Associations of ErbB4 (ERBB4/HER4), the fourth member of the EGFR family, with cancer are variable, possibly as a result of structural diversity of this receptor. There are multiple structural isoforms of ERBB4 arising by alternative mRNA splicing, and a subset undergo proteolysis that releases membrane-anchored and soluble isoforms that associate with transcription factors and coregulators to modulate transcription. To compare the differential and common signaling activities of full-length (FL) and soluble intracellular isoforms of ERBB4, four JM-a isoforms (FL and soluble intracellular domain (ICD) CYT-1 and CYT-2) were expressed in isogenic MCF10A cells and their biologic activities were analyzed. Both FL and ICD CYT-2 promoted cell proliferation and invasion, and CYT-1 suppressed cell growth. Transcriptional profiling revealed several new and underexplored ERBB4-regulated transcripts, including: proteases/protease inhibitors (MMP3 and SERPINE2), the YAP/Hippo pathway (CTGF, CYR61, and SPARC), the mevalonate/cholesterol pathway (HMGCR, HMGCS1, LDLR, and DHCR7), and cytokines (IL8, CCL20, and CXCL1). Many of these transcripts were subsequently validated in a luminal breast cancer cell line that normally expresses ERBB4. Furthermore, ChIP-seq experiments identified ADAP1, APOE, SPARC, STMN1, and MXD1 as novel molecular targets of ERBB4. These findings clarify the diverse biologic activities of ERBB4 isoforms, and reveal new and divergent functions.

CONCLUSIONS

ErbB4 as a regulator of Hippo and mevalonate pathways provides new insight into milk production and anabolic processes in normal mammary epithelia and cancer.

We have previously shown that overexpression of BLyS/BAFF was associated with increased relative frequencies of innate "precursor" marginal zone (MZ)-like B-cells in the blood of HIV-1-infected rapid and classic progressors. However, along with relatively normal BLyS/BAFF expression levels, these cells remain unaltered in elite-controllers (EC), rather, percentages of more mature MZ-like B-cells are decreased in the blood of these individuals. Fluctuations in frequencies of blood MZ-like B-cell populations may reflect migratory patterns associated with disease progression status, suggesting an important role for these cells in HIV-1 pathogenesis. We have therefore longitudinally measured plasma levels of B-tropic chemokines by ELISA-based technology as well as their ligands by flow-cytometry on blood B-cell populations of HIV-1-infected individuals with different rates of disease progression and uninfected controls. Migration potential of B-cell populations from these individuals were determined by chemotaxis assays. We found important modulations of CXCL13-CXCR5, CXCL12-CXCR4/CXCR7, CCL20-CCR6 and CCL25-CCR9 chemokine-axes and increased cell migration patterns in HIV progressors. Interestingly, frequencies of CCR6 expressing cells were significantly elevated within the precursor MZ-like population, consistent with increased migration in response to CCL20. Although we found little modulation of chemokine-axes in EC, cell migration was greater than that observed for uninfected controls, especially for MZ-like B-cells. Overall the immune response against HIV-1 may involve recruitment of MZ-like B-cells to peripheral sites. Moreover, our findings suggest that "regulated" attraction of these cells in a preserved BLyS/BAFF non-inflammatory environment, such as encountered in EC could be beneficial to the battle and even control of HIV.

Appendicitis followed by appendectomy (AA) at a young age protects against inflammatory bowel disease (IBD). We wanted to characterize the role of the T helper type 17 (Th17) system involved in this protective effect. AA was performed on 5-week-old male BALB/c mice and distal-colon samples were harvested. Mice with two laparotomies each served as sham-sham (SS) controls. RNA was extracted from four individual colonic samples per group (AA and SS groups) and each sample microarray-analysed and reverse transcription-polymerase chain reaction (RT-PCR)-validated. Gene-set enrichment analysis (GSEA) showed that the Th17 recruitment factor gene CCL20 was significantly suppressed at both 3 days post-AA and 28 days post-AA. Although Th17 cell development differentiation factor genes TGF-β2 and TGF-β3 were significantly up-regulated 3 days post-AA, GSEA 28 days post-AA showed that AA down-regulated 29 gene-sets associated with TGF-β1, TGF-β2 and TGF-β3 in contrast to none up-regulated with any of these genes. GSEA showed substantial down-regulation of gene-sets associated with Th17 lymphocyte recruitment, differentiation, activation and cytokine expression in the AA group 28 days post-AA. We conclude that Th17-system cytokines are kept under control by AA via down-regulation of proinflammatory CCL20, a rapid down-regulation of pro-Th17 cell differentiation genes TGF-β2 and TGF-β3, suppression of RORC-associated gene-sets, increased protective STAT1 expression and suppression of 81 'pro-Th17' system gene-sets. AA suppresses the Th17 pathway leading to colitis amelioration. Further characterization of Th17-associated genes and biological pathways will assist in the development of better therapeutic approaches in IBD management.

Several recent studies have revealed important contributions of chemokines and their receptors to the development and progression of both hematopoietic and nonhematopoietic neoplasms. The chemokine receptor CCR6 is unusual in that it mediates leukocyte chemotaxis in response to a single chemokine, CCL20 (macrophage inhibitory factor-3alpha), as well as in response to a family of antimicrobial peptides termed "beta-defensins." CCR6 is critical for mucosal immunity, and expression of the receptor is tightly regulated on hematopoietic cells. Here we characterize the expression of CCR6 on B cells and B-cell non-Hodgkin's lymphomas. We demonstrate that CCR6 expression is limited to cells comprising the mantle and marginal zones of the secondary lymphoid tissues and serves to identify the majority of mantle cell, marginal zone, and mucosa-associated lymphoid tissue lymphomas. Furthermore, we show that CCR6 serves as a functional chemokine receptor when expressed by neoplastic cells. Finally, we establish that the cognate ligand for CCR6 is present on mucosal epithelium infiltrated by neoplastic cells in select extranodal lymphomas. Thus, CCR6 is a useful new marker identifying a subset of B-cell non-Hodgkin's lymphomas and likely contributes to the localization of select extranodal lymphomas at mucosal sites.

Chemokines and their receptors play important roles in various aspects of tumoral processes, and evidence was provided for their critical involvement in determining the metastatic destination of tumor cells. Here, we analyzed in vitro and in vivo, how CCR6 expression could alter the behavior of Lewis lung carcinoma (LLC) cells, which were shown to express low levels of the CCR6 ligand, CCL20 (LARC), both in vitro and in vivo. The expression of CCR6 significantly decreased the number of metastases in immunocompetent C57BL/6 mice, without affecting the tumor-forming ability of LLC cells. This was correlated with a decrease in clonogenicity in soft and hard agar, and with increased adhesion to type-IV collagen. These two observations made in basal conditions were enhanced when CCL20 was added to the assay medium. Thus, expression of CCR6 in tumor cells, associated with the local production of CCL20, decreased the metastatic potential of the LLC line. We propose a model, in which the expression of a chemokine receptor in tumor cells can act as a metastasis-suppressor, or a metastasis-promoting factor, according to the expression, or the absence of expression of the cognate ligand(s) in the tumor.

BACKGROUND

Chlamydophila pneumoniae may contribute to the pathogenesis of asthmatic airway inflammation through chemical mediators secreted by C. pneumoniae-infected bronchial epithelial cells (BECs). Recently, CCL20 and vascular endothelial growth factor (VEGF) were reported to be released from BECs and to play a role in the pathogenesis of asthma.

OBJECTIVE

To determine if C. pneumoniae infection of BECs induces the secretion of CCL20 and VEGF, we measured that by ELISA in human BECs infected with C. pneumoniae. Transcripts of CCL20 and VEGF were assayed by semi-quantitative RT-PCR. To investigate the underlying mechanism, the activation of MAPK and intracellular reactive oxygen species (ROS) in these C. pneumoniae-infected BECs was measured, as well as the effects of inhibitors of MAPK and ROS on CCL20 and VEGF expression.

RESULTS

Compared with non-infected BECs, C. pneumoniae-infected BECs showed enhanced secretion of CCL20 and VEGF. C. pneumoniae-infected BECs also showed enhanced intracellular ROS and an increased ratio of phosphorylated to non-phosphorylated p38. Inhibition of p38 suppressed CCL20 and VEGF secretion, as did a NADPH oxidase blocker and an antioxidant, in C. pneumoniae-infected BECs.

CONCLUSIONS

C. pneumoniae infection of BECs may play a role in the pathogenesis of asthma through the enhanced production of CCL20 and VEGF. The association between increased cytokine production and increased intracellular ROS suggests that antioxidants may benefit asthmatics in selected situations.

Monocyte-derived dendritic cell functions have been explored for identification of contact allergens in vitro. Current methods, including measurement of changes in cell surface marker expression (e.g. CD83, CD86) do not provide a sensitive method for detecting the sensitising potential of a chemical. In this study, we investigated whether chemokine production by monocyte-derived dendritic cells is increased upon maturation and whether chemokine production can provide methodology for the detection of allergens. Monocyte-derived dendritic cells were exposed to allergens (nickel sulphate, cobalt chloride, palladium chloride, copper sulphate, chrome-(III)-chloride, potassium dichromate, p-phenylenediamine and dinitrochlorobenzene) and irritants (sodium dodecyl sulphate, dimethylsulphoxide, benzalkoniumchloride and propane-1-ol). CD83 and CD86 expression was analysed by flow cytometry and chemokine production (CXCL8, CCL5, CCL17, CCL18, CCL19, CCL20, CCL22) was determined by ELISA. Significant up regulation of CD83 and CD86 expression could only be induced by three out of seven and five out of seven allergens, respectively. In contrast, CXCL8 production was significantly increased after stimulation with all allergens tested, whereas irritant exposure led to decreased CXCL8 production. All other chemokines tested, failed in identifying contact allergens. In conclusion, CXCL8 production, next to CD83 and CD86 up regulation, by monocyte-derived dendritic cells provides a promising in vitro tool for discrimination between allergens and irritants.

DNA vaccination is a promising method to induce specific immune responses. However, it remains challenging to enhance DNA vaccine potency. Chemokines were used as adjuvants to improve the efficacy of DNA vaccination. Herein, we fused murine chemokine CCL20 or CXCL13 to a model antigen green fluorescent protein (GFP). The fusion DNA vaccines enhanced specific anti-GFP immune responses in mice compared with vector pEGFP-N1. Co-immunization with both of chemokine-GFP fusion constructs induced the significantly highest level of humoral immune responses. CCL20-GFP or CXCL13-GFP fusion DNA vaccine induced predominant IgG2a or IgG1 response respectively. However, co-immunization with both of these fusion DNA vaccines induced a predominant IgG2a response. Therefore, fusing chemokine CXCL13 or CCL20 to antigen provides new attractive strategy to enhance the immunogenicity of DNA vaccine and modulate immune responses.

OBJECTIVE

To clarify the composition of wound fluid (WF) and investigate the impact of WF on breast cancer cell lines.

METHODS

The proliferation and migration of WF-treated breast cancer cells MDA-MB-231 and MCF-7 were assessed with colony formation test, MTT cell proliferation test and scratch wound test. The quantitative profiles of WF were analyzed using Bio-Plex Pro kits.

RESULTS

The proliferation and migration of WF-treated breast cancer cells were significantly higher than that of untreated cells. Fifteen cytokines, 29 chemokines and 9 matrix metalloproteinases (MMPs) were assessed in WF. The concentrations of these factors were influenced by post-surgery days, neoadjuvant chemotherapy (NAC), TNM stage, pathological type and molecular subtype. The WF harvested from patients underwent NAC showed significant higher profiles of interleukin-1β (IL-1β), IL-4, IL-6, IL-17F, IL-21, IL-23, IL-25, IL-31, Interferon γ (IFNγ), CD40 ligand (CD40L), tumor necrosis factor α (TNFα), CXCL1, CXCL2, CXCL5, CCL3, CCL7 and CCL20.

CONCLUSIONS

Surgery-induced WF promotes the proliferation and migration of breast cancer cells. The composition of WF is influenced by various clinical features and provides potential therapeutic targets to control local recurrence and tumor progression.

Invasive aspergillosis caused by Aspergillus species (Aspergillus fumigatus, A. flavus, and A. terreus) is life-threatening infections in immunocompromised patients. Understanding the innate and adaptive immune response particularly T-helper cells (TH-cells) against these Aspergillus species and how the different sub-set of TH-cells are regulated by differentiating cytokines at primary target organ site like lung, kidney and brain is of great significance to human health. This review focuses on presentation of Aspergillus through Antigen presenting cells (APCs) to the naive CD4(+) T-cells in the host. The production of differentiating/effector cytokines that activate following TH-cells, e.g., TH1, TH2, TH9, and TH17 has been reported in association or alone in allergic or invasive aspergillosis. Chemokines (CXCL1, CXCL2, CCL1, and CCL20) and their receptors associated to these TH-cells have also been observed in invasive aspergillosis. Thus, further study of these TH-cells in invasive aspergillosis and other elements of adaptive immune response with Aspergillus species are required in order to have a better understanding of host response for safer and effective therapeutic outcome.

OBJECTIVE

Previous studies have revealed that interleukin 17 (IL-17) contributes to pathological processes in many solid tumors. However, the roles of IL-17 in gynecologic cancer still remain elusive, hindering the deep understanding of gynecologic tumorigenesis.

METHODS

In the present study, to delineate the functional roles of IL-17 in gynecologic cancer, IL-17 stimulation was introduced in cell lines of 3 gynecologic cancers, and IL-17-induced expression of chemokines and cytokines and possible signaling pathways were investigated.

RESULTS

Our results showed that in HEC-1-B (human endometrial cancer) cells, IL-17 stimulation induced mRNA level increases of CCL2, CCL5, CCL20, CXCL2, and IL-8. Similar treatment in HeLa cells caused increases in the mRNA levels of CCL2, CXCL2, IL-6, and IL-8, and in SKOV3 cells, mRNA levels of CCL2, CCL20, CXCL1, CXCL2, IL-6, and IL-8 increased. The increases in mRNA levels induced by IL-17 were dose- and time-dependent. Furthermore, with the addition of the NF-κB (nuclear factor κ-light-chain-enhancer of activated B) and extracellular signal-regulated kinase inhibitors pyrrolidine dithiocarbamate and PD98059, the IL-17-induced CCL2 mRNA level was significantly compromised. IL-17 stimulation also activated phosphorylation of IκBα and extracellular signal-regulated kinase 1/2 in a time-dependent manner.

CONCLUSIONS

These results demonstrated that IL-17 may regulate chemokines and cytokines in gynecologic cancers.

Ganoderma lucidum is a medicinal mushroom in China and other Asian countries. The polysaccharide from G. lucidum (PS-G) is a branched (1-->6)-beta-d-glucan moiety. In this study, we examined the effects of PS-G on human monocyte-derived dendritic cells (DCs) with microarray analysis by Human Genome U133 Plus 2.0 GeneChip. In comparing mean signal values between PS-G-treated DCs with untreated DCs, 3477 (17%) probe sets were up-regulated, and 4418 (19%) probe sets were down-regulated after PS-G treatment. These results demonstrate that genes associated with phagocytosis (CD36, CD206, and CD209) are decreased and genes associated with proinflammatory chemokines (CCL20, CCL5, and CCL19), cytokines [interleukin (IL)-27, IL-23A, IL-12A, and IL-12B], and costimulatory molecules (CD40, CD54, CD80, and CD86) are increased. To confirm the microarray data, we further investigated the effect of PS-G on antigen-specific antibody and cytokine production in BALB/c mice. Immunization with ovalbumin (OVA)/PS-G showed that the anti-OVA IgG2a levels were significantly increased compared with OVA alone in BALB/c mice. Together, our data demonstrate that PS-G could effectively promote the activation and maturation of immature DCs, preferring a T helper 1 response. Furthermore, the results also demonstrate that the data from microarray analysis could be correlated with the in vivo effect of the immune-enhancing compound.

ATP is released by human periodontal ligament cells (hPDLCs) and has been shown to regulate PDL regeneration and responses to mechanical stress through activation of P2Y receptors. This nucleotide, however, has also been reported to trigger the pro-inflammatory cascade by inducing the maturation and/or release of chemokines/cytokines from various cell types mainly via P2X7 receptors. Much less is known on the possible role of ATP in stem cells deriving from PDL (hPDLSCs) which are considered to be a promising tool for cell-based therapy to restore lesions. Given the role played by P2X7 in pathophysiological conditions, in this study we investigated the expression of P2X7 ATP receptors in hPDLSCs. The results obtained showed that hPDLSCs express P2X7 receptors evaluated by means of cytofluorimetric, immunohistochemistry, reverse transcriptase-PCR, and Western blot analyses. P2X7 ligation by 2',3'-(benzoyl-4-benzoyl)-ATP (BzATP), a specific receptor agonist, was followed by an increase in intracellular Ca2+ and in the uptake of ethidium bromide. These effects were dramatically reduced by oxidized ATP (oATP), the P2X7 irreversible inhibitor, suggesting that the P2X7 is the functional receptor involved. At 24 h treatment of hPDLSCs with BzATP it enhanced the release of the pro-inflammatory agents IL8 and CCL20, without influencing cell viability. These effects were counteracted by pre-treating the cells with oATP or with A-740003, a selective and potent P2X7 competitive antagonist. Collectively, these results indicated that extracellular ATP mediate a pro-inflammatory response via P2X7 receptors in hPDLSCs opening a further approach to control hPDLSCs behavior in their possible application as therapeutic tool.

Oncostatin M (OM) transforms the lymph node (LN) into a "super lymphoid organ" with 2 striking features: massive thymus-independent T-cell development and major expansion of the memory T-cell pool. We report that T-cell development in the LckOM LN is regulated by a cyclooxygenase-2 (COX-2)-dependent neoangiogenesis involving high endothelial venules (HEVs). That LN HEVs are particularlyrich in OM-receptor beta-chain provides aplausible explanation for the fact that extrathymic T-cell development in LckOM mice is limited to the LN. Moreover, we found that increased production of the CCL20 chemokine by LN stromal cells was instrumental in the expansion of the memory phenotype CD4 T-cell pool in LckOM mice. The generality of the latter finding was demonstrated by the fact that CCL20/CCR6 interactions increase the basal proliferation rate of CD62L(lo) CD4 T cells irrespective of their thymic (in non-OM-transgenic mice) or extrathymic (in LckOM mice) origin. To our knowledge, CCL20 is the first molecule found to increase the proliferation of memory phenotype CD4 T cells. These findings identify potential targets for the creation of thymic substitutes (LN HEVs) and for expansion of the CD4 memory T-cell compartment (CCL20).

Th17-mediated neutrophilic airway inflammation has been implicated in decreased response to glucocorticoids in asthma. We aimed to investigate the effect of glucocorticoids on the airway epithelial release of the neutrophilic and Th17-cell chemoattractant CCL20. We studied CCL20 and CXCL8 sputum levels in asthmatic subjects using inhaled glucocorticoids or not, and the effect of budesonide on CCL20 and CXCL8 production in primary bronchial epithelial cells. The mechanism behind the effect of budesonide-induced CCL20 production was studied in 16HBE14o- cells using inhibitors for the glucocorticoid receptor, intracellular pathways and metalloproteases. We observed higher levels of CCL20, but not CXCL8, in the sputum of asthmatics who used inhaled glucocorticoids. CCL20 levels correlated with inhaled glucocorticoid dose and sputum neutrophils. Budesonide increased tumour necrosis factor (TNF)-α-induced CCL20 by primary bronchial epithelium, while CXCL8 was suppressed. In 16HBE14o- cells, similar effects were observed at the CCL20 protein and mRNA levels, indicating transcriptional regulation. Although TNF-α-induced CCL20 release was dependent on the ERK, p38 and STAT3 pathways, the increase by budesonide was not. Inhibition of glucocorticoid receptor or ADAM17 abrogated the budesonide-induced increase in CCL20 levels. We show that glucocorticoids enhance CCL20 production by bronchial epithelium, which may constitute a novel mechanism in Th17-mediated glucocorticoid-insensitive inflammation in asthma.

BACKGROUND

Pulpitis is characterized by the marked infiltration of inflammatory cells in response to an invasion of caries-related bacteria. It is well known that chemokines regulate the trafficking of lymphocytes, and CC chemokine ligand 20 (CCL20) has been recently shown to play a crucial role in the recruitment of memory T cells and immature dendritic cells into inflammatory lesions. We previously reported that CCL20 was mainly expressed in microvascular endothelial cells and macrophages that accumulated in inflamed pulp tissues and that its specific receptor, CCR6, was expressed on infiltrated lymphocytes. However, the mechanism of CCL20 expression remains unclear.

RESULTS

In this study, we investigated the expression of CCL20 in monocytes/macrophages, endothelial cells, and pulpal fibroblasts after stimulation with Streptococcus mutans, a representative of caries-related bacteria, or proinflammatory cytokines. CCL20 messenger RNA was detected by reverse transcription-polymerase chain reaction in inflamed pulp, but not in clinically normal pulp. By enzyme-linked immunosorbent assay, S. mutans induced a human monocytic cell line, differentiated macrophage-like THP-1 cells, and human umbilical vein endothelial cells (HUVEC) to produce an increased amount of CCL20. Lipoteichoic acid from S. mutans also elicited CCL20 production by HUVEC. Moreover, CCL20 production from pulpal fibroblasts was increased by stimulation with inetrleukin-1beta and tumor necrosis factor-alpha.

CONCLUSIONS

Our results indicate that CCL20 expression is induced by stimulation with caries-related bacteria that have invaded deeply into the dentinal tubules as well as by proinflammatory cytokines in the inflamed pulpal lesions. It may be involved in the progression of pulpitis via accumulation of inflammatory cells.

Chemokines may contribute to the systemic inflammation that is linked to the increased risk of co-morbidities in patients with psoriasis. The aim of this study was to investigate circulating chemokines in patients with psoriasis and their relationship to disease severity. Analysis of plasma levels of chemokines in patients with psoriasis before narrowband ultraviolet B (UVB) therapy revealed increased expression of Th1-associated CXCL9 and -10, Th2-associated CCL17 and CCL22, and Th17-associated CCL20. CCL20 correlated with disease severity. UVB therapy reduced skin symptoms, but did not affect the chemokine levels in plasma. Anti-CD3 and anti-CD28-mediated activation of peripheral blood mononuclear cells (PBMCs) caused a higher secretion of Th2 cytokine interleukin (IL)-13 by PBMCs from patients with psoriasis than from healthy controls. The sustained high expression of inflammatory chemokines is a potential link to systemic inflammation in psoriasis. UVB therapy may be a more effective treatment of local rather than systemic inflammation.

The mucosal gene expression in rectosigmoid mucosa (RSM) in irritable bowel syndrome with diarrhea (IBS-D) is unknown. Our objectives were, first, to study mRNA expression [by RT(2) PCR of 19 genes pertaining to tight junctions, immune activation, intestinal ion transport and bile acid (BA) homeostasis] in RSM in IBS-D patients (n = 47) and healthy controls (n = 17) and study expression of a selected protein (PDZD3) in 10 IBS-D patients and 4 healthy controls; second, to assess RSM mRNA expression according to genotype and fecal BA excretion (high ≥ 2,337 μmol/48 h); and third, to determine whether genotype or mucosal mRNA expression is associated with colonic transit or BA parameters. Fold changes were corrected for false detection rate for 19 genes studied (P < 0.00263). In RSM in IBS-D patients compared with controls, mRNA expression of GUC2AB, PDZD3, and PR2Y4 was increased, whereas CLDN1 and FN1 were decreased. One immune-related gene was upregulated (C4BP4) and one downregulated (CCL20). There was increased expression of a selected ion transport protein (PDZD3) on immunohistochemistry and Western blot in IBS-D compared with controls (P = 0.02). There were no significant differences in mucosal mRNA in 20 IBS-D patients with high compared with 27 IBS-D patients with normal BA excretion. GPBAR1 (P < 0.05) was associated with colonic transit. We concluded that mucosal ion transport mRNA (for several genes and PDZD3 protein) is upregulated and barrier protein mRNA downregulated in IBS-D compared with healthy controls, independent of genotype. There are no differences in gene expression in IBS-D with high compared with normal fecal BA excretion.

The COVID-19 pandemic caused by the SARS-CoV-2 virus, overlaps with the ongoing epidemics of cigarette smoking and electronic cigarette (e-cig) vaping. However, there is scarce data relating COVID-19 risks and outcome with cigarette or e-cig use. In this study, we mined three independent RNA expression datasets from smokers and vapers to understand the potential relationship between vaping/smoking and the dysregulation of key genes and pathways related to COVID-19. We found that smoking, but not vaping, upregulates ACE2, the cellular receptor that SARS-CoV-2 requires for infection. Both smoking and use of nicotine and flavor-containing e-cigs led to upregulation of pro-inflammatory cytokines and inflammasome-related genes. Specifically, chemokines including CCL20 and CXCL8 are upregulated in smokers, and CCL5 and CCR1 are upregulated in flavor/nicotine-containing e-cig users. We also found genes implicated in inflammasomes, such as CXCL1, CXCL2, NOD2, and ASC, to be upregulated in smokers and these e-cig users. Vaping flavor and nicotine-less e-cigs, however, did not lead to significant cytokine dysregulation and inflammasome activation. Release of inflammasome products, such as IL-1B, and cytokine storms are hallmarks of COVID-19 infection, especially in severe cases. Therefore, our findings demonstrated that smoking or vaping may critically exacerbate COVID-19-related inflammation or increase susceptibility to COVID-19.

Keywords: ACE2; COVID-19; SARS-CoV-2; cytokines; electronic cigarettes; immune response; inflammation; tobacco; vaping.

The CC chemokine receptor 6 (CCR6) and its ligand CCL20 are involved in human colorectal cancer (CRC) carcinogenesis and can promote the progression of CRC. In addition, interleukin-17 (IL-17), produced by a T cell subset named "Th17," has been identified as an important player in inflammatory responses, and has emerged as a mediator in inflammation-associated cancer. However, the relevance of IL-17 in the development and progression of CRC still remains to be explored. This study aimed to investigate the effect of IL-17 on the cell migration of CRC cells. Human CRC HCT-116 cells were used to study the effect of IL-17 on CCR6 expression and cell migration in CRC cells. IL-17 treatment induced migration of HCT-116 cells across the Boyden chamber membrane and increased the expression level of the CCR6. Inhibition of CCR6 by small interfering RNA (siRNA) and neutralizing antibody inhibited IL-17-induced cell migration. By using specific inhibitors and short hairpin RNA (shRNA), we demonstrated that the activation of ERK and p38 pathways are critical for IL-17-induced CCR6 expression and cell migration. Promoter activity and transcription factor ELISA assays showed that IL-17 increased NF-κB-DNA binding activity in HCT-116 cells. Inhibition of NF-κB activation by specific inhibitors and siRNA blocked the IL-17-induced CCR6 expression. Our findings support the hypothesis that CCR6 up-regulation stimulated by IL-17 may play an active role in CRC cell migration.

BACKGROUND

Crohn's disease (CD) and ulcerative colitis (UC) are inflammatory bowel diseases (IBDs) presumably caused by dysregulated immune responses to the gut microbiota. Genetic association studies have implicated dozens of chromosomal regions or loci in IBD susceptibility. The next challenge is to explain the individual role of each of these modest effect loci in the disease state. We have previously identified MAST3 as an IBD susceptibility gene through genetic fine-mapping of the 19p linkage region. Testing MAST3 in a reporter assay provided preliminary evidence that MAST3 modulates the activity of inflammation-related transcription factor nuclear factor kappa B.

METHODS

Here we characterized the function of MAST3 through an examination of the influence of the modulation of MAST3 expression on endogenous genome-wide expression patterns. More specifically, we looked at differential gene expression resulting from overexpression and knockdown of the MAST3 gene in epithelial and macrophage cell lines. From we highlight a group of genes whose expression is modulated by MAST3 and correlate their expression with NF-jB activity. Their expression was found to be enriched in inflamed mucosal tissue of UC patients, confirming the importance of these genes in IBD.

RESULTS

We highlight a group of genes whose expression is modulated by MAST3 and correlate their expression with NF-κB activity. Their expression was found to be enriched in inflamed mucosal tissue of UC patients, confirming the importance of these genes in IBD. These MAST3-regulated genes are central to mucosal immune responses. Among them are proinflammatory cytokines (e.g., CCL20, IL8), regulators of NF-κB (e.g., TNFAIP3, LY96, NFKBIA), genes involved in interferon-induced defense against pathogen invasion (e.g., IFIT1, ISG15), and genes involved in cell adhesion and/or migration (e.g., CD44, TMOD1).

CONCLUSIONS

Taken together, these results confirm MAST3 as a modulator of the inflammatory response through regulation of immune gene expression in the gut of IBD patients.

In line with SARS and MERS, the SARS-CoV-2/COVID-19 pandemic is one of the largest challenges in medicine and health care worldwide. SARS-CoV-2 infection/COVID-19 provides numerous therapeutic targets, each of them promising, but not leading to the success of therapy to date. Neither an antiviral nor an immunomodulatory therapy in patients with SARS-CoV-2 infection/COVID-19 or pre-exposure prophylaxis against SARS-CoV-2 has proved to be effective. In this review, we try to close the gap and point out the likely relationships among lysosomotropism, increasing lysosomal pH, SARS-CoV-2 infection, and disease process, and we deduce an approach for the treatment and prophylaxis of COVID-19, and cytokine release syndrome (CRS)/cytokine storm triggered by bacteria or viruses. Lysosomotropic compounds affect prominent inflammatory messengers (e.g., IL-1B, CCL4, CCL20, and IL-6), cathepsin-L-dependent viral entry of host cells, and products of lysosomal enzymes that promote endothelial stress response in systemic inflammation. As supported by recent clinical data, patients who have already taken lysosomotropic drugs for other pre-existing conditions likely benefit from this treatment in the COVID-19 pandemic. The early administration of a combination of antivirals such as remdesivir and lysosomotropic drugs, such as the antibiotics teicoplanin or dalbavancin, seems to be able to prevent SARS-CoV-2 infection and transition to COVID-19.

Keywords: COVID-19; SARS-CoV-2; approved active compounds; cathepsin L; cytokine release syndrome; cytokine storm; lysosome; lysosomotropic compounds; lysosomotropism; viral host cell entry.

T-helper cells producing interleukin (IL)-17A and IL-17F cytokines (Th17 cells) are considered the source of autoimmunity in rheumatoid arthritis (RA). In this study, we characterized specific pathogenic features of Th17 cells in RA. By using nano-string technology, we analyzed transcription of 419 genes in the peripheral blood CCR6(+)CXCR3(-) CD4(+) cells of 14 RA patients and 6 healthy controls and identified 109 genes discriminating Th17 cells of RA patients from the controls. Th17 cells of RA patients had an aggressive pathogenic profile and in addition to signature cytokines IL-17, IL-23 and IL-21, and transcriptional regulators RAR-related orphan receptor gamma of T cells (RORγt) and Janus kinase 2 (JAK2), they produced high levels of IL-23R, C-C chemokine ligand type 20 (CCL20), granulocyte-monocyte colony-stimulating factor (GM-CSF ) and transcription factor Tbet required for synovial homing. We showed that Th17 cells are enriched with Helios-producing Foxp3- and IL2RA-deficient cells, indicating altered regulatory profile. The follicular T-helper (Tfh) cells presented a functional profile of adaptor molecules, transcriptional regulator Bcl-6 and B-cell activating cytokines IL-21, IL-31 and leukemia inhibitory factor (LIF ). We observed that anti-tumor necrosis factor (TNF) treatment had a limited effect on the transcription signature of Th17 cells. Patients in remission retained the machinery of receptors (IL-23R and IL-1R1), proinflammatory cytokines (IL-17F, IL-23, IL-21 and TNF ) and adaptor molecules (C-X-C chemokine receptor 5 [CXCR5] and cytotoxic T-lymphocyte-associated protein 4 [CTLA-4]), essential for efficient transdifferentiation and accumulation of Th17 cells. This study convincingly shows that the peripheral blood CCR6(+)CXCR3(-) CD4(+) cells of RA patients harbor pathogenic subsets of Th17 and Tfh cells, which may transdifferentiate from Tregs and contribute to perpetuation of the disease.

Rhesus monkey rhadinovirus (RRV) is a gamma-2 herpesvirus related to the human Kaposi's sarcoma-associated herpesvirus (KSHV or human herpesvirus 8). This study identified an alternatively spliced gene at the right side of the RRV genome (strain 17577) between open reading frame 75 and the terminal repeat region. Of its eight exons, the first seven encoded up to 12 transmembrane domains, whilst the eighth exon encoded a predicted C-terminal cytoplasmic domain. Structurally and positionally, this RRV gene therefore resembles the K15 gene of KSHV; it was provisionally named RK15 to avoid confusion with other RRV17577 genes. In ectopic expression studies, the 55 kDa RK15 protein isoform activated the JNK and NF-kappaB pathways, like the 45 kDa KSHV K15-encoded protein isoform. In contrast to K15, which activates angiogenic and inflammatory cytokines such as interleukin (IL)-8, IL-6 and CCL20, the range of cellular transcripts activated by the RRV K15 homologue was much more restricted, but included IL-6, IL-8 and FGF21. These data suggest functional differences between terminal membrane proteins at the right end of the genomes of Old World primate gamma-2 herpesviruses.