regulated in maculopapular exanthema-affected skin. CCR4 mRNA levels and protein expression were increased in peripheral blood mononuclear cells during the acute phase of the disease. The increased expression of the receptor was consistent with a higher response of peripheral blood lymphocytes to CCL17 and CCL22 compared with the migratory response in healthy donors.

CONCLUSIONS

TARC/CCL17 and MDC/CCL22 might cooperate in attracting T lymphocytes to skin in drug-induced maculopapular exanthemas.

BACKGROUND

The lesional skin of patients with atopic dermatitis has an increased number of type 2 helper T (TH2) cells in the dermis and is superficially colonized by Staphylococcus aureus. The purpose of this study was to determine the effects of peptidoglycan (PEG) from S aureus on TH2 cell induction in murine skin.

METHODS

Mice were sensitized with house dust mite antigen (MA) by topical application to barrier-disrupted abdominal skin. Seven days after sensitization, PEG was applied to the barrier-disrupted dorsal skin. After a further 3 days, C-C chemokine receptor type 4-positive (CCR4+) cells were counted in the PEG-treated skin.The production of chemokine (C-C) motif ligand 17 (CCL17) (thymus- and activation-regulated chemokine) and CCL22 (macrophage-derived chemokine) in the skin was investigated using reverse transcriptase polymerase chain reaction and immunohistological analysis.

RESULTS

Application of PEG to the dorsal skin of MA-sensitized mice led to a significant increase in the number of cells expressing CCR4 in the dermis. The skin of PEG-treated mice showed an increased level of CCL17 mRNA expression, which coincided with TH2 cytokine mRNA expression. Immunohistological analysis demonstrated that levels of CCL17 transcripts corresponded to those of protein synthesis in the epidermis. CCL17 production was induced mainly by Langerhans cells stimulated with PEG. Furthermore, intraperitoneal injection of anti-CCL17 antibody abrogated the induction of CCR4+ cells in the skin.

CONCLUSIONS

These results suggest that PEG may induce TH2 cells in the skin through the production of CCL17 by Langerhans cells and would explain the role of colonization by S aureus in patients with atopic dermatitis.

During chronic kidney disease (CKD) leukocytes attracted by chemokines can migrate into the kidney and further aggravate renal affliction by releasing proinflammatory and profibrotic factors. We therefore sought to investigate serum and urine chemokine levels of 114 patients with CKD and 21 healthy volunteers to examine their possible suitability as biomarkers for monitoring disease course and patient's risk assessment. Analyzed chemokines were CCL17, CCL20, CCL22, and CXCL11, which are especially involved in the development of chronic renal failure. Our results showed elevated fractional CCL22 excretion levels in patients with CKD stages 2-5 compared with healthy controls. Furthermore, fractional CCL22 excretion was increased in patients with CKD stages 4 and 5 compared with stages 1-3. Fractional CCL20 excretion showed a significant elevation in patients with CKD stage 5 compared with healthy individuals and patients with CKD stages 1-3. Fractional CXCL11 excretion was significantly elevated in patients with CKD stages 4 and 5 compared with healthy controls and patients with CKD stages 1-3. Moreover, receiver operating characteristic curve analysis showed the potential of chemokine excretion to predict various CKD stages (area under the curve [AUC] 0.835, P < 0.0001 for CCL22, stage 1 and higher; AUC 0.6887, P = 0.0007 for CCL20, stage 3 and higher; AUC 0.7549, P = 0.0003 for CXCL11, stage 3 and higher). Our results further uncovered trends in varying chemokine serum and excretion levels in different CKD etiologies. In conclusion, monitoring fractional chemokine excretion might be suitable for following CKD course and hence promoting individually adjusted treatment planning.

We previously demonstrated that the most bioactive vitamin A metabolite, all-trans retinoic acid (ATRA), increased T helper 2-associated responses induced in pigs by infection with the parasitic nematode Ascaris suum We also showed that ATRA potentiated the mRNA expression of several IL-4 induced chemokines (chemokine (CC motif) ligand 11 [(CCL11), CCL17, CCL22 and CCL26] associated with alternative activation (M2a) in porcine macrophages in vitro. Herein, several mechanisms whereby ATRA affects IL-4 signaling are profiled using large-scale real time PCR and RNA-Seq analysis. Twenty-three genes associated with M2a markers in other species were independently upregulated by both IL-4 and ATRA, including the adenosine receptor A2B (ADORA2B), cysteinyl leukotriene receptor 2 (CYSLTR2) and the vitamin D receptor (VDR). ATRA synergistically enhanced IL-4 up-regulation of Hepatitis A virus cellular receptor 2 (HAVCR2) and transglutaminase 2 (TGM2) and further repressed IL-4 down-regulated CD163 and Cytochrome b-245, beta polypeptide (CYBB) mRNA. Macrophages treated with ATRA exhibited a dose-dependent reduction in phagocytosis of opsonized Staphylococcus aureus. In addition, the combination of IL-4 and ATRA up-regulated the anti-inflammatory protein, IL-1R antagonist (IL1RN) and TGM2. These data indicate that ATRA induces a state of partial alternative activation in porcine macrophages, and amplifies certain aspects of M2a activation induced by IL-4. Given the prevalence of allergic and parasitic diseases worldwide and the close similarities in the porcine and human immune responses, these findings have important implications for the nutritional regulation of allergic inflammation at mucosal surfaces.

Lung M2 macrophages are regulators of airway inflammation, associated with poor lung function in allergic asthma. Previously, we demonstrated that IL-4-induced M2 gene expression correlated with tyrosine phosphorylation of the insulin receptor substrate-2 (IRS-2) in macrophages. We hypothesized that negative regulation of IRS-2 activity after IL-4 stimulation is dependent upon serine phosphorylation of IRS-2. Herein, we describe an inverse relationship between tyrosine phosphorylation (Tyr(P)) and serine phosphorylation (Ser(P)) of IRS-2 after IL-4 stimulation. Inhibiting serine phosphatase activity increased Ser(P)-IRS-2 and decreased Tyr(P)-IRS-2 leading to reduced M2 gene expression (CD200R, CCL22, MMP12, and TGM2). We found that inhibition of p70S6K, downstream of TORC1, resulted in diminished Ser(P)-IRS-2 and prolonged Tyr(P)-IRS-2 as well. Inhibition of p70S6K increased expression of CD200R and CCL22 indicating that p70S6K negatively regulates some, but not all, human M2 genes. Knocking down GRB10, another negative regulatory protein downstream of TORC1, enhanced both Tyr(P)-IRS-2 and increased expression of all four M2 genes. Furthermore, GRB10 associated with IRS-2, NEDD4.2 (an E3-ubiquitin ligase), IL-4Rα, and γC after IL-4 stimulation. Both IL-4Rα and γC were ubiquitinated after 30 min of IL-4 treatment, suggesting that GRB10 may regulate degradation of the IL-4 receptor-signaling complex through interactions with NEDD4.2. Taken together, these data highlight two novel regulatory proteins that could be therapeutically manipulated to limit IL-4-induced IRS-2 signaling and polarization of M2 macrophages in allergic inflammation.

Immunoglobulin class switch recombination (CSR) to IgE is a tightly regulated process central to atopic disease. To profile the B-cell transcriptional responses underlying the activation of the germinal centre activities leading to the generation of IgE, naïve human B-cells were stimulated with IL-4 and anti-CD40. Gene expression and alternative splicing were profiled over 12 days using the Affymetrix Human Exon 1.0 ST Array. A total of 1,399 genes, forming 13 temporal profiles were differentially expressed. CCL22 and CCL17 were dramatically induced but followed a temporal trajectory distinct from classical mediators of isotype switching. AICDA, NFIL3, IRF4, XBP1 and BATF3 shared a profile with several genes involved in innate immunity, but with no recognised role in CSR. A transcription factor BHLHE40 was identified at the core of this profile. B-cell activation was also accompanied by variation in exon retention affecting >200 genes including CCL17. The data indicate a circadian component and central roles for the Th2 chemokines CCL22 and CCL17 in the activation of CSR.

Atopic dermatitis (AD) is a common inflammatory skin disease. Recent studies have revealed the involvement of T helper (Th)2 cytokines including Interleukin 4 (IL-4) in the pathogenesis of AD. Since epidermal Langerhans cells (LCs) and dermal myeloid dendritic cells (DCs) produce CCL17 and CCL22 that chemoattract Th2 cells, interfering with CCL17 and CCL22 production from LCs and dermal myeloid DCs may be beneficial in the treatment of AD. To investigate this, we stimulated murine bone marrow-derived DCs (BMDCs) with IL-4. IL-4 stimulation produced Ccl17 and Ccl22, which was attenuated by soybean tar Glyteer, a known aryl hydrocarbon receptor (Ahr) activator. Notably, Glyteer treatment blocked the nuclear translocation of Stat6 induced by IL-4 stimulation, suggesting that this treatment impairs the IL-4/Stat6 signaling pathway in BMDCs. Unexpectedly, Glyteer treatment did not potently upregulate the expression of Cyp1a1, a specific Ahr-responsive gene, suggesting that its inhibitory machinery for Ccl17 and Ccl22 expression is likely to operate in an Ahr-independent manner. These findings indicate that Glyteer may exhibit therapeutic potential for AD by downregulating the CCL17 and CCL22 production from DCs in a Th2-deviated microenvironment.

Regulatory T cells (Tregs) maintain immune homeostasis and modulate tumor‑induced neovascularization. However, the mechanisms underlying the role of Tregs in acute lymphoblastic leukemia (ALL) remain to be elucidated. Helios, combined with forkhead box P3, is considered a suitable marker for discriminating functional Tregs. In the present study, a microenvironment was created with a high proportion of Helios+ Tregs in T cell‑deficient nude mice to determine the mechanism underlying Tregs expressing Helios in ALL. It was revealed that umbilical cord blood‑derived Helios+ Tregs had proliferation and immunosuppression abilities similar to those of normal pediatric Tregs. The accumulation of Helios+ Tregs accelerated leukemogenesis and the infiltration of leukemic cells into the bone marrow. Importantly, a high expression of Helios in Tregs promoted angiogenesis in the bone marrow via the vascular endothelial growth factor (VEGF)A/VEGF receptor 2 (VEGFR2) pathway. Furthermore, the expression of chemokine CC‑chemokine ligand 22 (CCL22) in the bone marrow and serum of ALL mice infused with Helioshigh Treg cells was increased. The results demonstrated that Helios promotes the secretion of chemokine CCL22, which may recruit more Tregs into the bone marrow. Increased Helios+ Treg cells promoted angiogenesis in the bone marrow of ALL mice via the VEGFA/VEGFR2 pathway. Therefore, Helios may be a target to manipulate Treg activity in clinical settings.

Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is a transcription factor that mediates a broad range of cellular antioxidative, detoxification and anti-inflammatory effects. However, the precise mechanism by which Nrf2 regulates inflammation and metabolism in macrophages remains controversial and unclear. To further clarify the roles of Nrf2 in inflammation and glucose metabolism regulation, retrovirus-mediated knockdown of Nrf2 was performed in murine RAW264.7 macrophages, and the cells were stimulated with 100 ng/mL lipopolysaccharide for 24 h for M1 activation. qPCR and western blotting results indicated that Nrf2 knockdown significantly enhanced expression of the inflammatory genes Il1a and Il1b in unstimulated macrophages and increased expression of the inflammatory genes Il1a, Il1b, Il6, Il10, Ccl2, Ccl22, and CD38 but decreased that of Tnfa and Tgfb1 in M1 macrophages. Nrf2 knockdown also significantly elevated IL6 and IL10 secretion by M1 macrophages. Western blotting showed that Nrf2 knockdown reduced iNOS protein levels in resting macrophages and enhanced CD38 protein levels in both resting and M1 macrophages. The differential regulation of these macrophage inflammation and polarization markers by Nrf2 reveals multiple roles for Nrf2 in regulating inflammation in macrophages. Moreover, Nrf2 knockdown increased the Glu4 protein level and decreased AKT and GSK3β protein phosphorylation in M1 macrophages, suggesting multiple roles for Nrf2 in regulating glucose metabolism in macrophages. Overall, our results are the first to demonstrate mixed inflammation and glucose metabolism regulatory effects of Nrf2 in macrophages that may occur independent of its classic function in redox regulation. These findings support the potential of Nrf2 as a therapeutic target for the prevention and treatment of inflammation- and obesity-associated syndromes, including diabetes and atherosclerosis.