Primary alterations during the development of hidradenitis suppurativa.

BACKGROUND: Hidradenitis suppurativa (HS) is a chronic, inflammatory disease of the apocrine gland-rich (AGR) skin region. The initial steps of disease development are not fully understood, despite intense investigations into immune alterations in lesional HS skin. OBJECTIVES: We aimed to systematically investigate the inflammatory molecules involved in three stages of HS pathogenesis, including healthy AGR, non-lesional HS and lesional HS skin, with the parallel application of multiple mRNA and protein-based methods. METHODS: Immune cell counts (T cells, dendritic cells, macrophages), Th1/Th17-related molecules (IL-12B, TBX21, IFNG, TNFA, IL-17, IL10, IL-23A, TGFB1, RORC, CCL20), keratinocyte-related sensors (TLR2,4), mediators (S100A7, S100A8, S100A9, DEFB4B, LCN2, CAMP, CCL2) and pro-inflammatory molecules (IL1B, IL6, TNFA, IL-23A) were investigated in the three groups by RNASeq, RT-qPCR, immunohistochemistry and immunofluorescence. RESULTS: Epidermal changes were already detectable in non-lesional HS skin; the epidermal occurrence of antimicrobial peptides (AMPs), IL-1ß, TNF-α and IL-23 was highly upregulated compared with healthy AGR skin. In lesional HS epidermis, TNF-α and IL-1ß expression remained at high levels while AMPs and IL-23 increased even more compared with non-lesional skin. In the dermis of non-lesional HS skin, signs of inflammation were barely detectable (vs. AGR), while in the lesional dermis, the number of inflammatory cells and Th1/Th17-related mediators were significantly elevated. CONCLUSIONS: Our findings that non-lesional HS epidermal keratinocytes produce not only AMPs and IL-1ß but also high levels of TNF-α and IL-23 confirm the driver role of keratinocytes in HS pathogenesis and highlight the possible role of keratinocytes in the transformation of non-inflammatory Th17 cells (of healthy AGR skin) into inflammatory cells (of HS) via the production of these mediators. The fact that epidermal TNF-α and IL-23 appear also in non-lesional HS seems to prove these cytokines as excellent therapeutic targets.

Improvement of clinical and immunological parameters after allergen-specific immunotherapy in atopic dermatitis.

BACKGROUND: Allergen immunotherapy (AIT) is considered a curative treatment in some atopic diseases, but in AD contradictory clinical results exist and the action of AIT has not been elucidated. In the literature, there is no evidence for parallel investigations of permeability barrier, cutaneous and blood immune responses after AIT in AD. OBJECTIVES: The objective was to investigate immune parameters in the blood and skin and to detect clinical and barrier changes after AIT in AD. METHODS: Mild-to-moderate AD patients (n = 14) with concomitant allergic rhinitis to house dust mites were selected. All patients received topical treatment, while eight patients were randomly selected for adjuvant AIT also. At baseline and after 6 months, clinical, barrier and immunological investigations (serum and skin tests) were performed. In selected patients, biopsies from atopy patch tests (APTs) were analysed by immunohistochemistry for AD-relevant immune cells and mediators. RESULTS: In the adjuvant AIT group, clinical parameters and barrier functions improved significantly. Blood immune parameters displayed no significant changes. Post-AIT APT became negative in all patients in the AIT group, but remained positive in the non-AIT group. Cutaneous dendritic cell and T-cell recruitment decreased significantly after allergen challenge in the AIT group, but no significant changes in skin or serum immunoglobulin E levels or prick test (SPT) reactivity were detected. CONCLUSIONS: Allergen immunotherapy is a beneficial adjuvant treatment for sensitized AD patients. AIT improves not only clinical symptoms, but also permeability barrier functions. The effect of AIT on sensitization should be detected by APT, not by SPT.

Severe skin inflammation and filaggrin mutation similarly alter the skin barrier in patients with atopic dermatitis.

BACKGROUND: Filaggrin (FLG) deficiency is a well-known predisposing factor for the development of atopic dermatitis (AD). Decreased FLG expression can be the result of haploinsufficiency or severe inflammation, which can cause acquired FLG alterations. FLG mutations are related to several clinical and laboratory parameters of AD; however, some recent data seem to contradict these associations. OBJECTIVES: Our aim was to determine which clinical and biochemical parameters are connected to FLG haploinsufficiency and which ones are also associated with acquired FLG alterations due to severe skin symptoms in patients with AD. METHODS: We introduced a novel classification of patients with AD, based on FLG mutations and SCORAD (SCORing Atopic Dermatitis). Based on these parameters, we created three groups of patients with AD: mild-to-moderate wild-type (A), severe wild-type (B) and severe mutant (C). In all groups, we assessed laboratory and clinical parameters and performed immunohistochemical analyses. RESULTS: Groups B and C contained patients with equally severe symptoms based on the SCORAD. The two severe groups did not differ significantly with respect to barrier-specific parameters, whereas group A had significantly better results for the barrier function measurements. However, significant differences were detected between groups B and C with respect to the allergic sensitization-specific parameters. CONCLUSIONS: These findings suggest that skin barrier function correlates with the severity of skin inflammation and can be equally impaired in patients with FLG mutant- and wild-type AD with severe symptoms. Nevertheless, our results also suggest that patients with FLG mutant-type AD may have a higher risk of allergic sensitization compared with patients with the wild-type.

Interaction of HLA-DRB1*03 and smoking for the development of anti-Jo-1 antibodies in adult idiopathic inflammatory myopathies: a European-wide case study.

OBJECTIVES: HLA-DRB1*03 is strongly associated with anti-Jo-1-positive idiopathic inflammatory myopathies (IIM) and there is now increasing evidence that Jo-1 antigen is preferentially expressed in lung tissue. This study examined whether smoking was associated with the development of anti-Jo-1 antibodies in HLA-DRB1*03-positive IIM. METHODS: IIM cases were selected with concurrent information regarding HLA-DRB1 status, smoking history and anti-Jo-1 antibody status. DNA was genotyped at DRB1 using a commercial sequence-specific oligonucleotide kit. Anti-Jo-1 antibody status was established using a line blot assay or immunoprecipitation. RESULTS: 557 Caucasian IIM patients were recruited from Hungary (181), UK (99), Sweden (94) and Czech Republic (183). Smoking frequency was increased in anti-Jo-1-positive IIM cases, and reached statistical significance in Hungarian IIM (45% Jo-1-positive vs 17% Jo-1-negative, OR 3.94, 95% CI 1.53 to 9.89, p<0.0001). A strong association between HLA-DRB1*03 and anti-Jo-1 status was observed across all four cohorts (DRB1*03 frequency: 74% Jo-1-positive vs 35% Jo-1-negative, OR 5.55, 95% CI 3.42 to 9.14, p<0.0001). The frequency of HLA-DRB1*03 was increased in smokers. The frequency of anti-Jo-1 was increased in DRB1*03-positive smokers vs DRB1*03-negative non-smokers (42% vs 8%, OR 7.75, 95% CI 4.21 to 14.28, p<0.0001) and DRB1*03-positive non-smokers (42% vs 31%, p=0.08). In DRB1*03-negative patients, anti-Jo-1 status between smokers and non-smokers was not significantly different. No significant interaction was noted between smoking and DRB1*03 status using anti-Jo-1 as the outcome measure. CONCLUSION: Smoking appears to be associated with an increased risk of possession of anti-Jo-1 in HLA-DRB1*03-positive IIM cases. The authors hypothesise that an interaction between HLA-DRB1*03 and smoking may prime the development of anti-Jo-1 antibodies.

Frequencies of genetic polymorphisms of TLR4 and CD14 and of HLA-DQ genotypes in children with celiac disease, type 1 diabetes mellitus, or both.

OBJECTIVES: Besides the central role of the adaptive immune system, a disturbance of innate immunity is also involved in the pathogenesis of celiac disease (CD). Inasmuch as CD and type 1 diabetes mellitus (T1DM) frequently coexist because of a common genetic predisposition, our aim was to study the frequency of CD14 C-260T and TLR4 A+896G single nucleotide polymorphisms (SNPs) and the distribution of HLA-DQ genotypes in children affected by CD, T1DM, or both. PATIENTS AND METHODS: TLR4 and CD14 SNPs were tested by polymerase chain reaction, followed by restriction fragment length polymorphism analysis in 80 children with T1DM, 100 children with CD, and 47 children with both CD and T1DM. Determination of HLA-DQ alleles was done by sequence-specific polymerase chain reaction. Frequencies were compared with those of healthy control children. RESULTS: The prevalence of the homozygous CD14 C-260TT genotype was significantly (P = 0.0081) lower in children with T1DM but not in those with CD and T1DM, compared with control children. No difference was found in the genotype and allele frequencies of TLR4 between the studied groups. In patients with T1DM, the frequency of the homozygous HLA-DQ8 genotype was significantly higher than in CD, whereas the frequency of homozygous or heterozygous HLA-DQ2 genotypes did not differ from that in control children. In patients with CD, both homozygous and heterozygous HLA-DQ2 genotypes were significantly more frequent than in the control and T1DM groups, and no elevation in the frequency of the HLA-DQ8 genotypes was observed. In patients with T1DM and those with CD and T1DM, the occurrence of HLA-DQ2/8 heterozygosity was significantly higher than in children with CD only and in control children. CONCLUSIONS: Our results suggest that in patients with T1DM, the CD14 C-260TT homozygous genotype increases the risk for the development of CD. The distribution of HLA-DQ genotype is different in children with CD and T1DM than in children with CD or T1DM only. Determination of the HLA-DQ genotype in children with T1DM may help in estimating the risk for the development of CD.

Anti-cyclic citrullinated peptide antibody isotypes in rheumatoid arthritis: association with disease duration, rheumatoid factor production and the presence of shared epitope.

OBJECTIVE: Anti-cyclic citrullinated peptide (anti-CCP) antibodies of IgG isotype are specific diagnostic markers of rheumatoid arthritis (RA). Recent evidence also points to their direct involvement in the pathophysiology. Little information is available, however, regarding the isotype distribution of anti-CCP antibodies and the characteristics of IgA and IgM anti-CCP. METHODS: IgG, IgA and IgM anti-CCP2 and rheumatoid factor (RF) levels were measured in the sera of 119 RA patients and 118 controls, including patients with other rheumatic diseases and healthy subjects. We analyzed the diagnostic performance of IgA and IgM anti-CCP2 antibodies and their relationship with IgG anti-CCP2, RFs, disease duration and the presence of HLA-DRB1 shared epitope (SE) alleles. RESULTS: Patients with RA had significantly higher serum IgA and IgM anti-CCP2 antibody levels than healthy subjects and patients with other rheumatic diseases (p<0.0001). IgG, IgA and IgM anti-CCP2 antibodies were present in 74.8%, 52.9% and 44.5% of RA patients, and their diagnostic specificity was 95.8%, 95.8% and 91.6%, respectively. The presence of anti-CCP2 antibodies was significantly associated with SE alleles (p=0.03). The frequency of IgM anti-CCP2 positivity was lower in longstanding disease compared to early RA (p=0.03). CONCLUSION: IgA and IgM anti-CCP2 antibodies are present in RA patients, and they are similarly specific for RA as IgG anti-CCP2. The higher frequency of IgM anti-CCP2 antibodies in early RA suggests that they are mostly generated during the first phase of immune response; nonetheless, their production seems to be sustained in some patients. Further analysis of IgM and IgA anti-CCP2 antibodies may provide insights into the pathogenesis of RA.

Systemic sclerosis-rheumatoid arthritis overlap syndrome: a unique combination of features suggests a distinct genetic, serological and clinical entity.

OBJECTIVE: To determine the genetic, clinical and serological characteristics of systemic sclerosis (SSc)-rheumatoid arthritis (RA) overlap syndrome. METHODS: Clinical manifestations and immunolaboratory features of 22 SSc-RA patients were assessed. The HLA-DR genotype of the 22 SSc-RA patients determined by SSP-PCR was compared with that of 38 SSc patients, 100 RA patients and 50 healthy controls. RESULTS: All overlap patients fulfilled the American College of Rheumatology (ACR) criteria for SSc and RA. Five of the 22 patients (23%) had diffuse cutaneous SSc (dcSSc) and 17 patients (77%) had limited cutaneous SSc (lcSSc). Antinuclear antibody, anti-Scl70, IgM rheumatoid factor and anti-CCP antibody positivity were detected in 22 (100%), 5 (23%), 16 (73%) and 18 patients (82%), respectively. Seventeen patients (77%) had pulmonary fibrosis, 12 (55%) had oesophageal dismotility, 11 (50%) had cardiac and five (23%) had renal involvement. Hand joint destruction was observed in 18 patients (82%). Significantly increased frequencies of HLA-DR3 (36% vs 5%), HLA-DR7 (9% vs 4%), HLA-DR11 (36% vs 7%) and HLA-DRw53 (23% vs 5%) were observed in SSc-RA compared with RA patients (P < 0.05). Allele frequencies of the 'shared epitope' (HLA-DR1 and -DR4) were significantly increased in SSc-RA (32% and 27%, respectively) and RA patients (46% and 31%, respectively) in comparison with SSc patients (10.5% and 16%, respectively) or healthy controls (16% and 14%, respectively) (P < 0.05). CONCLUSIONS: To date this is the largest SSc-RA overlap cohort. Genetics, clinical and immunolaboratory features suggest a mixed phenotype. Our data suggest that SSc-RA overlap syndrome may be a distinct genetic, immunological and clinical entity.

Diagnostic significance of HLA-DQ typing in patients with previous coeliac disease diagnosis based on histology alone.

BACKGROUND: Coeliac disease is strongly associated with human leukocyte antigen (HLA)-DQ2 or DQ8 genotypes. The diagnosis is based on demonstrating crypt-hyperplastic villous atrophy, endomysial or transglutaminase antibodies and correlation of disease activity with gluten intake. AIM: To evaluate the clinical utility of HLA-DQ typing, when coeliac disease diagnosis had previously been established solely by histology. METHODS: HLA-DQ alleles, endomysial and transglutaminase antibodies were investigated and histology slides reviewed in 70 patients diagnosed 2-25 years earlier by small-intestinal biopsy but without measuring endomysial or transglutaminase antibodies. Patients without DQ2 or DQ8 or without unequivocal villous atrophy were followed-up on free diet by using serology and biopsies. RESULTS: All 40 endomysial/transglutaminase antibodies positive patients carried DQ2 or DQ8, and 39 of them had severe villous atrophy. Only 56% of patients without endomysial or transglutaminase antibodies positivity had DQ2 or DQ8 (P < 0.001). Seropositivity and relapse developed in 4 of 11 DQ2 positive but in none of 15 DQ2 and DQ8 negative patients on long-term gluten exposure. CONCLUSIONS: Coeliac disease diagnosis based solely on histology is not always reliable. HLA-DQ typing is important in identifying DQ2 and DQ8 negative subjects who need revision of their diagnosis, but it does not have additive diagnostic value if endomysial positivity is already known.