Association of multispecific red blood cell alloimmunization with HLA-Class II variants is related to Rh phenotypes.

AIM: It remains unclear, why only some patients form alloantibodies against foreign RBC antigens. Transfusion of red blood cell (RBC) products and pregnancy are the most relevant causes of immunization against RBC alloantigens. Here we investigated the relationship between RBC alloantibodies, Rh phenotype, and HLA phenotype among patients with multiple RBC alloantibodiesMETHODS: In a group of 124 multi-responders ‒ including both pregnant women and transplant recipients ‒ we analysed the distribution of HLA-Class II variants in subgroups of multi-responders to RBC alloantigens according to their Rh status. RESULTS: As expected, the RhD-negative phenotype was overrepresented in our alloimmunized group (49.2 %) compared to in the general population. Importantly, HLA-DRB1*15 carriers were significantly overrepresented among D-negative multi-responders compared to D-positive multi-responders (Pc = 0.045). Furthermore, the linked HLA-DRB1*13, HLA-DQB1*06, and HLA-DQA1*01 variants were more frequent in individuals with the DCCee phenotype than in other RhD-positive phenotypes. CONCLUSION: Our present findings showed that RBC multispecific alloimmunization was associated with particular HLA-Class II variants based on Rh status (Tab. 3, Ref. 22).

TP53 rs1042522 and rs8064946 variants in myocardial infarction.

OBJECTIVE: This study investigated the hypothesis that the single nucleotide polymorphisms (SNPs) of TP53 gene are related to a risk of myocardial infarction. METHODS: The coding SNP at codon 72 (rs1042522) and non-coding rs8064946 SNP were genotyped by polymerase chain reaction with sequence specific primers in 205 Czech patients with myocardial infarction and 148 Czech control subjects. RESULTS: The distribution of both SNPs was in agreement with the Hardy-Weinberg equilibrium and was similar to other European populations. Our power analysis showed 96 % of probability to detect an odd ratio equal to 2. Neither rs1042522 nor rs8064946 were associated with the risk of myocardial infarction. The haplotypes combined of rs1042522 and rs8064946 were not associated with myocardial infarction in the present study. CONCLUSION: The TP53 SNPs are not strongly associated with genetic predisposition to myocardial infarction (Tab. 3, Fig. 3, Ref. 23).

Association of HLA-DRB1 and HLA-DQB1 with red-blood-cell alloimmunization in the Czech population.

BACKGROUND AND OBJECTIVES: Alloimmune antibodies against red-blood-cell (RBC) antigens induced in susceptible individuals (responders) by transfusion, pregnancy or transplantation may have serious clinical consequences. The aim of this study was to investigate association of alloimmunization against selected RBC antigens with HLA-Class II. MATERIALS AND METHODS: A total of 230 responders (106 monoresponders and 124 multiresponders) were enrolled into the study. HLA-DRB1 and HLA-DQB1 variants were determined by PCR-SSO and their frequencies compared between the patients (patient subgroups) and 375 ethnically and regionally matched controls. RESULTS: Development of multiple RBC antibodies was associated with HLA-DRB1*15 and HLA-DQB1*06 allelic groups in the patients, with the relationship being particularly apparent in those with anti-C+D antibodies. Furthermore, DRB1*13 and DQB1*06 were more frequent in multiresponders with anti-E+c antibodies and DRB1*03 and DQB1*02 in those with anti-E+Cw. CONCLUSION: For the first time, we confirmed the association of HLA-DRB1*15 with RBC antibody multiresponder status and found HLA-Class II associations for three frequent RBC antibody combinations. Our data support the concept that HLA restriction plays an important role in the response to RBC alloantigens.

A novel HLA-B allele, HLA-B*35:279, identified by sequencing-based typing in a Czech patient.

The identification of a novel HLA-B*35:279 allele in a Czech patient is described. This allele is identical to the B*35:03:01 variant except the G/A nucleotide exchange at position 652 of the HLA-B gene that corresponds to the amino acid substitution from valine to isoleucine in alpha 3 domain of the HLA-B antigen.

Somatic mutation in acute myelogenous leukemia cells imitate novel germline HLA-A allele: a case report.

A somatic mutation of the human leukocyte antigen (HLA)-A gene revealed in tumour cells of acute myelogenous leukemia (AML) is described. A patient with AML and her siblings were routinely typed for HLA in order to find a suitable donor for haematopoietic stem cell transplantation. Sequencing-based typing of the initial patient's sample characterized by high proportion of blasts revealed unknown G/A exchange at position 781 of the HLA-A gene (exon 4) associated with HLA-A*02:01 allele. Importantly, this G781A variant was completely absent in the patient's remission sample obtained after the clearance of blasts. Our results are a reminder that HLA mutations in tumour cells may interfere with routine HLA typing and should always be considered, namely, in patients with haematological malignancies.

A novel HLA-DRB1 allele, HLA-DRB1*13:116, identified by sequencing-based typing in a member of the Czech National Marrow Donor Registry.

We describe the identification of a novel HLA-DRB1 allele, DRB1*13:116, in a member of the Czech National Marrow Donor Registry. The novel allele differs from the known DRB1*13:17 variant by a nucleotide exchange at position 227 (T/A) of the coding HLA-DRB1 sequence, which causes an amino acid substitution (Phe47Tyr) in the HLA-DR beta 1 chain.

MBL2 gene variation affecting serum MBL is associated with prosthetic joint infection in Czech patients after total joint arthroplasty.

Prosthetic joint infection (PJI) is a serious complication of the total joint arthroplasty (TJA). Serum mannose-binding lectin (MBL), a pattern recognition receptor, is involved in antibacterial immune response. This study investigated whether functional variants of the MBL2 gene may be associated with the risk of PJI. MBL2 -550 (H/L, rs11003125), MBL2 -221 (Y/X, rs7096206) and MBL2 +54 (G/A, rs1800450) single nucleotide polymorphisms (SNP) were genotyped in 112 PJI patients and two control groups: 245 patients with aseptic TJA and 196 Czech population controls without TJA. Serum MBL concentration was assessed in PJI patients (n = 92) and aseptic TJA controls (n = 56). The distribution of MBL2 genotypes complied with the Hardy-Weinberg equilibrium in all investigated groups. Importantly, MBL2 -550 L allele (allelic frequency, 0.72) and LL genotype (genotype frequency, 0.51) were more frequent among PJI patients compared to aseptic TJA controls (L allele: 0.63, P = 0.016, P(c) = 0.048; LL genotype: 0.39, P = 0.037, P(c) > 0.05) and to Czech population controls (L allele: 0.61, P = 0.010, P(c) = 0.030; LL genotype: 0.35, P = 0.006, P(c) = 0.018), respectively. Regarding MBL protein, the MBL2 -550 L carriers presented with lower serum MBL concentrations than non-carriers (median; 593 vs 1876 ng/ml; P < 0.01). Similarly, the carriage of MBL2 -221 X and 54 A alleles was associated with lower serum MBL concentrations (P < 0.01). In conclusion, MBL2 -550 genetic variant(s) associated with low serum concentration of MBL protein can increase the risk of PJI.

Interleukin-6 promoter polymorphism and plasma levels in patients with schizophrenia.

Schizophrenia is a severe psychiatric disease with inflammatory component. Several studies indicated the increased blood levels of proinflammatory interleukin-6 cytokine in schizophrenia. However, only limited studies explored the relationship between excess production and genetic variations of this cytokine in schizophrenia, and the results were controversial. Here, we investigated possible association of the interleukin-6 gene (IL6) rs1800795 (-174G/C) polymorphism with schizophrenia and relationship between this polymorphism and interleukin-6 protein (IL-6) blood levels. This polymorphism was found by other researchers to associate with different transcription rates and different plasma levels of IL-6. A total of 208 unrelated Armenians were genotyped by polymerase chain reaction with sequence-specific primers, and IL-6 levels were assessed by enzyme-linked immunosorbent assay. The IL6 rs1800795 alleles and genotypes in both groups were in Hardy-Weinberg (H-W) equilibrium. We found that rs1800795*C allele [38% vs 24%, P = 0.002, odds ratio (OR) = 1.95, 95% confidence interval (CI): 1.18-2.14] and its carriers (62% vs 42%, P = 0.003, OR = 2.28, 95% CI: 1.13-1.94) were more frequent in patients than in controls. IL-6 in patients was 1.5-fold higher than in controls (mean ± SD: 6.41 ± 2.47 pg/ml vs 4.15 ± 1.42 pg/ml, P = 1.9E-19). In both groups, higher IL-6 in rs1800795 GG compared to rs1800795*C allele carriers was observed (GG vs GC + CC, patients: 7.02 ± 2.83 pg/ml vs 5.39 ± 1.2 pg/ml, P = 0.0006; controls: 5.21 ± 1.17 pg/ml vs 3.38 ± 1.03 pg/ml, P = 1.6E-15). In conclusion, we report an association of IL6 rs1800795 and higher IL-6 with schizophrenia. We also conclude that IL6 rs1800795*C allele is linked to increased IL-6 blood levels and may be a risk factor for schizophrenia development at least in Armenian population.

Functional variant ANXA11 R230C: true marker of protection and candidate disease modifier in sarcoidosis.

In the recent genome-wide association study the polymorphisms of annexin A11 (ANXA11) gene were associated with susceptibility to sarcoidosis. Beside the replication of this finding and analysis of local ANXA11 expression in bronchoalveolar lavage cells, we wondered whether 'leading' ANXA11 rs1049550 (R230C) variant might also be related to the clinical manifestation of sarcoidosis. The study included 245 Czech patients with sarcoidosis and 254 healthy control subjects. The frequency of ANXA11(*)T allele was significantly lower in patients with sarcoidosis (35%) compared with controls (42%, P=0.04, odds ratio=0.77). Furthermore, ANXA11(*)T allele was less frequent in patients with the infiltration of lung parenchyma by comparison with those with isolated hilar lymphadenopathy (P=0.01). In line with the previous observation, ANXA11 mRNA expression was not deregulated in sarcoidosis and was independent from rs1049550 variant. In conclusion, ANXA11 rs1049550 single nucleotide polymorphism is the susceptibility marker in sarcoidosis, at least in Caucasians. Its role as a disease modifier should be independently replicated.

T-helper cell type-1 transcription factor T-bet is upregulated in pulmonary sarcoidosis.

Upregulation of genes for interferon (IFN)-γ and CXC chemokine receptor (CXCR)3 expression, two crucial molecules in sarcoid inflammation and granuloma formation, is directly controlled by the T-helper (Th)1 transcription factor T-bet (T-box, expressed in T-cells). However, there is no information on T-bet expression in sarcoidosis or its relationship with "sarcoidosis-associated" genes. Therefore, we investigated expression of T-bet mRNA and, in parallel, a spectrum of genes known to be involved in sarcoidosis pathogenesis. Transcripts were determined in bronchoalveolar lavage (BAL) cells from 62 sarcoidosis patients and 25 controls by quantitative RT-PCR; T-bet protein was localised by immunohistochemistry. Patient's BAL cells expressed higher mRNA T-bet levels than those of controls (mean ± sd fold change 3.64 ± 1.72; p = 0.00006). T-bet mRNA expression did not vary between clinical phenotypes as assessed by chest radiography stage, presence/absence of Löfgren's syndrome, extrapulmonary/pulmonary involvement or progressing/remitting disease (p > 0.05). T-bet mRNA expression correlated with expression of IFN-γ, CC chemokine ligand 5, CXC chemokine ligand (CXC)10, interleukin (IL)-2 receptor/IL-15 receptor ß, CXCR3 and CXCR6 (p < 0.01). T-bet protein was localised to alveolar macrophages and lymphocytes, tissue multinucleated giant cells, macrophages and lymphocytes. In pulmonary sarcoidosis, T-bet upregulation is associated with changes in expression of IFN-γ, CXCR3 and chemokines/receptors involved in the pathogenesis of sarcoidosis, which suggests a role for T-bet in this Th1 disease, including modulation of some sarcoidosis-associated genes.

HLA-C locus and genetic susceptibility to psoriatic arthritis in Romanian population.

We determined the distribution of human leukocyte antigen-C (HLA-C) allelic groups in a cohort of psoriatic arthritis (PsA) patients and a control population of Romanian ethnicity. A nominal association of HLA-C*06 with susceptibility to PsA was observed [P = 0.014, p(corr) > 0.05, odds ratio (OR) 2.1, 95% confidence interval (CI) 1.08-4.46]. When subanalyzing data according to PsA clinical phenotypes, association was noticed between HLA-C*06 and PsA with psoriasis onset before 40 years (p(corr) = 0.013, OR 3.7, 95% CI 1.58-9). This first report from Romania confirmed the association of HLA-C*06 with type I psoriasis in PsA patients. Other study findings, such as the relationship between HLA-C*06 and spondylitis or the protective effect of HLA-C*07 for the polyarthritis clinical phenotype of PsA, are of preliminary character and require verification.

Genetic variants of the inflammatory C-reactive protein and schizophrenia in Armenian population: a pilot study.

C-reactive protein (CRP) is an inflammation marker implicated in the pathogenesis of schizophrenia. To investigate association of the CRP rs1417938, rs1800947, rs1205 variants with susceptibility to schizophrenia 208 unrelated Armenians (103 patients and 105 healthy controls) were genotyped. In this pilot study, none of studied variants was associated with schizophrenia.

MCP-1 -2518 A/G gene polymorphism is associated with blood pressure in ischemic heart disease asymptomatic subjects.

Monocyte chemoattractant protein-1 (MCP-1), one of the key inflammatory chemokines, plays an important role in the initiation of atherosclerosis, and represents a risk for coronary artery disease and myocardial infarction. A recent animal study showed that MCP-1 gene might be a candidate gene for salt-sensitive hypertension in Dahl salt sensitive rats. This effect has not been yet studied in asymptomatic humans. We tested the MCP-1 -2518 A/G single nucleotide polymorphism (SNP) in 66 hypertensive ischemic heart disease asymptomatic subjects. Inflammatory markers, classic risk factors and absolute cardiovascular risk (SCORE system) were also investigated in these subjects. Our results showed that both, systolic and diastolic values of blood pressure were associated with MCP-1 -2518 A/G SNP at the level of both, genotype and allele frequencies. Subjects with mutant G allele had higher levels of both values of blood pressure, systolic (p = 0.035) and diastolic (p = 0.040) than subjects with allele A. Statistically significantly higher levels of both values of blood pressure, systolic (p = 0.037) and diastolic (p = 0.021) were found also in IHD asymptomatic subjects with AG and GG genotypes. Subjects with AG and GG genotypes had also an increased absolute cardiovascular risk (1.62% vs 3.17%; p = 0.004) and an increasing trend for elevated plasma level of high-sensitive CRP (2.858 vs 2.062 mg/l; p = 0.076). We did not find any significant correlation between the serum level of MCP-1 and blood pressure. To our best knowledge, this is the first study concerning the association between MCP-1 polymorphism and arterial blood pressure in IHD asymptomatic subjects. These results indicate that the expression of MCP-1 may be increased before the onset of hypertension but further observations from larger cohorts are needed to confirm this finding (Tab. 6, Ref. 41).

Protein levels of CC chemokine ligand (CCL)15, CCL16 and macrophage stimulating protein in patients with sarcoidosis.

The objective of this study was to assess protein levels for candidate cytokines, chemokines, growth factors, matrix metalloproteinases and their inhibitors in bronchoalveolar lavage fluid (BALF) in patients with polar forms of pulmonary sarcoidosis, i.e. Löfgren's syndrome (LS) and more advanced chest X-ray (CXR) stage III disease. Twenty-four inflammatory molecules were analysed in unconcentrated BALF samples from 10 sarcoidosis patients with CXR stage III and 10 patients with LS by semiquantitative protein array. Four novel molecules [CC chemokine ligand (CCL)15, CCL16, macrophage migration inhibitory factor (MIF) and macrophage stimulating protein (MSP)], detected for the first time in association with sarcoidosis, were then quantified by enzyme-linked immunosorbent assay in a second cohort of 68 sarcoidosis patients and 17 control subjects. The protein levels of CCL15, CCL16, CCL24, CXCL8, CXCL9, CXCL10, interleukin-16, MIF, MSP and matrix metallopeptidase 1 were increased in CXR stage III patients when compared with patients with LS. CCL15 and MSP up-regulation in CXR stage III patients in comparison with LS patients and controls was confirmed by enzyme-linked immunosorbent assay. Moreover, MSP was associated with treatment requirement (P = 0.001) and CCL15 was elevated in patients with disease progression at 2-year follow-up (P = 0.016). CCL16 levels were increased in sarcoidosis versus controls (P < 0.05), but no difference was observed between patient subgroups. MIF up-regulation was not confirmed in a larger patient group. In conclusion, chemokines CCL15, CCL16 and MSP were found elevated for the first time in BALF from sarcoidosis patients; our results showed that CCL15 and MSP may affect disease course.

MCP-1 and CCR2 gene polymorphisms in Czech patients with allergic disorders.

Several lines of evidence suggest that chemokines play an important role in asthma and allergy. We analysed polymorphisms at -2518A/G and -2076A/T of MCP-1 and V64I of CCR2 gene in healthy subjects (n = 306) and allergic patients (n = 332). Allele and genotype frequencies did not differ significantly between groups. Nevertheless, MCP-1 variants were associated with allergen sensitization. The results suggest that MCP-1, but not CCR2 gene variants, may participate in the pathogenesis of allergic phenotypes at least in the Caucasian population.

The MCP-1 -2518 (A/G) single nucleotide polymorphism is associated with ischemic heart disease and myocardial infarction in men in the Slovak population.

We investigated the MCP-1 -2518 (A/G) single nucleotide polymorphism (SNP) in Slovak cohort of patients with ischemic heart disease (IHD). Our study comprised 270 patients with IHD, out of them 92 with myocardial infarction (MI). We found that the frequencies of the mutant GG genotype in Slovak patients with IHD (10.7%; p=0.019) and MI (12.0%; p=0.046) were significantly higher than those in the control subjects (5.8%). After subdividing the groups according to the sex, statistically significant difference was found only in men (IHD: p=0.013, MI: p=0.009). We also found a higher rate of GG homozygous genotype in patients with early (< or =50 years of age) MI (18.4%; p=0.004)--statistically significant again only in men (23.1%; p=0.002). The frequencies of G alleles in IHD male patients (30.3%, p=0.046) and in early MI male patients (38.5%, p=0.019) were also statistically significantly higher than in control group. Our results confirm that IHD and MI are linked to MCP-1 -2518 (A/G) single nucleotide polymorphism (Tab. 4, Ref. 34). Full Text (Free, PDF) www.bmj.sk.

The CR1 C5507G polymorphism is not involved in susceptibility to idiopathic pulmonary fibrosis in two European populations.

Idiopathic pulmonary fibrosis (IPF), a severe lung disease with unknown aetiology, is thought to have an important genetic component. Single nucleotide polymorphism, C5507G, of the complement receptor 1 (CR1) gene, which affects the number of CR1 molecules on erythrocytes, has been associated with susceptibility to IPF in a single European population. To replicate this finding, 53 Czech IPF patients with 203 Czech healthy control subjects and 70 English IPF patients with 149 English controls were investigated. In both populations, there were no significant differences in distribution of CR1 C5507G variants between IPF patients and their appropriate control groups. In conclusion, the association of the CR1 C5507G polymorphism with susceptibility to IPF was not reproducible in Czech and English populations.

Association of IL-6 gene polymorphism with the outcome of allogeneic haematopoietic stem cell transplantation in Czech patients.

Interleukin-6 (IL-6) is an important pro-inflammatory mediator implicated in immune-mediated complications of allogeneic haematopoietic stem cell transplantation (aHSCT). In accord with previous reports, this preliminary study on 56 donor-recipient pairs revealed IL-6-174 single nucleotide polymorphisms as a risk factor for the development of acute graft-versus-host disease and decreased survival after aHSCT.

Bone remodeling, particle disease and individual susceptibility to periprosthetic osteolysis.

Bone remodeling is a tightly coupled process consisting of repetitive cycles of bone resorption and formation. Both processes are governed by mechanical signals, which operate in conjunction with local and systemic factors in a discrete anatomic structure designated a basic multicellular unit (BMU). The microenvironment around total joint arthroplasty is a dynamic and complex milieu influenced by the chemical and physical stimuli associated with servicing the prosthesis. A key factor limiting the longevity of the prosthesis is polyethylene wear, which induces particle disease, and this may lead to increased and prolonged activity of BMUs resulting in periprosthetic osteolysis. Several pathways regulating BMU function have been reported in the past, including RANKL/RANK/OPG/TRAF6, TNF-alpha/TNFR/TRAF1, and IL-6/CD126/JAK/STAT. Moreover, the expression and functional activity of all these molecules can be affected by variations in their genes. These may explain the differences in severity of bone defects or prosthetic failure between patients with similar wear rates and the same prosthesis. Simultaneously, this data strongly support the theory of individual susceptibility to prosthetic failure.

[Involvement of immunogenetic factors in the development of periprosthetic osteolysis]. / Podíl imunogenetických faktoru na vzniku a rozvoji periprotetické osteolýzy.

Aseptic loosening and osteolysis are the most frequent causes of total hip or total knee arthroplasty failure. Osteolysis is induced predominantly by polyethylene particles that are produced by adhesive wear of the prosthesis. The particles trigger a complex host's reaction varying in intensity even in response to the same number of particles. These differences indicate that individual predisposition may have an important role in the pathogenesis of osteolysis. The major key mediators of wear-induced osteolysis include the cytokines RANKL, TNF-a, IL-1, IL-6 and IL-8. The inter-individual differences in the extent of bone destruction may therefore be related to variation in the amount and/or activity of these cytokines based on their gene polymorphism. Our pilot study suggests an association of some variants of the cytokine genes (e.g., IL1A-889) with a predisposition to development of severe osteolysis. If this assumption is confirmed by future investigations, this approach can facilitate the pre-operative identification of patients at risk of the development of severe periprosthetic osteolysis and premature failure of the implant.