Type 1 diabetes (T1D) is an autoimmune disease characterized by the destruction of pancreatic β-cells. Environmental factors are widely considered to play a major role in the pathophysiology of T1D. Mycobacterium avium subspecies paratuberculosis (MAP) has been proposed as a potential T1D trigger based on the molecular mimicry mechanism and immune cross-reactivity with pancreatic autoantigens. Furthermore, several lines of evidence have recently highlighted the crucial role of Human Endogenous Retroviruses (HERVs) reactivation in multiple autoimmune diseases. Previous studies have demonstrated the presence of antibodies targeting several immunodominant epitopes of MAP and HERV in the serum of T1D patients; however, no data on these antibodies have been reported in Tunisian patients. Therefore, the present study aims to explore the involvement of MAP and HERV in T1D pathology in the Tunisian population. Indirect enzyme-linked immunosorbent assays (ELISA) was performed to evaluate the humoral immune response against MAP epitopes (MAP3865c(125–138), MAP3865c(133–141), MAP2404c(70–85), MAP1,4-α-gbp(157–173)) and their human homologous peptides in Zinc transporter 8 (ZnT8(178–186), ZnT8(186–194)) and in Proinsulin (PI(41−64)). In addition, we measured the antibody response against epitopes derived from the envelope protein of two HERV families (HERV-Wenv(93–108) and HERV-Kenv(19–37)). The ELISA was conducted using the serum of newly diagnosed T1D children (n = 56), their healthy siblings (n = 19), and unrelated healthy controls (n = 23). Our results revealed a high serum prevalence of antibodies against the selected peptides in T1D patients. Interestingly, the humoral immune reactivity was higher in patients with the most acute complication of T1D, Diabetic ketoacidosis. Moreover, antibodies directed against MAP and HERV peptides showed a significant, albeit weak, positive correlation with neutrophil count and neutrophil-to-lymphocyte ratio (NLR). Our findings support the hypothesis that MAP and HERV reactivation may be linked to the onset and severity of T1D.

Pemphigus foliaceus (PF) is a multifactorial skin disease. Substantial evidence for microbiota dysbiosis in skin disorders was gradually revealed. In PF patients' skin lesions, we characterized the profile of microbial communities and the expression of microbial peptides. Using real-time reverse transcriptase PCR and immunohistochemistry, skin lesions were analyzed for gene and protein expression of human β-defensin (hBD) 1, 2, and 3, cathelicidin (LL-37), RNAse-7, and psoriasin. Bacterial 16S rRNA gene sequencing was used for assessing skin microbial communities in 15 samples from PF patients' lesioned skin and 11 PF patients' non-lesioned skin. Gene expression of hBD 2 and 3 and psoriasin were significantly downregulated in skin samples from remittent patients compared to chronic or de novo diagnosed patients. Protein expression of hBD 2, Psoriasin, and LL-37 was increased in skin from de novo patients compared to skin from healthy donors showing markedly different distribution patterns. The skin microbial analysis revealed a substantial difference in microbiome diversity between lesioned and non-lesioned skin of de novo PF patients and, non-lesioned skin of remittent patients. In addition, microbiome diversity within samples of lesioned skin from de novo PF patients showed lower diversity with a lower abundance of specific bacterial genera, namely Dermabacter, Psychrobacter, and Bradyrhizobium. Thus, there is a noticeable over-representation of Staphylococcus and decreased richness in the bacterial communities of PF-active skin lesions. Our data supports the hypothesis that active skin lesions in PF patients exhibit alterations in skin bacterial diversity interlinked with increased expression of AMPs.

Immune checkpoint pathways regulating T cell activity are key targets in cancer therapy. Genetic variations in checkpoint molecules (CTLA-4, PD-1, PD-L1) can alter signaling pathways, affecting cancer risk and treatment response in various types of malignancies. This study aimed to investigate associations between common polymorphisms in immune-regulating genes (CTLA-4, PDCD1 and CD274) and susceptibility to nasopharyngeal carcinoma (NPC) in the Tunisian population. We analyzed six polymorphisms: rs231775 and rs3087243 (CTLA-4), rs2227981, rs2227982, and rs36084323 (PDCD1), and rs2890658 (CD274) in a case–control study which enrolled 61 Tunisian NPC patients and 150 matched healthy controls using the PCR-RFLP method. For the rs231775 SNP, our findings showed a significant association between the AA genotype and increased NPC susceptibility in the recessive model (GG + AG vs. AA) (pc=0.006, OR = 2.5, 95

Glucocorticoids (GC) are the main treatment for pemphigus foliaceus (PF). The effects of GC are mediated through glucocorticoid receptors (GR), with GRα and GRβ being the most significant isoforms. Several molecules are involved in mediating the cellular response to GC and can affect the response to treatment. However, the relationship between sensitivity to GC and the expression of GRα, GRβ, FKBP5, FKBP4, HAT1 and HDAC2 in PF disease has not yet been studied. The purpose of this study was to determine the expression of these molecules in patients with different types of response to treatment. Quantitative real-time PCR was used for gene expression profiling in systemic and cutaneous levels. The protein expression levels of GRα and GRβ and FKBP5 was accomplished through immunohistochemical staining. We studied the association of rs1360780 > FKBP5 SNP with PF disease using TaqMan SNP genotyping. Our findings showed downregulation in the gene expression levels of GRα (p = 0.016), HDAC2 (p = 0.004) and FKBP5 (p = 0.032) genes in PF patients compared to healthy controls in PBMC and an up-regulation in GRα (p = 0.041) and HAT1 (p = 0.008) in remittent patients compared to newly diagnosed patients in skin biopsies. GRα and GRβ proteins were less abundant at the cytoplasmic level in patients (p = 0.048 and 0.005, respectively). The nuclear score of FKBP5 was downregulated in patients (p = 0.028). Moreover, our results revealed that the rs1360780 > T allele is a risk factor to the endemic PF form. This study reported for the first-time the involvement of GRα, GRβ, FKBP5, FKBP4, HAT1 and HDAC2 in PF disease in Tunisian population.

Objective Pancreatic beta cell destruction is a hallmark of type 1 diabetes (T1D), a heterogeneous disorder with a wide range of potential causes. T cell activation molecules have been shown to play an important role in the development of T1D, according to the majority of studies. Some autoimmune diseases have been linked to SNPs in the 4q27 region, specifically in the KIAA1109-interleukin 2 (IL2)-IL21 block. The purpose of this research was to look into how certain polymorphic variants in the 4q27 region are linked to T1D. Methods We investigated whether variants in the 4q27 region could be a causal factor in T1D susceptibility. Polymorphisms of ten single-nucleotide polymorphisms (SNPs) belonging to the KIAA1109/IL21/IL2 block were studied in 255 individuals from 59 families using the Sequenom MassARRAY platform. Results The IL21/IL2 region was found to have a significant association with T1D in Tunisian cohorts. We found that the T allele of the rs2221903 marker is disproportionately passed down from parents to their children. In addition, haplotype analyses encompassing all of the SNPs under consideration show that the GACAGGA and the shortly TT haplotypes were significantly over-transmitted from parents to their children, suggesting they may be a T1D genetic susceptibility factor in our population. Conclusion Several autoimmune disorders (ADs) have been linked to the IL2/IL21 genes, suggesting that there is a shared genetic background that confers a common genetic predisposition across ADs. More research into the genetic and functional aspects of the 4q27 region is needed to better explain the role it plays in the risk of ADs.

Vitamin D dysregulation has been recognized as a factor that may cause or aggravate autoimmunity. Vitamin D deficiency was found to be common in pemphigus vulgaris (PV) in different populations. This study aimed to investigate the vitamin D-VDR pathway in PV in the Tunisian population. A serological study was carried out to determine the vitamin D status in newly diagnosed PV patients. CYP27B1, CYP24A1 and VDR mRNA expression was assessed using quantitative real-time PCR in peripheral blood mononuclear cells (PBMC) from untreated newly diagnosed and treated PV patients. In addition, a genetic study was accomplished on VDR polymorphisms to investigate the changes in VDR gene expression. Overall, the serological study confirmed the hypovitaminosis D in newly diagnosed PV patients. Vitamin D-VDR pathway gene expression showed downregulation of CYP27B1 and CYP24A1 mRNA in first-discovery patients compared to healthy controls, while VDR mRNA was highly expressed in newly diagnosed PV patients. Moreover, CYP27B1, CYP24A1 and VDR mRNA were significantly upregulated in chronic disease severity groups compared to mild disease groups. The genetic study showed low VDR gene expression in carriers of FokI > CC genotype, which was more frequent among PV patients, and FokI > C-TaqI > C-ApaI > A-polyA > A16 haplotype, suggesting that the VDR gene polymorphisms testing can provide useful information for PV treatment decision-making. In conclusion, our findings underline the impact of vitamin D-VDR pathway disruption in the PV pathophysiology in Tunisian patients.

Several auto-immune diseases have been linked to vitamin D deficiency as a contributing environmental factor. Its pleiotropic effects on the immune system, especially its essential role in maintaining immune tolerance, make the vitamin D pathway of great interest. In this study, we focused on Pemphigus foliaceous (PF) in Tunisian population. we aimed to quantify the Serum 25[OH]D levels using chemiluminescence assay and to analyze the differential expression of the VDR, CYP27B1 and CYP24A1 genes in the circulating blood cells and lesional skin tissue of PF patients using Q-PCR. A genetic explanation was then sought to explore any direct relationship between tag polymorphisms and the inherited features of PF. Results confirmed a vitamin D hypovitaminosis in Tunisian PF patients. Interestingly, a differential gene expression correlated to the disease stratification was noted. Indeed, at the systemic level, an upregulation of VDR and CYP27B1 genes was observed in healthy controls compared to PF patients. Notably, in lesional skin tissue, the clinical and serological remission phase was correlated with high transcriptional levels of the VDR gene and conversely a drop in expression of the CYP24A1 gene. Genetic analysis indicated the involvement of the most appealing polymorphisms, rs2228570 and poly (A) microsatellite, in PF etiopathogenesis. Indeed, CAC13 haplotype was associated with a higher risk of PF development. Our findings suggest that alterations in the vitamin D-VDR pathway may influence PF physiopathology, making this pathway a potential target for pharmacological modulation, especially for cortico-resistant PF patients.

This study aimed to determine the impact of genetic variation in FKBP prolyl isomerase 5 (FKBP5) on mRNA and protein expression levels, on glucocorticoids (GC) responsiveness and its clinical association in systemic lupus erythematosus (SLE). The genotyping of the FKBP5-rs1360780 was performed using TaqMan SNP genotyping technology. The mRNA expression level in peripheral blood mononuclear cells was evaluated using realtimePCR. The immunohistochemistry staining was used to analyze FKBP5 protein expression level in renal biopsies. A risk association was revealed between rs1360780 > C allele and SLE pathogenesis. We found an upregulation in the FKBP5 mRNA expression level in SLE patients with the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score <= 6 compared to patients with SLEDAI score > 6. Our results revealed an altered renal cell expression of FKBP5 protein in patients with lupus nephritis compared to control samples. However, no association was observed between the FKBP5 and the response to GC treatment. Our study is the first to demonstrate a link between SLE and FKBP5 gene, in terms of mRNA and protein expression levels, and the variant of the SNP rs1360780 in SLE, suggesting a susceptibility role of rs1360780 > C.

BACKGROUND:T helper interplay and cytokines monitoring in auto-immune skin disorders such as Pemphigus Foliaceus (PF) may play a central role in predicting the clinical stratification of the pathology. OBJECTIVES:In order to assess the CD4+ T cell imbalance, (i) this study aims to assess the related immune cells (Th1, Th2, Th17, and Treg cells) as well as the related cytokines (IL-1β, IFNγ, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-17A, IL-17F, IL- 22, TNF-β, and TNFα) in peripheral blood, and [ii] their respective transcription factors in the lesioned skin of PF endemic patients during the clinical course. METHODS:Peripheral blood of 22 PF patients was analyzed by flow cytometry to assess the functional associations of Th cell subpopulations and their characteristic cytokines by multiplex bead assay of 14-plex cytokines. Skin mRNA expression of their associated transcription factors was analyzed using the TaqMan detection system. RESULTS:Our findings revealed that the CD4+ T cell subtypes in PF patients compared to Healthy Controls (HC) were characterized by (i) a similar Th1/Th2 ratio and increased Th17/Treg ratio and (ii) significantly higher plasma levels of Th-17 specific cytokines; IL- 6, IL-8, IL-17A. Higher percentages in Th17 and Treg subtypes and a significant increase in plasma IL-17F levels were maintained in relapsing PF patients, arguing the pivotal role of Th17 cells in PF pathogenesis. Furthermore, our findings pointed out the major contribution of the pro-inflammatory cytokine IL-6. Indeed, in addition to being involved in the initial stages of disease development, IL-6 seems to also be involved in the maintenance of the pathophysiological process, probably through its effect on Th17 differentiation. The skin-relative mRNA expression levels of FOXP3 and TBET were significantly higher in relapsing PF patients compared to de novo PF patients. CONCLUSION:Our results highlight the central role played by Th17 lymphocytes and their related pro-inflammatory cytokines during the clinical course of the disease, reversing the Th1/Th2 dichotomy in PF.

The inducible T-cell costimulator (ICOS) may play an important role in adaptive immunity by regulating the interaction between T cells and antigen-presenting cells. Disruption of this molecule can lead to autoimmune diseases, in particular systemic lupus erythematosus (SLE). In this study, we aimed to explore the possible association between ICOS gene polymorphisms and SLE as well as their influence on disease susceptibility and clinical outcomes. A further objective was to assess the potential impact of these polymorphisms on RNA expression. A case-control study, including 151 patients with SLE, and 291 unrelated healthy controls (HC) matched in gender, and geographical origin, was performed to genotype two polymorphisms located in the ICOS gene: rs11889031 (-693 G/A) and rs10932029 (IVS1 + 173 T/C); using the polymerase chain reaction (PCR)-restriction fragment length polymorphism method. The different genotypes were validated by direct sequencing. The expression level of ICOS mRNA was assessed by quantitative PCR in peripheral blood mononuclear cells of SLE patients and HC. The results were analysed using Shesis and spss.20. Our results revealed a significant association between ICOS gene rs11889031 > CC genotype and SLE disease (codominant genetic model 1, (C/C vs. C/T), p = .001, odds ratio [OR] = 2.18 IC [1.36-3.49]); codominant genetic model 2, (C/C vs. T/T) p = .007, OR = 15.29 IC [1.97-118.5]); dominant genetic model, (C/C vs. C/T + T/T) p = .0001, OR = 2.44 IC [1.53-3.9]). Besides, there was a marginal association between rs11889031 > TT genotype and T allele with a protective role from SLE (recessive genetic model, p = .016, OR = 0.08 IC [0.01-0.63] and p = 7.6904E - 05, OR = 0.43 IC = [0.28-0.66], respectively). Moreover, statistical analysis indicated that the rs11889031 > CC genotype was linked with clinical and serological manifestations of SLE, including blood pressure, and anti-SSA antibodies production in SLE patients. However, the ICOS gene rs10932029 polymorphism was not associated with susceptibility to SLE. On the other side, we did not note any effect of the two selected polymorphisms on the level of ICOS mRNA gene expression. The study showed a significant predisposing association of the ICOS rs11889031 > CC genotype with SLE, in contrast to a protective effect of rs11889031 > TT genotype in Tunisian patients. Our results suggest that ICOS rs11889031 may act as a risk factor for SLE and could be used as a genetic susceptibility biomarker.

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Introduction A combination of genetic, environmental, and immunologic factors contributes to the development of Multiple sclerosis (MS) disease. The IL23/Th17 pathway seems to play an important role in the pathogenesis of this disorder. On the other hand, the immunomodulatory role of vitamin D (Vit D) and its possible involvement in the susceptibility to MS have been well documented. In particular, parameters associated with Vit D metabolism, such as the vitamin D nuclear receptor (VDR) and the activating enzyme (CYP27B1), have been widely studied in this context. Material(s) and Method(s) We conducted a case-control study on a population (n=90) composed of 45 MS patients and 45 healthy controls. Serum levels of 25 (OH) D and IL17A were determined in the two groups. A transcriptional study of VDR, CYP27B1 and IL23R gene expression in PBMC has been performed. Finally, a cell culture step of PBMC with/without VitD stimulation was initiated for MS patients and healthy controls. The production of IL17A was analyzed in the supernatant. Result(s) The serological study has demonstrated that the level of 25(OH)D was significantly lower in the patients' group than the HC, with a severe deficiency detected in more than 60% of MS patients (Vs 25% in HC). Circulating IL17A level was higher in patients compared to controls. The transcriptomic study revealed that the mean expression of the VDR gene was higher in the MS group than in the controls. Interestingly, the expression of the CYP27B1 gene was found to be significantly higher in HC than the MS patients. Regarding the IL23R gene, its expression was significantly higher in MS patients compared to HC. Positive and statistically significant correlations between VDR, CYP27B1 and IL23R gene expression were reported in the study population as well as in the MS group. Interestingly, the preliminary results of the culture step revealed that the IL17A production in the supernatant was higher in the wells supplemented with Vit D in both patients and control groups. Conclusion(s) In conclusion, our study confirmed the reported association of VitD deficiency with MS in our Tunisian population. The expression of the genes involved in the metabolism of this vitamin (VDR and CYP27B1) seems to be inter-correlated and in relation with the IL23/Th17 pathway. The stimulation with VitD tends to inhibit differentiation towards the TH17 pathway.

Despite significant progress in the past decades, sepsis still lacks a specific treatment. Under normal conditions, leucocytes play a critical role in controlling infection and it is suggested that their activity is impaired during sepsis which contribute to the dysregulation of immune reactions. Indeed, in response to infection, several intracellular pathways are affected mainly those regulating the oxidative- inflammatory axis. Herein, we focused on the contribution of NF-kB, iNOS, Nrf2, HO-1 and MPO genes in the pathophysiology of septic syndrome, by analyzing the differential expression of their transcripts in circulating monocytes and neutrophils, and monitoring the nitrosative/oxidative status in septic syndrome patients. Circulating neutrophils of septic patients displayed a significant overexpression of NF-kB compared to other groups. In monocytes, patients with septic shock expressed the highest levels of iNOS and NF-kB mRNA. However, genes involved in cytoprotective response had increased expression in patients with sepsis, in particular, the Nrf2 and its target gene HO-1. Moreover, patient monitoring indicates that the iNOS enzyme expression and NO plasma levels may play a role in assessing the severity of septic conditions. Overall, in either monocytes or neutrophils, we pointed out the major role of NF-κB and Nrf2 in the pathophysiological process. Therefore, therapies targeted to redox abnormalities may be useful for better management of septic patients.

La physiopathologie du pemphigus superficiel (PS) tunisien implique un processus inflammatoire complexe. Certains paramètres hématologiques de l’inflammation ont été étudiés dans de nombreuses pathologies inflammatoires ou auto-immunes et ont démontré leur intérêt particulièrement dans le suivi de l’évolution de ces maladies. Cependant, l’intérêt de ces paramètres n’est pas encore étudié dans le PS. Notre objectif était d’étudier la corrélation des ratios : neutrophiles/lymphocytes (NLR), plaquettes/lymphocytes (PLR) et plaquettes/neutrophiles (PNR) avec l’activité du PS du sud tunisien. Nous avons mené une étude préliminaire rétrospective incluant 30 patients atteints de PS confirmé par des arguments cliniques, histologiques et immunologiques. Les valeurs des ratios NLR, PLR et PNR, déterminés à partir de la numération formule sanguine, ont été analysés en fonction de l’évolution clinique de la maladie (poussée/rémission) et des taux des anticorps anti desmogléine 1 (Ac anti Dsg1) mesurés par ELISA. Nous avons exclu tout patient ayant une condition pouvant interférer avec les paramètres hématologiques (infection, grossesse, anémie…). L’analyse statistique a été réalisée par le logiciel SPSS 23.0. Au total 30 patientes ont été incluses d’âge médian 32 ans [29,5–48,5]. La durée médiane de suivi était de 7 ans [3–10]. Le NLR était significativement plus élevé chez les patientes en poussée par rapport à celles en rémission (médiane : 2,32 [1,54–4,22] vs 1,34 [1,22–1,82] ; p = 0,005). Le PLR était plus élevé en poussée (médiane :122,6 [82,38–185,6] vs 80.16 [73,37–126,17] ; p = 0,07). Alors que le PNR était plus bas en poussée (45,77 [35,17–55,55] vs 55,82 [50,68–69,21] ; p = 0,01). Concernant les Ac anti Dsg1, leur positivité était associée à une poussée de la maladie (p < 0,001) avec une sensibilité de 100 %. Les taux des Ac anti-Dsg1 étaient corrélés positivement au NLR (r = 0,3 ; p = 0,031) et négativement au PNR (r = −0,3 ; p = 0,034). Les aires sous les courbes ROC des Ac anti-Dsg1, NLR et PLR étaient respectivement : AUC = 0,84 ;IC95 % : 0,68–1 ; (p < 0,001) ; AUC = 0,75 ; IC95 % : 0,59–0,91 ;(p = 0,008) et AUC = 0,65, IC95 % : 0,49–0,81, (p = 0,11). La valeur seuil du NLR associé à l’activité du PS était de 1,83 avec une sensibilité de 70 % et une spécificité de 75 %. Nos résultats montrent qu’un NLR élevé et un PNR bas sont des marqueurs de l’inflammation associés à la survenue de poussée chez les patients atteints de PS. Plusieurs études ont rapporté l’association entre l’élévation du NLR et l’activité de certaines maladies inflammatoires(psoriasis) et auto-immunes (pemphigus vulgaire, pemphigoïde bulleuse). Au cours des poussées, les neutrophiles semblent être impliqués dans les phases précoces de l’inflammation. De façon intéressante, nous avons trouvé une corrélation significative positive entre les Ac anti-Dsg1 et le NLR. Ceci suggère leur intérêt potentiel dans le suivi des patients atteints de PS. Leur interprétation doit tenir compte de leur caractère non spécifique avec de possibles interférences. Nos résultats montrent que 2 marqueurs de l’inflammation (NLR et PNR) sont corrélés aux taux des Ac anti Dsg 1 et à la survenue de poussée de PS. Etant des marqueurs simples et disponibles, ils pourraient être utiles dans la détection précoce d’une poussée de PS. Leur intérêt pronostique mérite être mieux étudié.

Pemphigus foliaceous (PF) is a bullous autoimmune skin disease diagnosed through sera and skin analyses. PF severity is associated with maintained anti-Dsg1 sera levels and its prognosis is unpredictable. MicroRNA (miRNA), dynamic regulators of immune function, have been identified as potential biomarkers for some autoimmune diseases. This study aimed to assess the miRNA expression of miR-17-5p, miR-21-5p, miR-146a-5p, miR-155-5p and miR-338-3p using quantitative real-time PCR in peripheral blood mononuclear cells (PBMC) and lesional skin samples from untreated and treated PF patients (both remittent and chronic) over 3 months. Overall, miRNA expression was significantly higher in PBMC than in biopsy samples. Blood miR-21 expression was increased in untreated patients compared to controls and had a diagnostic value with an AUC of 0.78. After 6 weeks, it decreased significantly, similar to anti-Dsg1 antibodies and the PDAI score. In addition, a positive correlation was observed between cutaneous miR-21 expression and the disease activity score. Conversely, cutaneous expressions of miR-17, miR-146a and miR-155 were significantly higher in treated chronic patients compared to remittent ones. The cutaneous level of miR-155 positively correlated with pemphigus activity, making it a potential predictive marker for patients' clinical stratification with an AUC of 0.86.These findings suggest that blood miR-21 and cutaneous miR-155 can be used as supplemental markers for PF diagnosis and activity, respectively in addition to classical parameters.