CD34+ cells in the peripheral blood transport herpes simplex virus DNA fragments to the skin of patients with erythema multiforme (HAEM)

Herpes simplex virus (HSV)-associated erythema multiforme (HAEM) is a recurrent disease characterized by the presence and expression of HSV DNA fragments in lesional skin. Our studies examined the mechanism of viral DNA transport to the skin of HAEM patients. CD34+ cells were isolated from the blood of normal subjects and HSV and HAEM patients during acute lesions and at quiescence. They were cultured with cytokines that favor their differentiation into Langerhans cells (LC) precursors (CD1a+/CD14-) and examined for HSV replication, HSV-induced cellular alterations, viral DNA fragmentation, and clearance. CD34+ cells from all study groups were non-permissive for HSV replication but infection favored their differentiation into CD1a+/CD14- LC precursors and upregulated E-cadherin expression, thereby assisting LC targeting to the skin. Only HAEM patients had CD34+ cells that retained viral DNA fragments, notably polymerase DNA, for at least 7 d of in vitro culture. The percentages of circulating CD34+ (and CD34+/CLA+) cells were significantly higher in HAEM patients at the time of acute lesions. A similar increase was not seen for HSV patients. The data are the first report implicating CD34+ cells in HAEM pathogenesis, likely by transporting HSV DNA fragments to lesional skin.     

Erythema multiforme lesions are associated with expression of a herpes simplex virus (HSV) gene and qualitative alterations in the HSV-specific T-cell response

A common form of erythema multiforme, herpes-associated erythema multiforme (HAEM), occurs following infection with herpes simplex virus (HSV). Here we report that HSV gene expression and the qualitative nature of the virus-specific T-cell responses are related to HAEM lesion development. Skin from HAEM lesions and 1–3 months healed HAEM lesional skin were positive for the viral DNA polymerase gene (Pol) by polymerase chain reaction. However, gene expression as determined by immunohistochemistry with Pol-specific antibody was seen only in HAEM lesions, suggesting that lesion development is associated with Pol gene expression. Similar HSV-specific T-cell lymphoproliferative responses were seen in peripheral blood mononuclear cells (PBMCs) from patients with acute or healed HAEM lesions or HSV lesions and from HSV-seropositive patients with unrelated inflammatory diseases. However, the T-cell receptor variable (Vβ ) chain repertoire of HSV-stimulated PBMCs obtained from HAEM lesions was altered; the prevalence of some families of variable chain (namely Vβ16 and Vβ19) was reduced, whereas the prevalence of others was increased (namely Vβ2 and Vβ7). Vβ2 cells were found in HAEM lesional skin positive for Pol antigen, suggesting that these cells home to viral antigen-positive skin.     

Examination of non-involved skin, previously involved skin, and peripheral blood for herpes simplex virus DNA in patients with recurrent herpes-associated erythema multiforme

The association between infection with HSV and the subsequent, development of erythema multiforme is well established, although the role that the virus plays in the pathogenesis of this disorder is not known. HSV DNA has been detected in cutaneous lesions of herpes-associated erythema multiforme (HAEM), and it has been suggested that the tissue damage seen in these lesions is virus-specific. In the current, prospective study, we examined biopsies of lesional, non-involved, and previously involved but healed skin, in addition lo specimens of peripheral blood, from patients with HAEM, for HSV DNA by using the polymerase chain reaction. HSV DNA was detected in lesional skin of 10 of 11 patients compared to 2 of 11 non-involved skin biopsies obtained at the same time. I ISV was present in 4 of 6 blood specimens obtained during the acute episode. Five patients returned 3 months after the acute episode resolved for biopsies of previously involved skin. HSV was detected in 4 of these 5 biopsies. Thus, the presence of HSV DNA in the skin of pal inns with HAEM appears lo be predominantly in areas of clinical involvement; the virus remains in those cutaneous sites for up to 3 months without evidence of clinical disease; and HSV DNA may be detected in the peripheral blood cells during acute HAEM. Based on these findings, we suggest that the virus plays a role in lesion development, that the skin may function as a site of viral persistence, and that hemalogenous spread of viral DNA may bean important factor in the development of HAEM.     

Longitudinal study of a patient with herpes-simplex-virus-associated erythema multiforme: viral gene expression and T cell repertoire usage.

BACKGROUND: Erythema multiforme is a polymorphous self-limited, often recurrent eruption that can follow herpes simplex virus (HSV) infection, hereby designated HAEM. Studies of relatively large groups of patients during one recurrent episode indicated that HAEM pathogenesis is associated with HSV gene expression, Vbeta2 T cell infiltration of lesional skin and altered T cell receptor (TCR) repertoire usage by HSV-stimulated peripheral blood mononuclear cells (PBMC). However, HAEM recurrences are not always preceded by overt HSV eruptions and virus cannot be isolated from HAEM lesional skin. Therefore, it is unknown whether all HAEM recurrences experienced by a given patient are HSV related. OBJECTIVE: The studies described in this report were designed to examine whether all HAEM recurrences experienced by a given patient are HSV related. METHODS: We describe one patient who was studied longitudinally during 6 HAEM recurrences and in the intervening lesion-free periods. Lesional skin from all HAEM episodes was studied for HSV gene expression and infiltration by Vbeta2 and Vbeta3 T cells. PBMC obtained at these times were assayed for TCR repertoire usage upon HSV stimulation. RESULTS: Lesional skin from all HAEM episodes was positive for HSV gene expression (RNA and protein) as well as Vbeta2 T cell infiltration. HSV-stimulated PBMC obtained at these times had an altered TCR repertoire characterized by a predominance of Vbeta2 cells. The duration of viral gene expression, Vbeta2 cell infiltration and altered TCR repertoire usage correlated with the duration of clinical symptoms. CONCLUSION: The data suggest that HSV and a virus-specific immunopathology component are involved in the causation of all HAEM episodes experienced by the patient.     

Detection of herpes simplex virus DNA in cutaneous lesions of erythema multiforme

The association between erythema multiforme (EM) and herpes simplex virus (HSV) infection has long been appreciated, although the exact role which HSV may play in the pathogenesis of this herpes-associated EM (HAEM), is unknown. Previous studies have suggested, but not definitively demonstrated, the presence of HSV in lesions of HAEM. The presence of HSV would support the hypothesis that an immune-mediated response directed against HSV-specific antigens in the skin is central to lesion development in HAEM. The purpose of this study was to examine lesions of EM for the presence of HSV DNA by using the polymerase chain reaction (PCR). In addition, in situ hybridization using an HSV-specific RNA probe was performed to further localize the HSV nucleic acids within the skin. DNA was extracted from formalin-fixed, paraffin-embedded specimens of cutaneous lesions of HAEM and also from EM for which no precipitating factor could be documented, otherwise known as idiopathic EM (IPEM). DNA from lesions of bullous pemphigoid served as a negative control. Using PCR to specifically amplify HSV sequences which might be present, and then performing Southern analysis, we demonstrated HSV DNA in 9/13 HAEM and 6/9 IPEM biopsies. No HSV was detected in six lesions of bullous pemphigoid. In situ hybridization of three cutaneous HAEM lesions using an 35S-labeled HSV-specific RNA probe localized the HSV nucleic acids predominantly to the epidermis. Three biopsies of chronic dermatitis, used as negative controls, did not demonstrate this specific hybridization. These findings confirm the presence of HSV in lesions of HAEM and are consistent with the concept of an HSV-specific immune-mediated pathogenesis for this disease. In addition, most cases of IPEM appear to be herpes associated despite the absence of clinically apparent HSV infection.     

Detection of herpes simplex virus genomic DNA in various subsets of Erythema multiforme by polymerase chain reaction

BACKGROUND: The wide variation in the detection of herpes simplex virus (HSV) DNA (36-75%) by polymerase chain reaction (PCR) in erythema multiforme (EM) may be partly attributed to differences in case selection in terms of subsets of EM studied. OBJECTIVE: To determine the frequencies of detection of HSV DNA in specific subsets of EM. METHODS: Nested PCR was used to detect HSV DNA in skin biopsies with histologically proven EM. RESULTS: PCR was performed on skin biopsies from 63 patients with EM. HSV DNA was detected in 3/11 (27.2%) of single-episode HSV-associated EM (HAEM), 6/10 (60%) of recurrent HAEM, 1/4 (25%) of single-episode idiopathic EM and 6/12 (50%) of recurrent idiopathic EM. HSV DNA was not detected in atypical EM (0/11), suspected drug-induced EM (0/9) or Stevens-Johnson syndrome (0/6). CONCLUSION: The overall PCR positive rates of HAEM (42.9%) and idiopathic EM (43.8%) were comparable suggesting that idiopathic EM is likely to be related to a subclinical HSV infection.     

寻常型银屑病与单纯疱疹病毒1型相关性的研究

目的 探讨寻常型银屑病与单纯疱疹病毒1型(HSV-1)的可能相关性。方法 应用PCR法检测患者皮损、外周血单一核细胞(PBMCs)和咽拭子中HSV-1DNA,ELISA法检测患者血清中抗HSV-1的IgM、IgG抗体,并与正常人对照做比较。结果 患者皮损、PBMCs和咽拭子中HSV-1DNA检出率分别为37.5%、18.6%和18.8%,血清中抗HSV-1的IgM、IgG抗体检出率分别为37.2%和53.5%.经χ²检验,患者皮损、PBMCs中HSV-1DNA和血清中IgM抗体检出率显着高于正常人对照,点滴状患者的皮损、PBMCs和咽拭子中HSV-1DNA以及血清中抗HSV-1IgM抗体检出率显着高于斑块状患者。结论 寻常型银屑病尤其是皮损呈点滴状者与HSV-1显着相关,患者可能存在HSV-1的近期感染。     

Herpes simplex virus antigens and inflammatory cells in oral lesions in recurrent erythema multiforme. Immunoperoxidase and autoradiographic studies

Herpes simplex virus (HSV) antigens were sought in 15 biopsy specimens from both lesional mucosa and clinically healthy looking oral mucosa between attacks in patients with erythema multiforme (EM). Four of the eight biopsy specimens obtained from lesional EM mucosa stained positively with HSV-1-and/or HSV-2-specific antisera applied in direct immunoperoxidase staining. Of the 16 tissue specimens used as controls, two displayed positive staining with HSV-1 and/or HSV-2. Five of the seven biopsy specimens from macroscopically healthy oral mucosa obtained between attacks from patients with recurrent EM stained positively with HSV-1 and/or HSV-2. Of the six tissue specimens used as controls, three stained positively. Most of the local inflammatory mononuclear cells belonged to the T cell series, mainly to the CD-4 subset. A small proportion of the local T cells were blast transformed as assessed by CD-25 expression and [3H]thymidine incorporation. This, together with the findings showing a lower degree of activation in the biopsy from macroscopically healthy looking mucosa between attacks suggest an active role of the cell-mediated immune response in the genesis of oral lesions in EM. The persistence of HSV antigens, and the well-established role of HSV as a precipitating factor in recurrent EM, suggest that HSV may be involved, but since HSV seems to be present in other mucosal lesions as well as in clinically healthy mucosa, quite frequently an additional, hitherto unknown factor must be present in order that EM may occur.     

Epstein-Barr virus-related persistent erythema multiforme in chronic fatigue syndrome.

BACKGROUND--Erythema multiforme (EM) has been rarely reported in Epstein-Barr virus (EBV)-associated diseases; this includes patients with chronic fatigue syndrome who have chronic or recurrent and disabling illness and an abnormal antibody reactivity to EBV. We describe a patient fulfilling the chronic fatigue syndrome diagnostic criteria who had developed an unusually persistent EM resistant to corticosteroids therapy. The EBV DNA was studied in skin EM lesions, throat washings, peripheral mononuclear cells, and plasma. The EBV antigens were studied in skin EM lesions and in mononuclear cells. The patient was followed up to 2 years. OBSERVATIONS--The patient had abnormal titers of antibodies against various EBV antigens and by immunofluorescence she disclosed the EBV nuclear antigen and the viral capsid antigen in the blood vessels of the affected skin. The dot blot hybridization assay detected viral DNA in throat washings and mononuclear cells, but not in plasma. The presence of the viral genomic content in lesional skin is suggested by the autoradiographic signal and by the difference from appropriate control specimens. Skin lesions and constitutional symptoms cleared after acyclovir sodium therapy and recurred after discontinuation of this therapy. CONCLUSIONS--This is the first EM case in which evidence of the EBV causal role has been provided. The association with chronic fatigue syndrome suggests the EBV role in selected cases of this syndrome.     

The herpes-specific immune response of individuals with herpes-associated erythema multiforme compared with that of individuals with recurrent herpes labialis

Infection with herpes simplex virus (HSV) is the most common precipitating factor in the development of erythema multiforme (EM). It is not known why only a few of the many individuals who experience recurrent HSV infection also develop herpes-associated EM (HAEM), although a difference in the HSV-specific immune response has been postulated. The purpose of this study was to compare the HSV-specific immune response of individuals with HSV infection alone with that of individuals with HAEM. There were 21 patients in each of the two groups. Four parameters of the HSV-specific immune response were examined: (1) anti-HSV IgG titers were measured by ELISA; (2) antibody neutralization was assessed using a plaque assay; and (3) antibody-dependent complement-mediated cytotoxicity, and (4) antibody-dependent cellular cytotoxicity were investigated using a previously described in vitro HSV-specific cytotoxicity assay. No statistically significant differences were detected between the two patient groups. Thus, a difference in these HSV-specific immune mechanisms does not explain the development of HAEM in some individuals with recurrent HSV infection.Grant support: AI 16637 from the National Institutes of Allergy and Infectious Disease     

Expression of cytokines and chemokine receptors in the cutaneous lesions of erythema multiforme and Stevens-Johnson syndrome/toxic epidermal necrolysis

BACKGROUND: Erythema multiforme (EM) and Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) are caused by a dysregulation of cellular immunity. OBJECTIVES: To evaluate further the potential role of certain cytokines and chemokine receptors in cutaneous lesions of patients affected by EM and SJS/TEN and to establish whether such diseases are polarized preferentially towards a T-helper (Th) 1 or Th2 pattern. METHODS: Biopsy specimens from eight patients with EM, six with SJS/TEN and three healthy controls were stained for immunohistochemical examination using the alkaline phosphatase-antialkaline phosphatase method. The monoclonal antibodies used included those to tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin (IL)-2, IL-5, IL-13, receptor 3 for C-C chemokines (CCR3), receptor 3 for C-x-C chemokines (CXCR3) and CXCR4. RESULTS: The SJS/TEN specimens showed significantly higher expression of all the cytokines and chemokine receptors (except CXCR3) tested than the EM specimens. Both lesional series showed significantly higher expression of all the receptors tested than the healthy control specimens, with the sole exception of a lower expression of CCR3 in EM specimens. Comparison between molecules associated with a Th1 or Th2 response revealed a predominance of Th1 response in EM and no significant imbalance between Th1 and Th2 in SJS/TEN. CONCLUSIONS: We have provided further evidence that TNF-alpha is strongly expressed in SJS/TEN lesions and therefore it may be involved in the epidermal necrosis featured in such diseases. IFN-gamma may play an important role both in EM and SJS/TEN. IL-2, IL-5 and IL-13 may contribute to the cutaneous immunoinflammation in these diseases. Chemokine receptors may be involved strongly in the recruitment of inflammatory cells in lesional skin. In our cases we found a sharp polarization towards a Th1 pattern in EM, while the SJS/TEN lesions showed a mixed Th1/Th2 pattern.     

Erythema multiforme: Differences between HSV‐1 and HSV‐2 and management of the disease—A case report and mini review

Erythema multiforme (EM) is an immune‐mediated reaction characterized by target lesions and with possible mucosal involvement. Its most frequent cause is HSV, with HSV‐1 more common than ?2. It is usually self‐limited but it can show recurrences. We report a peculiar case of recurrent herpes‐associated erythema multiforme (HAEM) in a 35‐year‐old man. The patient was affected by both herpes labialis and genitalis, but the typical target lesions were only associated with recurrent herpes labialis. Here, we hypothesize about the pathogenic differences between HSV‐1 and HSV‐2, and discuss the therapeutic management of HAEM.     

TGF-beta1-mediated regulation of thymus and activation-regulated chemokine (TARC/CCL17) synthesis and secretion by HaCaT cells co-stimulated with TNF-alpha and IFN-gamma

Thymus and activation-regulated chemokine (TARC/CCL17) contributes not only to the recruitment of leukocytes, but is also involved in immune disorders, such as atopic dermatitis (AD) and bronchial asthma. We have previously reported that the levels of TARC were high in patients with AD and that lesional epidermis were strongly immunoreactive for TARC. In this paper, the effects of transforming growth factor (TGF)-beta(1) on the expression of TARC/CCL17 were examined in HaCaT cells, a human keratinocytes (KCs) cell line, co-stimulated with TNF-alpha and IFN-gamma. We found that TGF-beta(1) down-regulated the TARC synthesis and secretion of HaCaT cells co-stimulated with TNF-alpha and IFN-gamma in a dose-dependent manner. TGF-beta(1) at a concentration of 10ng/ml maximally inhibited this secretion. Northern blot analysis showed a similar inhibitory effect of TGF-beta(1) on TARC mRNA expression by HaCaT cells. The TGF-beta(1)-induced down-regulation of TARC/CCL17 in HaCaT cells suggests that TGF-beta(1) might regulate the TARC-related inflammatory processes, which may be important for understanding the pathogenesis of allergic diseases.     

Investigation of herpes simplex virus DNA in pityriasis rosea by polymerase chain reaction

BACKGROUND: Pityriasis rosea (PR) is an acute, inflammatory disease of unknown cause. Clinical and experimental findings indicate an infectious etiology of PR. Our purpose is to examine the skin lesions and blood samples of PR patients by polymerase chain reaction (PCR) for the presence of HSV type 1 and 2 DNA. METHODS: The lesional skin biopsies from 10 patients and blood samples from two randomized patients with clinically and histologically confirmed pityriasis rosea were examined by PCR. RESULTS: No HSV 1 and HSV 2 DNA was detected in the lesional biopsy and blood samples. CONCLUSIONS: We could not identify a relationship between HSV 1, HSV 2 and PR.     

Interferon (IFN)-gamma is a main mediator of keratinocyte (HaCaT) apoptosis and contributes to autocrine IFN-gamma and tumour necrosis factor-alpha production

BACKGROUND: Apoptosis of keratinocytes or intestinal epithelial cells is an important pathophysiological mechanism of organ damage during acute graft-versus-host disease. OBJECTIVES: To analyse in detail the mediators and their mutual interaction leading to keratinocyte apoptosis. METHODS: Experiments were performed using a keratinocyte cell line (HaCaT) and human skin explant cultures. RESULTS: Supernatants (SN) of major histocompatibility complex nonmatched mixed lymphocyte cultures (MLCs) induced apoptosis in HaCaT cells and also in keratinocytes from skin biopsies. Although both interferon (IFN)-gamma and Fas ligand (FasL) were detected in MLC-SN by enzyme-linked immunosorbent assay, the apoptosis-inducing capacity could be fully abrogated by neutralization of IFN-gamma, but not by neutralization of FasL. Recombinant (r) IFN-gamma induced HaCaT keratinocyte apoptosis in a dose- and time-dependent manner. Induction of HaCaT apoptosis by rFasL alone was induced only at higher doses than present in MLC-SN, but apoptosis was dramatically enhanced in the presence of rIFN-gamma. Further synergistic effects with IFN-gamma in the induction of apoptosis were also observed with agonistic antitumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) receptor 2 antibody, soluble TRAIL and TNF-alpha. However, in contrast to FasL and TRAIL, TNF-alpha alone did not induce HaCaT apoptosis. Interleukin-1beta and lipopolysaccharide did not enhance the apoptosis-inducing effect of IFN-gamma. Beside its apoptosis-inducing capacity in HaCaT cells, rIFN-gamma also induced autocrine IFN-gamma production, and combined treatment with IFN-gamma and TNF-alpha induced autocrine TNF-alpha production. Neutralization of autocrine IFN-gamma protected HaCaT cells from apoptosis. CONCLUSIONS: Taken together, our data suggest a central role for IFN-gamma in HaCaT keratinocyte apoptosis but also show the importance of co-acting mediators such as TNF-alpha, TRAIL and FasL, which potentiate the effect of paracrine and autocrine IFN-gamma and TNF-alpha release.     

Development of an in vitro keratinocyte model for use in the study of HSV specific cytotoxicity

Herpes simplex virus (HSV) specific immune mediated cytotoxicity may be involved in control of HSV infections and in the tissue damage induced by HSV infection or HSV related skin disease such as herpes associated erythema multiforme. Developing an in vitro model to study this process has proved difficult due to the lack of an appropriate target cell that will express HSV antigens but is not simultaneously subject to viral induced cell death. The purpose of this study was to develop a model in which keratinocytes express cell surface HSV specific antigens but at the same time are protected from death due to viral infection. We found that keratinocytes infected with HSV in the presence of acyclovir (ACV) expressed such antigens yet remained viable for a period of time after the onset of antigen expression such that cytotoxicity studies could be successfully performed. Rabbit skin cells, a transformed keratinocyte line, or second passage human neonatal foreskin keratinocytes were grown in culture medium with or without 200 microM ACV and were infected with HSV. Examination by direct immunofluorescence with anti-HSV antibody revealed uniform HSV antigen expression by cells both with and without ACV by 8 h after infection. Cells infected without ACV exhibited marked structural abnormalities including formation of multinucleated giant cells, while cells with ACV showed fewer such changes throughout a 24-h period. An Ethidium Bromide-Acridine Orange cytotoxicity assay demonstrated significant increases in the cytotoxicity of infected cells not protected by ACV compared to that of cells with ACV (p less than .001). This in vitro model should prove useful in the investigation of HSV specific immune mediated cytotoxicity.     

Antitumour necrosis factor-alpha chimeric antibody (infliximab) inhibits activation of skin-homing CD4+ and CD8+ T lymphocytes and impairs dendritic cell function

BACKGROUND: Psoriasis is a chronic inflammatory skin disease characterized by hyperproliferation and altered differentiation of keratinocytes in reply to cytokines such as interferon (IFN)-gamma and tumour necrosis factor (TNF)-alpha, provided by infiltrating CD4+ and CD8+ T cells and natural killer cells. Infliximab is a chimeric monoclonal antibody that neutralizes both soluble and membrane-bound TNF-alpha, and that may give a long-term disease remission. OBJECTIVES: To determine the in vitro effects of infliximab on CD4+ and CD8+ T cells derived from lesional skin, and on dendritic cells (DCs). METHODS: Psoriatic T-cell lines were isolated from lesional skin of four patients with psoriasis and assayed for their proliferation, cytokine release and susceptibility to apoptotic stimuli in the presence of graded (1-100 microg mL(-1)) concentrations of infliximab. DCs were differentiated in the presence of infliximab from peripheral blood monocytes. Phenotype was assessed by fluorescence-activated cell sorting and antigen-presenting capacity in functional assays. RESULTS: In vitro activation of psoriatic as well as antigen (nickel)-specific skin-homing T cells was strongly and dose-dependently impaired by infliximab, in terms both of proliferation and of IFN-gamma release. Despite the significant reduction of IFN-gamma secretion, infliximab only marginally affected the release of interleukin (IL)-10 by skin T cells, thus determining a reduction of the IFN-gamma/IL-10 ratio at the site of inflammation. The effects were maximal when T-cell activation occurred in the absence of costimulation, or when T cells were activated by immature compared with mature DCs. In addition, skin-homing CD8+ T cells were more prominently affected by infliximab compared with CD4+ T lymphocytes, both in terms of inhibition of activation and in their susceptibility to apoptosis. Finally, infliximab directly affected the differentiation of monocyte-derived DCs, by inhibiting the expression of CD1a and CD86, and strongly impaired the antigen-presenting capacity of immature and, to a lesser extent, mature DCs. CONCLUSIONS: Infliximab directly affects psoriatic T cells and impairs the antigen-presenting capacity of DCs. These effects may help to explain the long-term disease remission obtained with the drug.     

Candida albicans-specific lymphoproliferative and cytokine (IL-4 and IFN-gamma) responses in atopic eczema dermatitis syndrome. Evidence of CD4/CD8 and CD3/CD16+CD56 ratio elevations in vitro

BACKGROUND: Hypersensitivity to cross-reactive mannan polysaccharide allergens of saprophytic yeasts is likely to be involved in the pathogenesis of atopic eczema dermatitis syndrome (AEDS). Mannans induce elevated specific immunoglobulin E and lymphoproliferative responses in peripheral blood mononuclear cells (PBMCs). To gain more detailed data of the involvement of different subpopulations of PBMCs in AEDS after mannan stimulation, changes in the cell-surface marker distribution were analysed. METHODS: The Ficoll-isolated PBMCs of eight yeast hypersensitive AEDS patients and seven non-AEDS controls were stimulated in vitro by mannan (CAM) or whole extract antigen [In-House Reference (IHR)] of Candida albicans or tuberculin [purified protein derivative (PPD)] and after immunofluorescence staining analysed by flow cytometry. The expression of cytokine mRNA was measured by kinetic real-time polymerase chain reaction (TaqMan). RESULTS: After 7-day antigen stimulation, there were significant increases in the CD3/CD16(+)CD56 ratio (P = 0.028 with mannan and P = 0.006 with IHR), CD4/CD8 ratio (P = 0.049 with mannan) and interleukin-4/interferon-gamma (IL-4/IFN-gamma) mRNA ratio (P = 0.028 with IHR) and a decrease in the CD3/CD19 ratio (P = 0.035 with mannan) of AEDS patients' PBMCs as compared with healthy controls' cells. These changes were not seen in cultures with PPD. CONCLUSIONS: The observed CAM and IHR-induced elevations in T cell/natural killer cell, CD4/CD8 and IL-4/IFN-gamma ratios suggest that C. albicans-induced TH(2)-type responses can also play a role in AEDS.     

IL-13-stimulated human keratinocytes preferentially attract CD4+CCR4+ T cells: possible role in atopic dermatitis

Skin inflammation in atopic dermatitis (AD) is characterized by the predominant infiltration of T-helper (Th)2-cells in lesional skin. However, the mechanism of recruitment of these cells in lesional skin of AD is not yet fully elucidated. In this study, we investigated the role of IL-13-stimulated human primary keratinocytes (HPKs) in the recruitment of lymphocytes and further delineated the mechanism of enrichment of these cells. In the migration assays, we observed preferential enrichment of CD4(+)CCR4(+) T cells towards IL-13-stimulated HPKs. Interestingly, CD4(+)CCR4(+) T cells from AD showed a higher chemotactic response than those from healthy individuals. We observed a significant increase in the expression of CCL22 in IL-13-stimulated HPKs as compared to unstimulated cells. Blocking of CCL22 in IL-13-stimulated HPKs by a neutralizing antibody resulted in 70-90% inhibition in migration of CD4(+)CCR4(+) T cells. Moreover, IL-13 upregulated IFN-gamma-induced chemokines, CCL2 and CCL5, in HPKs. Taken together, our data suggest that IL-13-stimulated HPKs participate in a positive feedback loop by preferentially enriching Th2-cells in lesional skin of acute AD patients. However, in chronic phase, IL-13 may act in synergy with IFN-gamma resulting in lymphocytes recruitment of a mixed phenotype at the site of inflammation, thus contributing to the chronification of eczema.