Marta Wagner

Association of the HLA‐G gene polymorphism with multiple sclerosis in a Polish population

In this study, three polymorphic sites in the HLA‐G gene: −725C>G>T, −716T>G and 14bpindel were genotyped. Significant differences were found between patients and controls in the alleles and genotypes for −725C>G>T and in three‐point haplotypes. We observed also a significant difference in the age of disease onset between patients positive and negative for 14bpins. The results suggest that single nucleotide polymorphisms in the promoter of the HLA‐G gene (mainly −725C>G>T), and 14bpindel, or some genetic marker in tight linkage disequilibrium with them are associated with multiple sclerosis.

Association of PTPN22 single nucleotide polymorphism with rheumatoid arthritis but not with allergic asthma.

PTPN22 gene encodes a lymphoid tyrosine phosphatase (LYP), an important negative regulator of T-cell responses. The 1858C>T (Arg620Trp) single nucleotide polymorphism (rs2476601) was found associated with autoimmune diseases, including rheumatoid arthritis (RA). Allergic diseases are similar to autoimmune diseases, by an exaggerated immune response to an antigen (allergen in this case) normally not invoking such response in healthy individuals. We investigated whether polymorphism 1858C>T in PTPN22 gene is associated with susceptibility to allergic asthma and RA in a Polish population. PTPN22 was genotyped in 173 patients with RA, in 198 patients with allergic asthma, and in 543 controls using PCR-RFLP. The patients with RA differed from healthy controls in frequencies of PTPN22 1858C>T alleles (P=0.0004; odds ratio (OR), 1.8; 95% CI, 1.33–2.55) and genotypes (P=0.0009). Strong associations of 1858T allele with RA limited to joints (0.21 vs 0.12, P=0.0002; OR, 2.1; 95% CI, 1.44–3.00), with erosive disease (0.20 vs 0.12, P=0.0003; OR, 1.92; 95% CI, 1.34–2.71), with a lack of rheumatoid factor (RF; 0.23 vs 0.12, P=0.0008; OR, 2.29; 95% CI, 1.44–3.63), and weak association with the presence of RF (0.17 vs 0.12, P=0.02; OR, 1.6; 95% CI, 1.10–2.40) in comparison with healthy controls were observed. Very strong association of 1858T allele (P<0.0001; OR, 2.72; 95% CI, 1.9–3.9) and T phenotype (P<0001; OR, 3.2; 95% CI, 2.1–4.9) with antibodies to cyclic citrullinated peptide (CCP) was found. When patients with allergic asthma were typed for PTPN22 1858C>T polymorphism, no difference with control was found. Subdivision of patients into those with mild, moderate, or severe asthma did not reveal any associations. In conclusion, we confirmed associations between several clinical manifestations of RA and PTPN22 1858T allele. However, no association with 1858C>T polymorphism was found for susceptibility to allergic asthma or for severity of the disease.

Killer Immunoglobulin-like Receptor (KIR) and HLA Genotypes Affect the Outcome of Allogeneic Kidney Transplantation

Background Recipient NK cells may detect the lack of recipients (i.e., self) HLA antigens on donor renal tissue by means of their killer cell immunoglobulin-like receptors (KIRs). KIR genes are differently distributed in individuals, possibly contributing to differences in response to allogeneic graft. Methodology/Principal Findings We compared frequencies of 10 KIR genes by PCR-SSP in 93 kidney graft recipients rejecting allogeneic renal transplants with those in 190 recipients accepting grafts and 690 healthy control individuals. HLA matching results were drawn from medical records. We observed associations of both a full-length KIR2DS4 gene and its variant with 22-bp deletion with kidney graft rejection. This effect was modulated by the HLA-B,-DR matching, particularly in recipients who did not have glomerulonephritis but had both forms of KIR2DS4 gene. In contrast, in recipients with glomerulonephritis, HLA compatibility seemed to be much less important for graft rejection than the presence of KIR2DS4 gene. Simultaneous presence of both KIR2DS4 variants strongly increased the probability of rejection. Interestingly, KIR2DS5 seemed to protect the graft in the presence of KIR2DS4fl but in the absence of KIR2DS4del. Conclusions/Significance Our results suggest a protective role of KIR2DS5 in graft rejection and an association of KIR2DS4 with kidney rejection, particularly in recipients with glomerulonephritis.

6.7-kbp deletion in LILRA3 (ILT6) gene is associated with later onset of the multiple sclerosis in a Polish population

Recently published studies have implicated the deletion polymorphism in LILRA3 gene, as being associated with multiple sclerosis (MS). A total of 309 patients diagnosed with MS and 379 unrelated healthy volunteers were typed for 6.7-kbp deletion in LILRA3 gene. Simultaneously, presence or absence of HLA-DRB1(∗)1501 allele was established to assess the possibility of interaction between LILRA3 deletion and HLA-DRB1(∗)1501 status. In contrast to previous reports, we did not find any association of LILRA3 deletion with MS susceptibility. Also, the HLA-DRB1(∗)1501 stratification analysis showed no LILRA3 association with the disease. However, we observed that patients negative for the deletion may begin to suffer from MS significantly earlier than patients who are positive (p = 0.014). Similarly to the most European populations we found significantly higher frequency of HLA-DRB1(∗)1501 allele in cases than we found in controls (27.0% vs. 12.5%; p < 0.0001, OR = 2.6, 95%CI = 1.96-3.42).

ALCAM and CD6 — multiple sclerosis risk factors

ALCAM and CD6 may play an important role in the pathogenesis of multiple sclerosis (MS), since they are involved in the transmigration of leukocytes across the blood-brain barrier. In this study, we confirmed our previous findings about the association of the ALCAM gene with risk, development and progression of MS. Additionally, we showed that in the case of the CD6 gene (encoding receptor of ALCAM) not only polymorphisms but also mRNA expression level are associated with MS. Our analysis revealed that the risk of the disease for AA individuals in rs12360861 was almost 3.0-fold lower in comparison to GG individuals (OR=0.34; CI95%=0.12; 0.81). Moreover, we observed lower expression of CD6 mRNA in patients than in healthy individuals (T(2)2,74=6.678; p=0.002).

ALCAM — Novel multiple sclerosis locus interfering with HLA-DRB1*1501

Activated leukocyte cell adhesion molecule (ALCAM) is a molecule involved in leukocyte migration across the blood-brain barrier which is a key stage in multiple sclerosis (MS) pathogenesis. The present study is the first to report evidence of the association of rs6437585 ALCAM polymorphism with risk and progression of MS. Our investigation revealed that rs6437585CT individuals had higher risk of MS (OR=2.34; 95%CI=1.22-4.51; P=0.011) and over 2 years earlier age of onset (95%CI=0.16-4.41, P=0.036). Moreover, we demonstrated that two ALCAM polymorphisms, rs11559013 and rs34926152, although not associated with MS itself, modify HLA-DRB1*1501 effect. Results obtained from logistic regression analysis showed five-fold lower risk for MS for both rs11559013GA/HLA-DRB1*1501+ and rs34926152GT/HLA-DRB1*1501+ individuals. This observations may suggest protective role against MS for both rs11559013GA and rs34926152GT genotypes in HLA-DRB1*1501 positive individuals.

Polymorphisms in CD28, CTLA-4, CD80 and CD86 genes may influence the risk of multiple sclerosis and its age of onset

CD28/CTLA-4–CD80/CD86 molecules play an important role in the regulation of T cells activation. Defects in proteins involved in this pathway may lead to the development of autoimmune diseases in which T cells are involved. In this case–control study (336 multiple sclerosis (MS) patients and 322 controls) we investigated the possible association of eleven polymorphisms in CD28, CTLA-4, CD80 and CD86 genes with susceptibility to MS and/or its progression. We also took into account HLA-DRB1*15:01 status. Moreover, this study aimed to determine the possible gene-gene interactions between examined SNPs associated with the susceptibility to MS and its outcome. Our investigation revealed that in HLA-DRB1*15:01 negative individuals, G allele in rs231775A NGof CTLA-4 gene was associatedwith higher risk ofmultiple sclerosis. Additionally, the association of rs2715267T NGof CD86 gene withMS susceptibilitywas detected. In details, carriers of G allele at this polymorphic site possessed higher risk of MS in comparison to TT homozygotes. On the other hand, the lower risk of MS was observed in individuals carrying A allele at the rs1599795T N A polymorphic site of CD80. Furthermore, the analysis revealed an interaction between three polymorphisms: rs3116496T N C (CD28), rs6641T N G (CD80) and rs17281995G N C (CD86), associated with the age of MS onset.

Investigation of gene–gene interactions between CD40 and CD40L in Polish multiple sclerosis patients

CD40-CD40L interaction is necessary for the activation of both humoral and cellular immune response and has been suggested to play a role in the pathogenesis of multiple sclerosis (MS). Therefore, we analyzed the combined influence of the CD40 and CD40L variants on MS susceptibility and progression on well-defined Polish population. Our investigation revealed that CT individuals in rs1883832 locus of CD40 possessed almost 1.5-fold higher risk for MS than CC individuals (OR = 1.44; 95%CI = 1.03-2.1; p = 0.032), while this risk for TT individuals was almost 2.5-fold higher (OR = 2.36; 95%CI = 1.19-4.78; p = 0.014). Moreover, for the first time, we observed the association of CD40 gene with MS development and progression. We observed that for the rs1883832CC individuals the age at diagnosis was on average 2 years lower than for the rs1883832CT and rs1883832TT individuals (CI95% = -3.69-(-0.29); p = 0.023). Additionally, we detected that individuals with TT and CT genotypes showed lower risk of developing secondary progressive course in comparison to those with CC genotype. For rs1883832TT individuals this risk was 4-fold lower (HR = 0.24; CI95% = 0.10-0.53; p = 0.00062). Despite the fact that CD40-CD40L pathway plays a key role in development of autoimmune diseases, we were not able to detect gene-gene interactions between CD40 and CD40L polymorphisms associated with multiple sclerosis.

MS risk allele rs1883832T is associated with decreased mRNA expression of CD40

CD40-CD40L interactions mediate T-dependent B cell response and efficient T cell priming. Therefore, genes encoding these molecules are attractive candidates for studies on autoimmune diseases, such as multiple sclerosis (MS), in which activated T and B cells are involved. Thus, we analyzed CD40 and CD40L mRNA expression in whole blood samples from MS patients and controls. Additionally, we examined the effect of three SNPs of CD40 (rs1883832C>T, rs11569343C>G, and rs752118C>T) and two SNPs of CD40L (rs3092923T>C and rs3092952A>G) on their mRNA expression. Our results showed that the rs1883832C>T SNP affects CD40 gene expression. Our analysis revealed that individuals possessing CT and TT genotypes (predisposing to MS) had decreased level of CD40 mRNA in comparison to those with CC. Moreover, we demonstrated the potential role of impaired CD40-CD40L interaction in developing of multiple sclerosis.

Polymorphisms in genes of the BAFF/APRIL system may constitute risk factors of B-CLL – a preliminary study on a Polish population

The association of single-nucleotide polymorphisms (SNPs) of B-cell activating factor (BAFF)/a proliferation-inducing ligand (APRIL) system with B-cell chronic lymphocytic leukemia (B-CLL) have been suggested, therefore, we investigated 20 SNPs of BAFF, APRIL, BAFF-R, transmembrane activator and calcium modulator and cyclophilin-ligand interactor (TACI), B-cell maturation antigen (BCMA) genes and the risk and outcome of B-CLL in 187 patients and 296 healthy subjects as well as ligand-receptor gene × gene interactions. Although the obtained P-values for all 20 SNPs did not reach statistical significance for this study (α = 0.003), the high value of the global chi-squared statistic (χ(2) df = 38  = 52.65; P = 0.0586), and obtained values of odds ratio indicate that rs9514828 (BAFF), rs3803800 (APRIL) and rs4985726 (TACI) may be associated with the risk of B-CLL. We observed that the B-CLL patients with the genotype rs9514828CT/rs11570136AA were diagnosed with the disease 12 years later than the whole group of patients in this study.