Cytokine profile of patients with bullous pemphigoid

Increased risk of stroke in patients with bullous pemphigoid: a population-based follow-up study

BACKGROUND AND PURPOSE

Although previous research reveals that cardiovascular events and thromboembolic diseases are important causes of death in patients with bullous pemphigoid (BP), the risk of stroke after the diagnosis of BP relative to the general population remains unknown. Using a randomly selected nationwide population-based sample, this study investigates the risk of stroke in patients with BP compared with unaffected individuals of a similar age.

METHODS

This study analyzes data from Taiwan's National Health Insurance Research Database. This sample included 390 patients with BP and 1950 matched subjects as a comparison group. Stratified Cox proportional hazard regressions were used to calculate the 3-year stroke risk for these 2 groups after adjusting for patient's age, sex, and comorbid medical disorders at baseline.

RESULTS

Of the 2340 patients in the sample, 312 patients (13.3%) had strokes during the 3-year follow-up period, 89 (22.8% of the patients with BP) in the study group and 223 (11.4% of patients without BP) in the comparison group (P<0.001). The hazard ratio for stroke for patients with BP was 2.37 (95% CI, 1.78 to 3.15; P<0.001) times as high that for patients without BP within the 3-year follow-up period after adjusting for hypertension, diabetes, hyperlipidemia, heart failure, atrial fibrillation, and coronary heart disease.

CONCLUSIONS

Patients with BP have an increased risk of stroke and particularly ischemic stroke.

Serum chemokine profile in patients with bullous pemphigoid

BACKGROUND

Bullous pemphigoid (BP) is an autoimmune inflammatory disease causing blister formation at the dermoepidermal junction. Cutaneous infiltration of activated CD4+ T cells and eosinophils is an early event in blister formation during the disease process, suggesting that the trafficking of circulating leucocytes through the sites of inflammation is crucial in the pathogenesis of the disease. While the accumulated evidence suggests that some cytokines are involved in the pathogenesis, there have been few reports about serum chemokine profiles in patients with BP.

OBJECTIVES

To determine serum profiles of various chemokines and their clinical association in patients with BP.

METHODS

Concentrations of 10 chemokines - interferon (IFN)-gamma-inducible protein-10 (IP-10), monokine induced by IFN-gamma (MIG), macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, RANTES, eotaxin, monocyte chemoattractant protein (MCP)-1, MCP-2, MCP-3 and growth-regulated oncogene-alpha- were measured in serum samples from 38 patients with BP, 16 with pemphigus vulgaris (PV) and 17 normal controls using a sandwich immunoassay-based multiplex protein array system.

RESULTS

While there was no significant increase in any serum chemokine levels in patients with PV, serum levels of IP-10 and MCP-1 were significantly increased in patients with BP compared with healthy controls. Furthermore, serum levels of IP-10, MIG, MCP-1 and eotaxin in patients with BP increased significantly with disease severity as determined by the area affected.

CONCLUSIONS

These observations suggest that an elaborately orchestrated network of chemokines, especially MCP-1 and IP-10, contributes to the pathomechanism of BP.

High level of thymus and activation-regulated chemokine in blister fluid and sera of patients with bullous pemphigoid

BACKGROUND

Bullous pemphigoid (BP) is an autoimmune blistering disease characterized by eosinophilia and high serum IgE levels. The accumulated evidence suggests that various cytokines are involved in the lesional skin of patients with BP. Recently, thymus and activation-regulated chemokine (TARC/CCL17), a CC chemokine, was identified as a selective chemoattractant for CC chemokine receptor 4 (CCR4)-expressing cells.

OBJECTIVE

In this study, we examined the involvement of TARC in patients with BP.

METHODS

We determined the fluid and serum TARC levels in patients with BP by enzyme-linked immunosorbent assay and compared the serum TARC levels with the eosinophil numbers in peripheral blood. We also compared the serum TARC levels in five patients with BP before and after they were treated. Moreover, we examined TARC, CCR4 and CXC chemokine receptor 3 (CXCR3) expression in the lesional skin of patients with BP by immunohistochemical procedures. Furthermore, we measured CCR4 positivity in CD4+ CD45RO+ cells of peripheral blood mononuclear cells (PBMCs) in patients with BP and healthy control subjects.

RESULTS

The fluid TARC levels in patients with BP were significantly higher than those in blisters from burn patients or suction blisters of healthy control subjects. The serum TARC levels in patients with BP were also significantly higher than those in pemphigus vulgaris (PV) patients and healthy control subjects, and decreased after the treatment. The serum TARC levels in patients with BP significantly correlated with the eosinophil numbers in peripheral blood (r = 0.72, P < 0.002). Immunohistochemistry showed a strong reactivity of TARC in the epidermal keratinocytes (KCs) of BP. Moreover, both CCR4 and CXCR3 were expressed on the dermal infiltrating CD4+ T cells mainly beneath the bullae of patients with BP. Fluorescence-activated cell sorting analysis showed a higher percentage of CCR4 positivity in CD4+ CD45RO+ cells of PBMCs in patients with BP than that in healthy control subjects, while there was no significant difference of CXCR3 positivity in CD4+ CD45RO+ cells of PBMCs between patients with BP and healthy control subjects.

CONCLUSIONS

These findings strongly suggest that TARC may be one of the important chemokines that are involved in the pathogenesis of BP.

IL-4, IL-5, TGF-beta1 and IFN-gamma mRNAs detected by a new in situ amplification system in cicatricial pemphigoid

The process that induces chronic progressive scarring in cicatricial pemphigoid (CP), a rare group of autoimmune mucocutaneous blistering diseases, is still under investigation. The tendency to heal with scar formation observed in CP could be due to the specific localization of the antigen in the basement membrane zone or could depend on the frequent recurrence of the disease in a localized area. The release of soluble fibrogenic factors by inflammatory infiltrating cells has also been considered as pathogenetically relevant. The aim of this study is to evaluate the expression of mRNA for IL-4, IL-5, TGF-beta1, IFN-gamma in patients with CP, and investigate the role of the cytokine profile as a possible cause of the clinical features and course of the disease. Fourteen patients (3 male, 11 female; age range 40-72 years) with oral (n = 10), preputial (n = 3) and cutaneous (n = 1) CP were studied. The formalin-fixed and paraffin-embedded biopsies were examined by in situ hybridization performing a new amplification system based on biotinyl-tyramide. As a control, 4 patients (2 male, 2 female; age range 58-73 years) affected by bullous pemphigoid (BP), the most common autoimmune subepidermal blistering disease, were also examined. In CP, IL-4 mRNA expression was present in 4 out of the 14 cases analysed. IL-5 was detected in 12 CP biopsies. TGF-beta1 and IFN-gamma mRNAs were identified in 9 and 11 CP cases, respectively. In BP, an IL-4 hybridization signal could not be observed in any of the cases. By contrast IL-5, TGF-beta1 and IFN-gamma mRNA analyses were positive in all four BP cases. Our results suggest the presence of a T-cell population with a mixed cytokine pattern in the cellular infiltrate of both blistering diseases, with a corresponding increase of Th2-like activity in fully developed lesions, irrespective of the different sites involved. In addition, on the basis of the constant presence of TGF-beta1 mRNA in the different lesional phases of CP, and its overlapping expression in BP, we hypothesize that the involvement of additional factors is responsible for the scarring course typical of CP.

Mast cells play a key role in neutrophil recruitment in experimental bullous pemphigoid

Bullous pemphigoid (BP) is an inflammatory subepidermal blistering disease associated with an IgG autoimmune response to the hemidesmosomal protein BP180. Passive transfer of antibodies to the murine BP180 (mBP180) ectodomain triggers a blistering skin disease in mice that depends on complement activation and neutrophil infiltration and closely mimics human BP. In the present study, we show that mast cells (MCs) play a crucial role in experimental BP. Wild-type mice injected intradermally with pathogenic anti-mBP180 IgG exhibited extensive MC degranulation in skin, which preceded neutrophil infiltration and subsequent subepidermal blistering. In contrast, mice genetically deficient in MCs or MC-sufficient mice pretreated with an inhibitor of MC degranulation failed to develop BP. Further, MC-deficient mice reconstituted in skin with MCs became susceptible to experimental BP. Despite the activation of complement to yield C3a and C5a, in the absence of MCs, accumulation of neutrophils at the injection site was blunted. The lack of response due to MC deficiency was overcome by intradermal administration of a neutrophil chemoattractant, IL-8, or by reconstitution of the injection sites with neutrophils. These findings provide the first direct evidence to our knowledge that MCs play an essential role in neutrophil recruitment during subepidermal blister formation in experimental BP.

High levels of interleukin-8, soluble CD4 and soluble CD8 in bullous pemphigoid blister fluid. The relationship between local cytokine production and lesional T-cell activities

BACKGROUND

Bullous pemphigoid (BP) is an inflammatory subepidermal blistering disease associated with autoantibodies that recognize hemidesmosomal proteins. In addition to autoantibodies, the cell-mediated immune reaction is considered to play an important part in blister formation. Objectives To investigate some T-cell activation markers and inflammatory cytokines in the blister fluid and sera of patients with BP.

METHODS

We measured soluble CD4 (sCD4) and soluble CD8 (sCD8), which have been, respectively, associated with CD4 and CD8 T-cell activation. Enzyme-linked immunosorbent assays were also used to quantify the production of the leucocyte chemoattractant interleukin (IL) -8 and of the cytokines IL-1alpha, IL-1beta, IL-6, IL-10 and tumour necrosis factor-alpha in the blister fluid and sera of 11 patients with BP.

RESULTS

The mean +/- SD level of sCD4 in patients' blisters (42.4 +/- 25.0 units mL-1) was significantly elevated (P < 0.005) compared with that in their sera (11.2 +/- 8.9) and that in the suction blisters of 10 healthy people (11.4 +/- 5.4; P < 0.005). Mean +/- SD IL-8 concentrations in BP blisters (4683.6 +/- 3878.1 pg mL-1) were much higher than those in their sera (17.1 +/- 18.9; P < 0.001), and were very significantly elevated (P < 0.005) in comparison with those in suction blisters of healthy persons (512 +/- 292). sCD4 levels in BP blisters were inversely related to IL-10 levels (P = 0. 03, r2 = 0.85), IL-8 levels were positively related to sCD8 levels (P = 0.01, r2 = 0.54), and IL-1beta levels were positively related to sCD8 concentrations (P < 0.005, r2 = 0.65).

CONCLUSIONS

The correlations suggest that there is a delicately orchestrated network of cytokines and cell-mediated immunity operating in BP blisters.

Acquired skin disease of hemidesmosomes

The hemidesmosome is a membrane-associated supramolecular dermal epidermal complex linking the cytoskeleton of the basal keratinocyte to structures within the papillary dermis. Different components of this complex have been identified as autoantigens in autoimmune bullous skin diseases. Some of the autoantigens have been characterized at the molecular level. Little is known, however, about the factors that initiate the production of autoantibodies. By histopathology, acquired skin diseases of hemidesmosomes show subepidermal blisters and by direct immunofluorescence, linear deposits of IgG, C3 or IgA at the dermal epidermal junction. Bullous pemphigoid (BP) is the most common acquired disease of hemidesmosomes. Two proteins, BP180 and BP230, have been identified as primary targets of autoantibodies in BP. In addition, pemphigoid/herpes gestationis, lichen planus pemphigoides, cicatricial pemphigoid and linear IgA disease are characterized by an immune response to BP180. Laminin 5 is another well-characterized anchoring filament-lamina densa component of hemidesmosomes. Patients with autoantibodies to laminin 5 show the clinical phenotype of cicatricial pemphigoid. Other acquired skin diseases of the hemidesmosomes reveal autoantibodies to a plectin-like protein, the beta4 subunit of alpha6beta4 integrin, uncein and a not yet characterized 168 kDa protein. Recently, diseases with autoantibodies to 105 and 200 kDa proteins of the lower lamina lucida have been reported. The association of these autoantigens with hemidesmosomes still needs to be demonstrated. Finally, anchoring fibrils associate with the dermal epidermal anchoring complex. The major structural component of anchoring fibrils is type VII collagen, the autoantigen of epidermolysis bullosa acquisita.

Polymorphic eruption of pregnancy and herpes gestationis: comparison of granulated cell proteins in tissue and serum

Polymorphic eruption of pregnancy (PEP) and herpes gestationis (HG) are pregnancy-related dermatoses of unknown aetiology with eosinophil infiltration which, at early stages, may show similar clinical and histopathological features. To determine the relative contributions of eosinophils, neutrophils and mast cells to the pathogenesis of PEP and HG through deposition of granule proteins, we studied tissue and serum from 15 patients with PEP and 10 with HG. Using indirect immunofluorescence with antibodies to human eosinophil granule major basic protein (MBP), eosinophil-derived neurotoxin (EDN), eosinophil cationic protein (ECP), neutrophil elastase and mast cell tryptase, we determined and compared cellular and extracellular staining patterns in lesional skin biopsy specimens and, using immunoassay, measured MBP, EDN, and ECP in patients' sera. Eosinophil infiltration and extracellular protein deposition of all three eosinophil granule proteins were present in both PEP and HG indicating a pathogenic role for eosinophils in both diseases. Staining for eosinophil granule proteins was especially prominent in urticarial lesions and around blisters in HG. EDN and ECP serum levels in PEP and ECP serum levels in HG were significantly increased compared with those in normal pregnant and normal nonpregnant serum. Neutrophils were more prominent in HG specimens than in PEP specimens; extracellular neutrophil elastase was minimally present and similar in both diseases. Mast cell numbers and extracellular tryptase deposition did not differ between the two diseases and did not differ from mast cell counts in skin of normal pregnant women. This study shows that eosinophil granule proteins are deposited extracellularly in tissue and are increased in serum in both PEP and HG. Moreover, eosinophil involvement in the two diseases is more consistent than neutrophil and mast cell involvement. Comparatively, tissue eosinophil infiltration and extracellular protein deposition is more extensive in HG than in PEP, suggesting that eosinophil involvement is greater in the pathogenesis of HG than PEP and similar to that found in bullous pemphigoid.

Decreased interleukin-7 and transforming growth factor-beta1 levels in blister fluids as compared to the respective serum levels in patients with bullous pemphigoid. Opposite behavior of TNF-alpha, interleukin-4 and interleukin-10

This study analyzes both the blister fluid (BF) and serum levels of IL-7 and TGF-beta1 in samples from 18 patients affected with bullous pemphigoid (BP). These cytokines clearly present lower concentrations (P<0.001) in BFs than in the sera (1/20 and 1/2, respectively). In contrast, TNF-alpha, IL-10 and IL-4 present increased amounts in BFs that were 12, 12 and 17-fold, respectively. Eighteen sera (and 10 suction BF) from normal individuals were also employed as control. Normal sera presented significantly lower serum IL-7 concentrations than BP, while no significant TGF-beta1 variations were observed between normal and pathologic serum samples. In addition, the serum levels detected in BP patients were significantly correlated with disease intensity (r=0.64, P=0.003, evaluated as the number of blisters/erosions for each patient) as well as with the peripheral B-lymphocyte counts (r=0.80, P<0.001) and antibodies directed against the basement membrane zone (r=0.65, P<0.005). Although a clear explanation of this phenomenon is lacking, the data presented in this report agree with a strong decrease of IL-7 production at the local level (keratinocyte is known to produce IL-7 and the latter is known to be down-regulated by IL-10, and in other models also by TGF-beta1 and IL-4, whose levels are elevated in BP BFs) as opposed to an increased peripheral release of the same modulator. The IL-7 reduction may have a biological relevance in controlling a chronic, progressive disease.

Cytokine pattern in blister fluid and serum of patients with bullous pemphigoid: relationships with disease intensity

Few and contrasting data are available in the literature concerning the levels of various cytokines in blister fluid (BF) and in the serum of patients affected with bullous pemphigoid (BP). Using commercially available ELISA kits, this study reports the levels of 11 cytokines detected both in BF and sera of 15 BP patients and compares them with those of 15 control subjects' sera. Generally, no significant differences were observed in BP and control sera. In contrast, interleukin (IL) 1 beta, IL-2, IL-4, IL-5, IL-6, IL-8, tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) showed increased BF levels as compared with BP sera. Two cytokines, IL-11 and IL-12 did not show significant differences between BP BF and sera, while an opposite behaviour was observed for transforming growth factor beta 1 (TGF-beta 1), whose serum levels were higher than the concentrations in BF. Using the number of lesions of the patients as a possible disease intensity marker, significant correlations were found with the BF levels of IL-1 beta, IL-8, TNF-alpha and, most closely, IL-5. These data may have pathogenetic relevance and suggest the possibility that these biological modulators may be used as a quantitative marker of disease intensity.

A case of bullous pemphigoid in a patient on hemodialysis

We describe a case of bullous pemphigoid (BP) in a patient with chronic renal failure maintained on hemodialysis. We diagnosed BP by histopathological and immunofluorescence studies. The relationship between BP and chronic renal failure and/or hemodialysis is not clear, but we believe that immune disarrangement due to chronic renal failure and/or hemodialysis may have influenced the pathogenesis of BP in our case.

Increased serum levels of interleukin (IL)-5, IL-6 and IL-8 in bullous pemphigoid

Some cytokines have been suggested to take part in the blister formation in bullous pemphigoid (BP). However, the roles of the cytokines are only partly understood. To elucidate the involvement of cytokines in the immunological mechanisms in BP, we investigated the serum levels of interleukin (IL)-2, IL-4, IL-5, IL-6, IL-8, IL-13, soluble IL-2 receptor and soluble CD23 in patients with BP, and the correlation between cytokine levels and other clinical and laboratory data. Serum levels of these cytokines and soluble receptors were determined by enzyme-linked immunosorbent assay in 19 patients with BP and in 16 normal control subjects. Serum levels of IL-5 (P < 0.0001), IL-6 (P < 0.01) and IL-8 (P < 0.05) were significantly higher in BP patients than in the control subjects. Other cytokines and soluble receptor levels were not significantly different. Serum levels of IL-6 (P < 0.05) and IL-8 (P < 0.05) were significantly decreased after treatment when skin lesions disappeared. These results suggest that serum levels of IL-6 and IL-8 could be indicators of disease activity of BP.

Detection of elevated levels of IL-4, IL-6, and IL-10 in blister fluid of bullous pemphigoid

Bullous pemphigoid (BP) is an autoimmune subepidermal blistering disease with autoantibodies directed against antigens associated with hemidesmosomes of basal keratinocytes. In addition to autoantibodies and activated complement, cellular mechanisms are crucial for blister formation in this disease. Mononuclear cells, which are the first cells infiltrating BP lesions, mainly belong to CD3, CD4+ T-helper (Th) cells. Elevated concentrations of IL-2, IFN gamma, TNF beta, and IL-5 have been recently demonstrated in BP blister fluid. In this study, we were interested in levels of other Th-type cytokines, including IL-3, IL-4, IL-6, IL-10, and GM-CSF in blister fluid of BP. Cytokines were determined by ELISA or bioassay. Levels in the blister fluid from ten BP patients were compared with those in serum samples taken at the time of blister puncture and with those in suction blister fluid of ten healthy volunteers. In blister fluid of BP, we found significantly elevated concentrations of IL-4, IL-6, and IL-10 relative to both concurrent serum samples and suction blister fluid from controls. No differences were detected for either IL-3 or GM-CSF. Our results suggest that IL-4, IL-6, and IL-10 are released at the site of blister formation in BP.