To determine differences in the blood innate gene expression signatures of systemic lupus erythematosus (SLE) patients across various organ manifestations and disease activity, with a focus on lupus nephritis (LN) and central nervous system (CNS) involvement. Toll-like receptor family (TLR 1–10) mRNA expression was investigated in peripheral blood mononuclear cells from patients with SLE (n = 74) and healthy controls (n = 34). We compared patients with histologically confirmed active LN or neuropsychiatric systemic lupus erythematosus (NPSLE) with patients without these symptoms. The expression of TLR mRNA was determined by RT‒qPCR using a high-throughput SmartChip Real-Time-qPCR system (WaferGen). Multivariate analysis and nonparametric statistics were used for data analysis to assess the associations between TLRs and disease activity and severity. TLR4 (0.044 vs. 0.081, p = 0.012) was upregulated and TLR10 (0.009 vs. 0.006, p = 0.0007) was downregulated in the whole cohort of SLE patients compared to healthy controls. A comparison of the active LN group with participants without kidney involvement revealed increased expression of TLR2 (0.078 vs. 0.03, p = 0.009), and TLR5 (0.035 vs. 0.017, p = 0.03). Moreover, a significant difference was observed in TLR9 expression between inactive LN and the control group (0.014 vs. 0.009, p = 0.01), together with borderline correlation in TLR2 expression (0.04 vs. 0.03, p = 0.06). Receiver operating characteristic (ROC) curve analysis revealed that TLR1 and TLR2 expression were the best potential diagnostic markers for active LN. The NPSLE group showed upregulation of TLR1 (0.088 vs. 0.048, p = 0.01), TLR4 (0.173 vs. 0.066, p = 0.0003) and TLR6 (0.087 vs. 0.036, 0.007). Our correlation analysis supported the close relationships among the expression of individual TLRs in the whole lupus cohort and its subgroups. Our study revealed differences in TLR expression between a lupus cohort and healthy controls. Additionally, our analysis provides insight into specific TLR expression in cases with severe organ manifestations, such as LN and NPSLE. The multiple mutual relationships of TLRs demonstrate the activation of innate immunity in SLE and suggest promising targets for future therapies or diagnostics.

Coeliac disease (CD) is an autoimmune disorder caused by the ingestion of gluten-containing grains. One of the prerequisites for the development of the disease is the presence of specific combinations of HLA alleles at the DQA1 and DQB1 loci. The HLA test is a supportive diagnostic test. In the Czech Republic, approximately 3,500 HLA tests for CD diagnosis are performed annually in almost three dozen laboratories. The HLA Department of the Institute of Haematology and Blood Transfusion in Prague has been offering the EPT “Detection of HLA Alleles Associated with Diseases” for more than 10 years. The results are evaluated in terms of the correct determination of predisposing alleles/allelic groups and clinical interpretation. Every year, we notice some problems with the detection of CD-associated alleles and the interpretation of results. Annual workshops are part of this EPT, and they also include recommendations for the interpretation of results. This interpretation is evolving based on the current knowledge in the field. The current recommendation for interpretation was adopted in 2023, dividing HLA-DQA1/DQB1 genotypes into three categories: 1) detected HLA genotype is associated with predisposition to coeliac disease; 2) coeliac disease could not be excluded based on the detected HLA genotype; 3) coeliac disease could be excluded with high probability based on the detected HLA genotype. The quality of examination is increasing but still needs improvement. Correct results and accurate interpretation can inform clinicians’ decisions about the diagnosis of coeliac disease in appropriate patients.

HLA-A*29:172 allele differs from HLA-A*29:01:01:01 by one missense single C/G nucleotide exchange in codon 77.

Background: Lower gastrointestinal (GI) graft versus host disease (GVHD) represents a severe complication in allogeneic hematopoietic stem cell transplant (HSCT) recipients with high rates of transplant-related mortality. Deregulated innate immunity reactions are the features of its pathogenesis. Cellular senescence has been considered a program of the innate immunity. We focused on lower GI GVHD from the perspective of cellular senescence. Objective: We analyzed the impact of p16INK4a expression, a hallmark of cellular senescence, in intestinal biopsies of patients with lower GI GVHD symptoms and NFKB1 gene polymorphisms (rs3774937 C/T and rs3774959 A/ G) on HSCT outcome.Study design: Fifty-two single-center patients who presented with symptoms of lower GI GVHD were analyzed in a retrospective manner. Two SNPs located in the NFKB1 gene regions (rs3774937 C/T and rs3774959 A/G) were genotyped from the peripheral blood samples collected before the start of the conditioning. All patients underwent proctosigmoidoscopy with biopsy of the mucosa. The expression of p16INK4a was analyzed in normal intestinal crypts and stroma.Results: Fifty-two patients (50% male) received HSCT for hematological diseases (acute leukemias in 67%) and developed lower GI symptoms. Patients with p16INK4a expression in the intestinal stroma were in lower risk of developing histological grade 3-4 aGVHD (RR 0.18 [95% CI 0.05-0.65]; p = 0.009). The multivariate linear regression confirmed the independent effect of p16INK4a expression on time of the lower GI aGVHD symptoms onset (Coef. 38.9 [95% CI 12.7-65.1]; p = 0.005). The NFKB1 rs3774937 CC and TT/TC genotype were present in 40 and 80% of patients with p16INK4a expression, respectively (p = 0.04). The rs3774959 AA and GG/AG genotype were present among 43 and 82% of patients with p16INK4a expression, respectively (p = 0.02). Expression of p16INK4a was associated with no clinical variable but NFKB1 genotype.Conclusions: Our results address possible new mechanisms that may lead to better understanding of HSCT-related immune complications. Cellular senescence may bring novel approaches in GVHD diagnostics and therapy.

HLA-A*29:172 allele differs from HLA-A*29:01:01:01 by one missense single C/G nucleotide exchange in codon 77.

Numerous associations of HLA variants with susceptibility to diseases, namely, those with an immunopathological component, have been described to date. The strongest HLA associations were incorporated into the standard algorithms for the diagnostics. Disease-associated HLA variants are routinely detected by various techniques including DNA-based assays. For the identification of HLA markers or their combinations with the highest diagnostic value and those with frequent clinical indications (e.g., HLA-B*27, -B*57:01, -DQ2/-DQ8, -DQB1*06:02), diagnostic tests that focus on a single or limited number of specific HLA antigens/alleles, have already been developed; the use of complete typing for particular HLA loci is a relevant alternative. Importantly, external proficiency testing (EPT) became an integral part of good laboratory practice for HLA disease associations in accredited laboratories and not only supports correct “technical” identification of the associated HLA variants, but also adequate interpretation of the results to the clinicians. In the present article selected aspects of EPT for HLA disease associations related to population genetics are reviewed and discussed with the emphasis on the optimal level of HLA typing resolution, population-based differences in disease associated HLA alleles within the allelic group, distribution and linkage disequilibrium of HLA alleles in particular populations and interpretation of the presence of less common HLA variants/haplotypes. In conclusion, the laboratories that perform and interpret the tests to the clinicians, producers of the certified diagnostics and EPT providers should consider, among others, the genetic characteristics of the populations in order to optimise the diagnostic value of the tests for disease-associated HLA variants.

HLA‐A*29:172 allele differs from HLA‐A*29:01:01:01 by one missense single C/G nucleotide exchange in codon 77.

Background: BK viral nephropathy (BKVN) affects a significant proportion of kidney grafts in the early post-transplant period and often leads to functional failure of these grafts. The intensity of immunosuppressive therapy plays a significant role in the activation of BK viral (BKV) replication. Methods: 457 per-protocol biopsies of kidney grafts were performed in a group of 161 newly transplanted patients. The incidence of histological signs of tacrolimus nephrotoxicity as a manifestation of excessive immunosuppression was calculated using the Calcineurin Inhibitor Nephrotoxicity Score (CINS). In case of detection of simultaneous toxicity and substantial BKV replication, the dose of tacrolimus and/or mycophenolate was reduced and the effect on the inhibition of BKV activation and regression of toxic changes were compared. In parallel, we studied the effect of pre-emptive reduction of tacrolimus dose on the development of BKV replication in isolated detections of toxicity during the subsequent period. Results: The reduction of tacrolimus and mycophenolate dose in patients with histological evidence of toxicity and significant BKV replication was associated with an early and significant decrease in the BKV plasma load compared to isolated mycophenolate reduction (P = 0.023), significant decrease in CINS (P = 0.001) and better functional parameters at the end of this one-year follow-up (P = 0.024). A pre-emptive dose reduction of tacrolimus in case of toxicity evidence led to a marked reduction in the incidence of substantial BKV viremia during the subsequent period. Conclusions: The reduction of tacrolimus and mycophenolate dose in patients with histologically verified tacrolimus nephrotoxicity represents a more effective approach to attenuate significant BKV replication than a single-dose reduction of mycophenolate, including the regression of toxic changes. Pre-emptive tacrolimus dose reduction in case of toxicity signs is associated with a lower incidence of significant BKV replication during the first year after transplantation, without increasing the risk of acute rejection. Supported by MH CZ – DRO (FNOl, 00098892) and by grant IGA_LF_2022_03.

Cellular senescence is characterized by irreversible cell cycle arrest and pro-inflammatory secretion, mostly regulated by NF-kB. Expression of p16INK4a - a cell cycle inhibitor, is considered a hallmark of cellular senescence. Based on overlapping features observed in inflammatory signaling of both GVHD and cellular senescence, we have postulated a hypothesis whether genetic variants of the NFKB1 gene and expression of p16INK4a in intestinal mucosa of the recipients have impact on transplant-related inflammatory complications. Here we present 52 consecutive patients with symptoms of lower gastrointestinal GVHD after allogeneic stem cell transplantation. The patients were genotyped for GVHD-prone polymorphisms of the NFKB1 gene, rs3774937 C/T and rs3774959 A/G. All patients underwent diagnostic proctosigmoidoscopy with gut mucosa biopsy. Immunohistochemical detection of p16INK4a expression was evaluated in normal intestinal crypts and stroma. On day +14 after graft infusion serum levels of inflammation - associated proteins were analyzed. Increased p16INK4a expression in intestinal crypts was independently associated with late manifestation of lower gastrointestinal symptoms. Patients with and without p16INK4a expression in intestinal crypts developed lower gastrointestinal symptoms in median of 43 days (range,12-140) and 24 days (range,13-80), respectively. The effect was observed in the whole study cohort (HR 2.3 [95%CI 0.99-5.47];p=0.006) as well as in a subgroup of patients who fulfilled the clinical diagnostic criteria of GVHD only (HR 3.1 [95%CI 0.95-10.01];p=0.002). Increased risk of histological grade 3-4 aGVHD was observed in patients without stromal p16INK4a expression (HR 3.45 [95%CI 1.26-9.42];p=0.01). The impact was confirmed by means of multivariate Cox regression (p=0.009). No clinical variable had effect on p16INK4a expression but NFKB1 genotype. The GVHD-prone genotypes rs3774937 CC and rs3774959 AA were significantly less frequent in patients with increased p16INK4a expression (p=0.04 and p=0.02, respectively). In 13 patients, measurement of serum levels of 92 inflammation-associated proteins from the Proseek Multiplex lnflammation - I kit on day +14 after graft infusion was performed. Patients with increased expression of p16INK4a in intestinal crypts at the time of gut biopsy had significantly lower serum levels of proinflammatory proteins (IL-17A, IL-18, IL-4, CXCL10 and TNFRSF9) on day +14. Using the STRING web engine we performed the enrichment analysis with statistically significant confirmation of interactions among these proteins suggesting various T-cell cytokine production or Type -2 immune response from the gene ontology analysis. Cellular senescence is considered a program of innate immunity. In GVHD, innate immunity becomes seriously decontrolled. Cellular senescence may thus bring novel approaches towards GVHD diagnostics and therapy. Supported by Ministry of Health, Czech Republic - conceptual development of research organization (FNOl, 00098892) Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

All renal transplant recipients should undergo a regular screening for BK viral (BKV) viremia. Gradual reduction of immunosuppression is recommended in patients with persistent plasma BKV viremia for 3 weeks after the first detection, reflecting the presence of probable or suspected BKV-associated nephropathy. Reduction of immunosuppression is also a primary intervention in biopsy proven nephropathy associated with BKV (BKVN). Thus, allograft biopsy is not required to treat patients with BKV viremia with stabilized graft function. There is a lack of proper randomised clinical trials recommending treatment in the form of switching from tacrolimus to cyclosporin-A, from mycophenolate to mTOR inhibitors or leflunomide, or the additive use of intravenous immunoglobulins, leflunomide or cidofovir. Fluoroquinolones are not recommended for prophylaxis or therapy. There are on-going studies to evaluate the possibility of using a multi-epitope anti-BKV vaccine, administration of BKV-specific T cell immunotherapy, BKV-specific human monoclonal antibody and RNA antisense oligonucleotides. Retransplantation after allograft loss due to BKVN can be successful if BKV viremia is definitively removed, regardless of allograft nephrectomy.

Graft-versus-host disease (GVHD) represents a significant cause of mortality after allogeneic hematopoietic stem cell transplantation (HSCT). NF-kB system is a master regulator of innate immunity responses. It controls the expression of various cytokines and chemokines many of which are involved in GVHD pathogenesis. Chemo(radio) therapy administered during conditioning induces DNA damage and activates DNA damage response (DDR) signaling resulting in irreversible cell cycle arrest – cellular senescence which has been described to be associated with robust pro-inflammatory secretion mostly controlled by NF-kB. The NFKB1 gene encodes the DNA-binding subunit of the NF-kB complex. Using the candidate gene approach, we analyzed possible association of two single-nucleotide polymorphisms (SNPs) rs3774937 C/T and rs3774959 A/G of the NFKB1 gene with GVHD and transplant-related mortality (TRM) occurrence in 109 recipients allografted from HLA-identical donor. Both SNPs in recipients were found to be strongly associated with acute GVHD. Nevertheless, no significant association with chronic GVHD and TRM was found. Presented pilot results contribute to pre-clinical observations and suggest that NF-kB may be an important regulator of HSCT-related inflammatory reactions such as acute GVHD. Novel pathogenic mechanisms of GVHD may arise from perspectives of DDR and cellular senescence where NF-kB plays an essential role.

Sarcoidosis is a genetically complex systemic inflammatory disease that affects multiple organs. We present a GWAS of a Japanese cohort (700 sarcoidosis cases and 886 controls) with replication in independent samples from Japan (931 cases and 1,042 controls) and the Czech Republic (265 cases and 264 controls). We identified three loci outside the HLA complex, CCL24 , STYXL1-SRRM3 , and C1orf141 - IL23R , which showed genome-wide significant associations ( P < 5.0 × 10 −8 ) with sarcoidosis; CCL24 and STYXL1-SRRM3 were novel. The disease-risk alleles in CCL24 and IL23R were associated with reduced CCL24 and IL23R expression, respectively. The disease-risk allele in STYXL1-SRRM3 was associated with elevated POR expression. These results suggest that genetic control of CCL24 , POR , and IL23R expression contribute to the pathogenesis of sarcoidosis. We speculate that the CCL24 risk allele might be involved in a polarized Th1 response in sarcoidosis, and that POR and IL23R risk alleles may lead to diminished host defense against sarcoidosis pathogens.

Although complex approaches in haematopoietic stem cell transplantation (aHSCT) improved substantially in the last decades, considerable proportion of patients still suffer from life-threatening complications including graft versus host disease (GvHD). Great effort has therefore been dedicated to identification of biomarkers of the aHSCT outcome. Recently, prognostic scores for the prediction of GvHD and non-relapse mortality based on circulating molecules, such as tumour necrosis factor receptor-1, IL-33receptor (ST2) and regenerating islet-derived 3-alpha were proposed and evaluated in multicentre studies. Furthermore, several biomarkers, for example, ST2, represent promising targets for therapeutic intervention in severe GvHD. These results bring us closer to the clinical strategies to effectively control complications following aHSCT, and therefore to the tailored stem cell therapy with higher benefits for the patients.