The presence of characteristic epithelial swirls called Hassall bodies within the human thymic medulla has been used as an indicator of ongoing or recent thymopoiesis. We present a case where Hassall bodies were present in the absence of current or past thymopoiesis. The patient had been treated with corticosteroids for presumed asthma before his diagnosis of X-linked SCID. Two other cases of nonimmunodeficient patients treated with high-dose corticosteroids had markedly increased numbers of thymic Hassall bodies. To determine whether corticosteroid treatment induces thymic epithelial (TE) differentiation to form Hassall bodies, mAbs reactive with specific cytokeratins (CKs), filaggrin, and involucrin were used to define distinct stages of TE cell differentiation. Treatment of primary TE monolayers with hydrocortisone in vitro induced expression of involucrin and high-molecular-mass CKs that are characteristic of TE differentiation. Treatment of thymic organ cultures with hydrocortisone induced both medullary and subcapsular cortical TE cells to express CK6, a differentiation marker that is normally expressed only by Hassall bodies in vivo. These experimental studies combined with the case observations indicate that exogenous corticosteroids can regulate terminal differentiation of TE cells both in vitro and in vivo. Thus, the presence of Hassall bodies in thymus from corticosteroid-treated patients cannot be taken as an absolute indication of previous thymopoiesis. Because corticosteroids are also made within the thymus under normal physiologic conditions, these studies support the hypothesis that endogenous corticosteroids may play a role in normal TE differentiation and Hassall body formation in vivo.

Corticosteroids (CS) are potent immunosuppressive agents that are known to affect T cell-mediated inflammation by the inhibition of proliferation and cytokine production, as well as the immunostimulatory function of monocytes and macrophages. Not much is known of the effect of corticosteroids on dendritic cells (DC), the professional T cell stimulatory antigen-presenting cells. We report that the endogenous CS hydrocortisone and the synthetic CS clobetasol-17-propionate strongly inhibited the production of the inflammatory mediators interleukin (IL)-12 p70, tumor necrosis factor alpha (TNF-alpha), and IL-6 by lipopolysaccharide (LPS)-stimulated monocyte-derived immature DC (iDC) in vitro. In contrast, the stimulatory capacity, antigen uptake, and the expression of costimulatory molecules were not affected. In accordance with the decreased production of IL-12 p70, CS-treated iDC induced less production of the inflammatory Th1 cytokine interferon-y and enhanced levels of the Th2 cytokines IL-10 and IL-5 in staphylococcal enterotoxin B-stimulated CD4+ Th cells. Furthermore, CS inhibited the maturation of iDC as assessed by the lack of expression of CD83 as well as by the prevention of the loss of antigen uptake capacities. These type 3 DC (DC3) matured in the presence of CS produce less IL-12 p70 and have a decreased T cell stimulatory capacity. Moreover, uncommitted T cells that encounter the CS-induced DC3 develop into Th2-biased cells, which may additionally decrease the Th1-mediated tissue damage but, on the other hand, Th2 cytokines may promote undesirable elevation of IgE and eosinophilia. These findings indicate that suppression of T cell-mediated inflammation by CS not only relies on direct effects on T cells, but also on various effects on DC, their professional antigen-presenting cells.

Psychologic states produced by environmental or physiologic stresses are usually associated with hypersecretion of adrenal hormones, particularly epinephrine and the glucocorticoids (hydrocortisone in humans or corticosterone in rats). A common mechanism links the secretion of these hormones, even though the adrenal medulla and cortex have different embryologic origins and biochemical properties and very different mechanisms controlling their secretory activities, ie, a cholinergic nervous input stimulates medullary secretion while a hormone, corticotropin (ACTH), activates secretion from the cortex. This mechanism is made possible by an intra-adrenal portal vascular system, which provides the medulla with uniquely high concentrations of glucocorticoids. These high concentrations are needed to induce the medullary enzyme, phenylethanolamine-N-methyltransferase (PNMT), which controls the synthesis of epinephrine from norepinephrine. By suppressing glucocorticoid secretion, pituitary failure compromises epinephrine synthesis and decreases the rate at which epinephrine is secreted; in contrast, prolonged chronic stress can enhance epinephrine synthesis and secretion within the adrenal, the brain, or both organs. This control mechanism could be involved in the long-term consequences of stress.

Supplementation of carnitine has been shown to improve performance characteristics such as protein accretion in growing pigs. The molecular mechanisms underlying this phenomenon are largely unknown. Based on recent results from DNA microchip analysis, we hypothesized that carnitine supplementation leads to a downregulation of genes of the ubiquitin proteasome system (UPS). The UPS is the most important system for protein breakdown in tissues, which in turn could be an explanation for increased protein accretion. To test this hypothesis, we fed sixteen male, four-week-old piglets either a control diet or the same diet supplemented with carnitine and determined the expression of several genes involved in the UPS in the liver and skeletal muscle. To further determine whether the effects of carnitine on the expression of genes of the UPS are mediated directly or indirectly, we also investigated the effect of carnitine on the expression of genes of the UPS in cultured C2C12 myotubes and HepG2 liver cells. In the liver of piglets fed the carnitine-supplemented diet, the relative mRNA levels of atrogin-1, E214k and Psma1 were lower than in those of the control piglets (P < 0.05). In skeletal muscle, the relative mRNA levels of atrogin-1, MuRF1, E214k, Psma1 and ubiquitin were lower in piglets fed the carnitine-supplemented diet than that in control piglets (P < 0.05). Incubating C2C12 myotubes and HepG2 liver cells with increasing concentrations of carnitine had no effect on basal and/or hydrocortisone-stimulated mRNA levels of genes of the UPS. In conclusion, this study shows that dietary carnitine decreases the transcript levels of several genes involved in the UPS in skeletal muscle and liver of piglets, whereas carnitine has no effect on the transcript levels of these genes in cultivated HepG2 liver cells and C2C12 myotubes. These data suggest that the inhibitory effect of carnitine on the expression of genes of the UPS is mediated indirectly, probably via modulating the release of inhibitors of the UPS such as IGF-1. The inhibitory effect of carnitine on the expression of genes of the UPS might explain, at least partially, the increased protein accretion in piglets supplemented with carnitine.

We initially randomly synthesized about 60 oleanane and ursane triterpenoids as potential anti-inflammatory and cancer chemopreventive agents. Preliminary screening of these derivatives for inhibition of production of nitric oxide induced by interferon-gamma in mouse macrophages revealed that 3-oxooleana-1, 12-dien-28-oic acid (B-15) showed significant activity (IC(50) = 5.6 microM). On the basis of the structure of B-15, 19 novel olean- and urs-12-ene triterpenoids with a 1-en-3-one functionality having a substituent at C-2 in ring A have been designed and synthesized. Among them, 3-oxooleana-1,12-diene derivatives with carboxyl, methoxycarbonyl, and nitrile groups at C-2 showed higher activity than the lead compound B-15. In particular, 2-carboxy-3-oxooleana-1, 12-dien-28-oic acid (3) had the highest activity (IC(50) = 0.07 microM) in this group of triterpenoids. The potency of 3 was similar to that of hydrocortisone (IC(50) = 0.01 microM), although 3 does not act through the glucocorticoid receptor. Interesting structure-activity relationships of these novel synthetic triterpenoids are also discussed.

BACKGROUND

Discoid lupus erythematosus is a chronic form of cutaneous (skin) lupus which can cause permanent scarring if treatment is inadequate. Many drugs have been used to treat this disease and some of these are potentially very toxic.

OBJECTIVE

To assess the effects of drugs for discoid lupus erythematosus.

METHODS

In June 2009 we updated our searches of the Cochrane Skin Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (Issue 2, 2009), MEDLINE, EMBASE, LILACS, and online ongoing trials registers. The reference lists of relevant reviews were searched. Index Medicus (1956 to 1966) was handsearched and we approached authors for information about unpublished trials.

METHODS

We included all randomised trials of drugs to treat people with discoid lupus erythematosus. Drugs included in the search were azathioprine, chloroquine, clofazimine, corticosteroids, (oral and topical), dapsone, gold, interferon alpha-2a, methotrexate, phenytoin, retinoids, sulphasalazine, thalidomide, topical calcineurin blockers (pimecrolimus and tacrolimus), and biological agents (etanercept, efalizimab, infliximab, and rituximab).

METHODS

Two reviewers independently examined each retrieved study for eligibility.

RESULTS

Two trials involving 136 participants were included. No new trials were included in this update.In a cross-over study of 12 weeks duration, fluocinonide 0.05% cream (a potent topical corticosteroid), appeared to be better than hydrocortisone 1% cream (a mild corticosteroid) when the first arm of the trial involving 78 participants was analysed at 6 weeks. Clearing or excellent improvement was seen in 27% of people using fluocinonide and in 10% of those using hydrocortisone, giving a 17% absolute benefit in favour of fluocinonide (95% CI 0.0 to 0.34, NNT (Number needed to treat) 6).In the second trial, acitretin (50mg/day) was compared with hydroxychloroquine (400mg/day) in 58 people in a parallel trial of 8 weeks duration. There was marked improvement or clearing in 46% of people using acitretin and in 50% of those on hydroxychloroquine but there was no significant difference between the 2 interventions. The adverse effects were more frequent and more severe in the acitretin group. In this trial clearing of erythema was measured and found to be better in the hydroxychloroquine group (RR 0.61, 95% CI 0.36 to 1.06).

CONCLUSIONS

Fluocinonide cream may be more effective than hydrocortisone in treating people with discoid lupus erythematosus. Hydroxychloroquine and acitretin appear to be of equal efficacy, although adverse effects are more frequent and more severe with acitretin. There is not enough reliable evidence about other drugs used to treat discoid lupus erythematosus.

Corticosteroid injections are the mainstay of treating tennis elbow even though their effectiveness has not been well established by controlled studies. A survey of consultant rheumatologists confirmed a widespread preference for this treatment but they varied in their choice of steroid dose and preparation. We examined the value of some practices by comparing local injections of 2 ml 1% lignocaine with either 10 mg triamcinolone or 25 mg hydrocortisone made up to 2 ml with 1% lignocaine (Study 1). The investigation was conducted double blind. Within the first 8 weeks, pain relief was greater for triamcinolone than hydrocortisone although the differences were not statistically significant. The response to both steroid preparations was significantly better than for lignocaine up to this point but at 24 weeks, the degrees of improvement were similar for all three groups and many patients still had pain. Relapse was common. In a separate but similarly designed study, triamcinolone 10 mg was compared with 20 mg of the same agent. Improvements of pain were similar and followed the same time scale. Post-injection worsening of pain occurred in approximately half of all steroid treated patients in both studies and this was sometimes severe and persistent. It was less frequent amongst those given lignocaine alone. Skin atrophy was reported in all groups but was more frequent amongst those given triamcinolone in Study 1. In conclusion, more rapid relief of symptoms was achieved with 10 mg triamcinolone than with 25 mg hydrocortisone or lignocaine alone and there was less needed to repeat injections. Results obtained with 20 mg triamcinolone were similar to those of the smaller dose.(ABSTRACT TRUNCATED AT 250 WORDS)

Individual glucocorticoid (GC) sensitivity was determined by measuring the effects of several clinically used GCs on transactivation of the GC-induced leucine zipper (GILZ) gene and on transrepression of the IL-2 gene using quantitative real-time PCR. A clear difference in relative potencies for transactivation and transrepression of the various GCs was observed, suggesting differential effects. To determine whether the in vitro outcomes could predict in vivo effects of GCs, 15 individuals underwent a 0.25-mg dexamethasone (DEX) suppression test (DST) while determining GILZ and IL-2 mRNA levels in their peripheral blood mononuclear cells incubated with hydrocortisone, DEX, budesonide, and prednisolone. No correlations were found between the DST and the two expression assays. However, significant correlations existed between hydrocortisone and DEX (r = 0.52; P = 0.046), hydrocortisone and budesonide (r = 0.48; P = 0.069), and hydrocortisone and prednisolone (r = 0.86; P = 0.007) regarding GILZ mRNA levels, and between hydrocortisone and DEX (r = 0.62; P = 0.014), hydrocortisone and budesonide (r = 0.71; P = 0.003), and hydrocortisone and prednisolone (r = 0.71; P = 0.047) regarding IL-2 mRNA levels. In conclusion, intra- and inter-individual variations in GC sensitivity were observed using two expression assays representing GC-mediated transactivation and transrepression. The two expression assays did not correlate with each other or with the results of the DST. This suggests that regulation of the hypothalamic-pituitary-adrenal axis is more complex. However, within an individual person, these two tests combined might predict what type and dosage of GC will be preferable in individual patients for its inhibitory clinical effects, together with relatively fewer transactivating effects related to adverse effects.

BACKGROUND

The aim was to survey current practice in glucocorticoid replacement therapy and self-perceived health outcomes in patients with adrenal insufficiency.

METHODS

Participants were recruited via patient organizations to respond anonymously to a web-based survey developed by clinical experts. Unique entries were set up for each patient organization enabling geographical localization of the entries.

RESULTS

1245 participants responded (primary adrenal insufficiency: 84%; secondary adrenal insufficiency: 11%; unsure: 5%). Therapies included hydrocortisone (75%), prednisone/prednisolone (11%), cortisone acetate (6%) and dexamethasone (4%). Dosing regimens were once daily (10%), twice daily (42%), thrice daily (32%) or other (17%). Compromised subjective health necessitating changes to physical activity or social-, work- or family life was reported by 64% of the participants. 40% of the participants reported absence from work/school in the last 3 months. Irrespective of diagnosis, 76% were concerned about long-term side-effects of therapy, mainly osteoporosis (78%), obesity (64%) and cardiovascular morbidity (46%). 38% of the participants had been hospitalized in the last year.

CONCLUSIONS

Glucocorticoid replacement therapy among the respondents consisted primarily of hydrocortisone administered twice or thrice daily. A majority reported impact of their disease or treatment on subjective health requiring alterations in e.g. physical activity or family life. Three quarters reported concerns about long-term side-effects of the treatment. These data demonstrate - from the patients' perspective - a need for improvement in the management of adrenal insufficiency.

Aldosterone exerts rapid "nongenomic" effects in various nonrenal tissues. Here, we investigated whether such effects occur in the human heart. Trabeculae and coronary arteries obtained from 57 heart valve donors (25 males; 32 females; 17 to 66 years of age) were mounted in organ baths. Aldosterone decreased contractility in atrial and ventricular trabeculae by maximally 34+/-3% and 15+/-4%, respectively, within 5 to 15 minutes after its application. The protein kinase C (PKC) inhibitor chelerythrine chloride, but not the mineralocorticoid receptor antagonists spironolactone and eplerenone, blocked this effect. Aldosterone also relaxed trabeculae that were prestimulated with angiotensin II (Ang II), and its negative inotropic effects were mimicked by hydrocortisone (at 10-fold lower potency) but not 17beta-estradiol. Aldosterone concentrations required to reduce inotropy were present in failing but not in normal human hearts. Previous exposure of coronary arteries to 1 micromol/L aldosterone or 17beta-estradiol (but not hydrocortisone) doubled the maximum contractile response (Emax) to Ang II. DeltaEmax correlated with extracellular signal-regulated kinase (ERK) 1/2 phosphorylation (P<0.01). Spironolactone and eplerenone did not block the potentiating effect of aldosterone. Studies in porcine renal arteries showed that potentiation also occurred at pmol/L aldosterone levels but not at 17beta-estradiol levels <1 micromol/L. Aldosterone did not potentiate the alpha1-adrenoceptor agonist phenylephrine. In conclusion, aldosterone induces a negative inotropic response in human trabeculae (thereby antagonizing the positive inotropic actions of Ang II) and potentiates the vasoconstrictor effect of Ang II in coronary arteries. These effects are specific and involve PKC and ERK 1/2, respectively. Furthermore, they occur in a nongenomic manner, and require pathological aldosterone concentrations.

<AbstractText>Sepsis is a major public health burden resulting in 25-30% in-hospital mortality and accounting for over 20 billion dollars of United States hospital costs.</AbstractText><AbstractText>This was a randomized, double-blinded, placebo controlled trial conducted from February 2018 to June 2019 assessing an ascorbic acid (AA), thiamine, and <em>hydrocortisone</em> (HAT) treatment bundle for the management of septic and septic shock patients admitted to an intensive care unit (ICU). The primary outcomes were resolution of shock and change in Sequential Organ Failure Assessment (SOFA) score. Secondary outcomes included 28-day mortality, ICU mortality, hospital mortality, procalcitonin clearance (PCT-c), hospital length of stay (LOS), ICU LOS, and ventilator free days.</AbstractText><AbstractText>137 patients were randomized to the treatment group (n = 68) and comparator group (n = 69) respectively with no significant differences in baseline characteristics. There was a statistically significant difference in the time patients required vasopressors indicating quicker reversal of shock in the HAT group compared to comparator group (27 ± 22 vs 53 ± 38 hours, p < 0.001). There was no statistically significant change in SOFA score between groups 3 (1 - 6) vs. 2 (0 - 4), p = 0.17. There were no significant differences between study arms in ICU and hospital mortality, ICU and hospital LOS, ventilator free days, and PCT-c.</AbstractText><AbstractText>Our results suggest that the combination of intravenous ascorbic acid, thiamine, and <em>hydrocortisone</em> significantly reduced the time to resolution of shock. Additional studies are needed to confirm these findings and assess any potential mortality benefit from this treatment.</AbstractText>

Clinically equivalent doses of hydrocortisone, prednisolone, and dexamethasone have progressively increasing teratogenic activity as judged by their ability to induce cleft palate in the offspring of pregnant mice treated with these drugs during the middle period of gestation. Mole for mole, dexamethasone is at least 300 times more teratogenic than hydrocortisone. The enhanced teratogenicity of dexamethasone probably does not result from its relatively decreased mineralocorticoid activity.

We have identified conditions under which late gestation fetal rat hepatocytes in primary culture proliferate in the absence of serum, polypeptide growth factors, or insulin. Fetal hepatocytes, cultured in defined minimal essential medium (MEM) with hydrocortisone, synthesized DNA within the first 6 h after plating and for up to 72 h. Rates of thymidine incorporation into DNA by fetal hepatocytes exceeded peak rates seen with adult rat hepatocytes. The latter were quiescent following isolation, with DNA synthesis only occurring after 48 h exposure to insulin plus epidermal growth factor. Although they exhibited a high rate of DNA synthesis, the fetal hepatocytes retained sensitivity to added mitogens; DNA synthesis was stimulated three- to fourfold by subnanomolar concentrations of TGF-alpha. Fetal hepatocytes also were sensitive to the growth inhibitory effects of TGF-beta at concentrations below 10 pM. Finally, ontogenic changes in serum- and mitogen-independent fetal hepatocyte growth were observed, with declining rates of DNA synthesis as term approached. We speculate that the ability of fetal rat hepatocytes to synthesize DNA independent of added serum or mitogens may coincide with a proliferative in vivo phenotype.

BACKGROUND

Conventional glucocorticoid replacement therapy fails to mimic the physiological cortisol rhythm, which may have implications for morbidity and mortality in patients with Addison's disease.

OBJECTIVE

The objective of the study was to compare the effects of continuous sc hydrocortisone infusion (CSHI) with conventional oral hydrocortisone (OHC) replacement therapy.

METHODS

This was a prospective crossover, randomized, multicenter clinical trial comparing 3 months of treatment with thrice-daily OHC vs CSHI. From Norway and Sweden, 33 patients were enrolled from registries and clinics. All patients were assessed at baseline and after 8 and 12 weeks in each treatment arm.

METHODS

The morning ACTH level was the primary outcome measure. Secondary outcome measures were effects on metabolism, health-related quality of life (HRQoL), sleep, and safety.

RESULTS

CSHI yielded normalization of morning ACTH and cortisol levels, and 24-hour salivary cortisol curves resembled the normal circadian variation. Urinary concentrations of glucocorticoid metabolites displayed a normal pattern with CSHI but were clearly altered with OHC. Several HRQoL indices in the vitality domain improved over time with CSHI. No benefit was found for either treatments for any subjective (Pittsburgh Sleep Quality Index questionnaire) or objective (actigraphy) sleep parameters.

CONCLUSIONS

CSHI safely brought ACTH and cortisol toward normal circadian levels without adversely affecting glucocorticoid metabolism in the way that OHC did. Positive effects on HRQoL were noted with CSHI, indicating that physiological glucocorticoid replacement therapy may be beneficial and that CSHI might become a treatment option for patients poorly controlled on conventional therapy.

Matrix metalloproteinases (MMPs) are endopeptidases that degrade the proteins of the extracellular matrix (ECM). Expression and activity of the MMPs are essential for embryogenesis, where MMPs participate in the normal ECM remodeling that occurs during tissue morphogenesis and development. Studies have demonstrated that MMP gene expression is inhibited by glucocorticoids in mammalian cell culture systems and that exposure to glucocorticoids causes developmental abnormalities in several species. Therefore, we proposed that glucocorticoids impede normal development through alteration of MMP expression. Zebra fish (Danio rerio) were used as a model to study MMP-13 expression both during normal embryogenesis and following acute exposure to two glucocorticoids, dexamethasone, and hydrocortisone. MMP-13 is one of three collagenases identified in vertebrates that catalyzes the degradation of type I collagens at neutral pH. MMP-13 expression varied during zebra fish development, with peak expression at 48 h post-fertilization (hpf). Morpholino knockdown studies showed that MMP-13 expression is necessary for normal zebra fish embryogenesis. Acute exposure to dexamethasone and hydrocortisone resulted in abnormal zebra fish development including craniofacial abnormalities, altered somitogenesis, blood pooling and pericardial and yolk sac edema as well as increased MMP-13 mRNA and activity at 72 hpf. In situ hybridization experiments were used to confirm the increase in MMP-13 expression following glucocorticoid treatment and showed elevated MMP-13 expression in the rostral trunk, brain, eye, heart, and anterior kidney of treated embryos. These data demonstrate that normal zebra fish embryogenesis requires MMP-13 and that dexamethasone and hydrocortisone modulate the expression of this gene, leading to increased activity and potentially contributing to subsequent dysmorphogenesis.

beta-Adrenergic agonists form high affinity complexes with receptors, resulting in activation of the associated adenylate cyclase. To examine the formation of the high affinity state of the receptor, curves were constructed for the competition of the full beta-adrenergic agonist isoproterenol, partial agonists cobefrin and soterenol, and the antagonist propranolol for [3H]dihydroalprenolol binding to beta-adrenergic receptors on human neutrophil membranes. Curve modeling by computer yielded a two-state binding model for the agonists, with distinct dissociation constants for the high (KH) and low (KL) affinity states. The ratio of dissociation constants (KL/KH) was found to be well correlated (P less than 0.01) with the drug's intrinsic activity for stimulation of adenylate cyclase. Thus, the degree of coupling of receptor occupation with adenylate cyclase activation is correlated with the magnitude of KL/KH. Administration of cortisone to humans resulted in a substantial rise in the proportion of receptors in the high affinity state and in the KL/KH determined from isoproterenol competition curves, as well as a rise in adenylate cyclase activity. Furthermore, in vitro exposure of human neutrophils to hydrocortisone resulted in a similar rise in KL/KH determined from isoproterenol competition curves. Therefore, one mechanism by which cortisone modulates beta-adrenergic receptor function appears to be through facilitating the formation of the high affinity state of the receptor, resulting in greater coupling of receptor occupation with adenylate cyclase activation.

Glucocorticoids (GCs, cortisol in human) are associated with impairments in declarative memory retrieval. Brain regions hypothesized to mediate these effects are the hippocampus and prefrontal cortex (PFC). Our aim was to use fMRI in localizing the effects of GCs during declarative memory retrieval. Therefore, we tested memory retrieval in 21 young healthy males in a randomized placebo-controlled crossover design. Participants encoded word lists containing neutral and emotional words 1 h prior to ingestion of 20 mg hydrocortisone. Memory retrieval was tested using an old/new recognition paradigm in a rapid event-related design. It was found that hydrocortisone decreased brain activity in both the hippocampus and PFC during successful retrieval of neutral words. These observations are consistent with previous animal and human studies suggesting that glucocorticoids modulate both hippocampal and prefrontal brain regions that are crucially involved in memory processing. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11682-007-9003-2) contains supplementary material, which is available to authorized users.

This study confirms the finding that washed thymocytes from rats given 100 mg of BGG 48 h earlier, when transferred to syngeneic recipients, exert a specific suppressor effect on immunological responses to BGG in the latter. The active cells are found in a subpopulation of low density, making up less than 10% of the total thymocytes, and are partially resistant to hydrocortisone.

The present results indicate that B cells isolated from chronic lymphocytic leukemia (B-CLL) from 11 of 14 patients are capable of specifically producing IgE upon costimulation with IL-4 and hydrocortisone (HC). IgE is detected by intracytoplasmic fluorescence staining and by RIA. Clinical, hematological, and immunological parameters (including Rai stage, WBC, Lc, sIg kappa/lambda, CD5, and CD23 expression) cannot distinguish the IgE responder from the nonresponder patients. IL-4 alone is a potent inducer of human IgE synthesis by normal PBMC and we show here that its effect is strikingly enhanced by HC. The IgE produced by B-CLLs are monoclonal since they display the same L chain type as the freshly isolated CD5+ B-CLLs. We, therefore, conclude that the combination of IL-4 and HC can abrogate the maturation arrest of CD5+ B-CLLs by inducing their differentiation into IgE-producing cells. The present data provide a unique model to study the isotype switching to IgE and the regulation of human IgE synthesis by monoclonal human B cells.

We have characterized precisely the cytokeratin expression pattern of sweat gland myoepithelial cells and have identified conditions for propagating this cell type and modulating its differentiation in culture. Rare, unstratified epithelioid colonies were identified in cultures initiated from several specimens of full-thickness human skin. These cells divided rapidly in medium containing serum, epidermal growth factor (EGF), and hydrocortisone, and maintained a closely packed, epithelioid morphology when co-cultured with 3T3 feeder cells. Immunocytochemical and immunoblot analysis disclosed that the cells differed from keratinocytes in that they were E-cadherin-negative, vimentin-positive, and expressed an unusual set of cytokeratins, K5, K7, K14, and K17. When subcultured without feeder cells, they converted reversibly to a spindle morphology and ceased K5 and K14 expression. Under these conditions, EGF deprivation induced flattening, growth arrest, and expression of alpha-smooth muscle actin ((&agr;)-sma). Coexpression of keratins and alpha-sma is a hallmark of myoepithelial cells, a constituent of secretory glands. Immunostaining of skin sections revealed that only sweat gland myoepithelial cells expressed the same pattern of keratins and alpha-sma and lack of E-cadherin as the cell type we had cultured. Interestingly, our immunocytochemical analysis of ndk, a skin-derived cell line of uncertain identity, suggests that this line is of myoepithelial origin. Earlier immunohistochemical studies by others had found myoepithelial cells to be K7-negative. We tested five K7-specific antibodies that can recognize this protein in western blots and in the assembled keratin filaments of mesothelial cells. Three of these antibodies did not recognize the K7 present in myoepithelial cell filaments or in HeLa cell filaments, indicating that some K7 epitopes are masked when K7 pairs with K17 instead of with its usual keratin filament partner, K19.