Protective effect of HLA-DQB1 alleles against alloimmunization in patients with sickle cell disease

BackgroundAlloimmunization or the development of alloantibodies to Red Blood Cell (RBC) antigens is considered one of the major complications after RBC transfusions in patients with sickle cell disease (SCD) and can lead to both acute and delayed hemolytic reactions. It has been suggested that polymorphisms in HLA genes, may play a role in alloimmunization. We conducted a retrospective study analyzing the influence of HLA-DRB1 and DQB1 genetic diversity on RBC-alloimmunization.Study designTwo-hundred four multi-transfused SCD patients with and without RBC-alloimmunization were typed at low/medium resolution by PCR-SSO, using IMGT–HLA Database. HLA-DRB1 and DQB1 allele frequencies were analyzed using logistic regression models, and global p-value was calculated using multiple logistic regression.ResultsWhile only trends towards associations between HLA-DR diversity and alloimmunization were observed, analysis of HLA-DQ showed that HLA-DQ2 (p = 0.02), -DQ3 (p = 0.02) and -DQ5 (p = 0.01) alleles were significantly higher in non-alloimmunized patients, likely behaving as protective alleles. In addition, multiple logistic regression analysis showed both HLA-DQ2/6 (p = 0.01) and HLA-DQ5/5 (p = 0.03) combinations constitute additional predictor of protective status.ConclusionOur data suggest that particular HLA-DQ alleles influence the clinical course of RBC transfusion in patients with SCD, which could pave the way towards predictive strategies.     

Association of HLA class II (-DRB1,-DQB1,-DPB1) alleles and haplotypes on susceptibility to aplastic anemia in northern Chinese Han

The Human Leukocyte Antigen (HLA) genes, playing key roles in mediating the immune response, especially HLA class II alleles were suggested to play a role in the activation of autoreactive T-cells in aplastic anemia (AA). Previous studies in different ethnic groups have indicated that some of HLA-A,-B,-DRB1 alleles had a protective or susceptive association with the prevalence, pathogenesis and development of AA. HLA class II genes, especially HLA-DQB1 and -DPB1 alleles or haplotypes at high-resolution level associated with AA have not been fully identified in northern Chinese Han populations. The aim of this study was to identify association of the variations in HLA class II region with AA in northern Chinese Han population. A recent case-control study, including 96 AA patients and 824 healthy controls was performed. The high-resolution HLA genotyping was conducted by PCR-SBT, -SSO and NGS-ION S5^TM platform. Based on genotypic data of the three loci, haplotype estimation was carried out. HLA-DRB1*15:01 (Pc = 2.87 × 10^-3; OR = 2.11, 95% CI = 1.45–3.07) and HLA-DQB1*06:02 (Pc = 1.86 × 10^-2; OR = 2.01, 95% CI = 1.32–3.06) were the risk and predisposition alleles to AA in northern Chinese Han after considering multiple testing. Moreover, the HLA-DRB1*15:01-DQB1*06:02 (Pc = 4.90 × 10^-3; OR = 2.09, 95% CI = 1.37–3.19) and HLA-DRB1*14:05-DQB1*05:03 (Pc = 2.65 × 10^-2; OR = 2.82, 95%CI = 1.45–5.50) haplotypes had direct strong relevance to AA and were the susceptible haplotypes. HLA-DPB1 alleles and 23 polymorphic amino acid residues spanning exon 2 ~ 4 of DPβ1 molecules have showed no statistically significant associations between AA and controls. The present findings establish a novel link between inherited HLA-DRB1,-DQB1,-DPB1 risk alleles and haplotypes in northern Chinese Han with AA, and open new avenues for development of targeted therapies to prevent or redirect immunopathology in AA.     

Prevalence and risk factors of antibodies to human leukocyte antigens in haploidentical stem cell transplantation candidates: A multi-center study

We investigated the prevalence of and risk factors for antibodies to HLA in 1663 haploidentical transplant candidates. Among these cases, 349 (21.0%) showed positive panel-reactive antibody (PRA) either for class I or class II HLA. Multivariate analysis showed the following: i) risk factors associated with the prevalence of PRA either for class I or class II HLA were female gender (P?=?0.018), prior transfusions (P?<?0.001) or pregnancy (P?<?0.001), and cases with MDS (P?=?0.018); compared to other patients, subjects with ALL had a lower prevalence of class I antibodies (P?=?0.017); and ii) risk factors associated with the prevalence of PRA both for class I and class II HLA were female gender (P?=?0.014), prior transfusions (P?=?0.003), previous pregnancy (P?<?0.001), and diagnosis with MDS (P?=?0.035). The percentages of antibodies against different antigens coded by the different HLA loci, including HLA-A, -B, -C, -DP, -DQ, and -DR, among all cases were 15.6%, 17.3%, 10.5%, 5.6%, 8.5%, and 9.7%, respectively. Risk factors associated with specific antibodies against HLA-A, -B, -C, -DP, -DQ, and -DR were female gender, prior transfusion, previous pregnancy, and underlying disease. Our findings suggest that gender, prior pregnancy, transfusion and underlying diseases are risk factors for HLA sensitization, which could guide HLA antibody monitor and donor selection.     

Haplotype analysis of HLA‐A, ‐B antigens and ‐DRB1 alleles in south Indian HIV‐1‐infected patients with and without pulmonary tuberculosis

We have shown earlier the association of human leucocyte antigen (HLA)‐A11 with resistance and HLA‐B40 and ‐DR2 with susceptibility to HIV and HIV‐TB. In the present study, we have attempted to find out the HLA‐DR2 subtypes and the possible HLA‐A/‐B/‐DRB1 haplotype combinations that are associated with susceptibility or resistance to HIV and HIV with pulmonary tuberculosis (HIV+PTB+). HLA‐DR2 subtyping was carried out by polymerase chain reaction‐based sequence‐specific oligonucleotide probe method. Overrepresentation of HLA‐DRB1*1501 in HIV‐positive PTB‐negative (HIV+PTB–) patients (P = 0.004, P_c = 0.06) and ‐DRB1*1502 in HIV‐positive PTB‐positive (HIV+PTB+) patients (P = 0.019) was observed as compared to healthy controls. Haplotype analysis revealed an increased frequency of HLA‐A2‐DRB1*1501 haplotype in HIV+PTB– patients (P = 0.008) and HLA‐A2‐DRB1*1502 among HIV+PTB+ patients (P = 0.01) compared to healthy controls. The haplotypes B40‐DRB1*1501 and B40‐DRB1*04 were found to be moderately increased in HIV+PTB– and HIV+PTB+ patients (P < 0.05). The study suggests that HLA‐A2‐DRB1*1501 haplotype may be associated with HIV infection while HLA‐A2‐DRB1*1502 haplotype might be associated with susceptibility to PTB in HIV patients. Moreover, HLA‐B40‐DRB1*1501 and HLA‐B40‐DRB1*04 haplotypes may be associated with susceptibility to HIV infection and to PTB in HIV patients.     

Cytokine dependent hematopoietic cell linker (CLNK) is highly elevated in blood transfusion dependent beta-thalassemia major patients

BackgroundTransfusion-dependent β-thalassemia (TDT) is a severe form of thalassemia caused by mutations in the β-globin gene, resulting in partial or complete deficiency of β-globin chains. This deficiency results in oxidative stress, dyserythropoiesis, and chronic anemia. Cytokine-dependent hematopoietic cell linker (CLNK) belongs to adaptor proteins that have the capacity to interact with multiple signalling proteins and function in the organisation of the molecular components required for signal transduction.ObjectivesThis is the first study which measured serum CLNK in TDT patients and examines the correlation between CLNK and iron overload biomarkers.Patients and methodsSixty children with TDT and 30 normal children (aged 3–12 years old) participated in the present study. The patients were on blood transfusion as a part of their treatment regimen. Serum C-reactive protein was negative in all samples.ResultsThe results showed significantly higher (P < 0.001) serum CLNK levels in TDT patients as compared with controls. The TDT diagnosis explained 19.4% of the variance in CLNK levels. The increased levels of CLNK were significantly associated with indicants of iron overload, namely increased ferritin levels.ConclusionsIncreased CLNK levels in TDT may be explained by reciprocal effects between immune signalling and immature erythrocytes, which release soluble receptors and signalling molecules, including CLNK, in the blood.     

Human leucocyte antigen (HLA) expression of primary trophoblast cells and placental cell lines,determined using single antigen beads to characterize allotype specificities of anti-HLA antibodies

Human trophoblast cells express an unusual repertoire of human leucocyte antigen (HLA) molecules which has been difficult to define. Close homology between and extreme polymorphism at the classical HLA class-I (HLA-I) loci has made it difficult to generate locus-specific monoclonal antibodies (mAbs). The problem of defining an antibody''s reactivity against the thousands of existing HLA-I allotypes has often made it impossible to determine the HLA bound by a mAb in biological samples from a normal outbred population. Here we have used commercially available beads coated with individual HLA-I to characterize experimentally the reactivity of nine mAb against 96 common HLA-I allotypes. In conjunction with donor HLA-I genotyping, we could then define the specific HLA molecules bound by these antibodies in normal individuals. We used this approach to analyse the HLA expression of primary trophoblast cells from normal pregnancies; the choriocarcinoma cells JEG-3 and JAR; and the placental cell lines HTR-8/SVneo, Swan-71 and TEV-1. We confirm that primary villous trophoblast cells are HLA null whereas extravillous trophoblast cells express HLA-C, HLA-G and HLA-E, but not HLA-A, HLA-B or HLA-DR molecules in normal pregnancy. Tumour-derived JEG-3 and JAR cells reflect extravillous and villous trophoblast HLA phenotypes, respectively, but the HLA repertoire of the in vitro derived placental cell lines is not representative of either in vivo trophoblast phenotype. This study raises questions regarding the validity of using the placental cell lines that are currently available as model systems for immunological interactions between fetal trophoblast and maternal leucocytes bearing receptors for HLA molecules.     

The HLA‐DRB, ‐DQB polymorphism and anti‐insulin antibody response in Slovenian patients with type 1 diabetes

A combination of specific HLA class II antigens and the presence of type 1 diabetes (T1D)‐related antibodies has a high positive predictive value for T1D but low sensitivity. The aim of the present study was to determine the frequencies of HLA‐DRB‐DQB deduced haplotypes associated with susceptibility and protection in Slovenian patients with established T1D, to evaluate the relationship between the HLA‐DRB1‐QBP‐DQB1 haplotypes and the presence of insulin autoantibodies (IAA) and glutamic acid decarboxylase antibodies (GADA), and to access the possible impact of polymorphic QBP promoters on this relationship. A cohort of 135 patients with T1D (age 17.5 ± 7.0 years, duration of T1D 9.14 ± 6.3 years) was investigated. HLA‐DRB1 and DQB1 alleles were typed using the polymerase chain reaction (PCR)–reverse line blot method. QBP promoter region alleles were determined using PCR–sequence‐specific oligonucleotide hybridization (SSO) and PCR–sequence‐specific primers (SSP). IAA and GADA antibodies were determined by enzyme‐linked immunosorbent assay (ELISA). The chi‐square test with Yates’ correction was used for statistical analysis. Deduced haplotypes DRB1*0301‐DQB1*0201 (P = 0.0001, OR = 3.4), DRB1*0401‐DQB1*0302 (P = 0.0001, OR = 29.8), and DRB1*0402‐DQB1*0302 (P = 0.008, OR = 4.7) were significantly more common, and DRB1*1501‐DQB1*0602 (P = 0.0001, OR = 0.03) significantly less common in the investigated cohort than in a Slovenian control group. The highest risk and the strongest protective HLA‐DR‐DQ haplotypes found in Slovenian patients with T1D did not differ from those found in other Caucasian populations. While the DRB1*0301‐QBP2.1‐DQB1*0201 haplotype, where QBP2.1 did not help to further distinguish DQB1*0201‐possessing haplotypes in IAA‐positive and IAA‐negative patients, was strongly associated with the presence of IAA, the DRB1*0101‐QBP5.12‐DQB1*0501 haplotype, although not protective compared to the control population, was associated with an absence of IAA in the investigated cohort. It is suggested that there may be a combined influence of the QBP5.12 promoter and the DQB1*0501 functional molecule on reduced IAA production.     

Distribution of HLA class I and II genes in ankylosing spondylitis patients from Morocco

ObjectivesIn Morocco, the patients affected by ankylosing spondylitis (AS) presents a high frequency of coxitis. Our study reports, for the first time, the polymorphism of Human Leukocyte Antigen (HLA) class I and class II molecules in the Moroccan patients.MethodsForty-six patients diagnosed with an AS and coxitis were compared to a group of 183 healthy controls matched by age, sex and ethnic origin. The HLA typing was performed using microlymphocytotoxicity for the class I (-A, -B) and PCR-SSP for the class II (-DR, -DQ).ResultsWe found a significant increase of the HLA-B27 antigen frequency (P < 0.0001, RR = 20.9) in AS patients (29.3%) compared to the controls (3.2%) and a significant decrease in the frequency of HLA-B12 and HLA-B18 antigens. Examination of HLA class II distribution shows a significant increase of the HLA-DRB1*11 allele frequency in patients (P < 0.0001). Concerning HLA-DQB1* alleles, no significant difference between patients and controls was appreciable.ConclusionsThe HLA-B27 antigen is involved in the predisposition to the AS with coxitis in the Moroccan population. However, the low frequency observed in our population suggests the existence of other genetic and/or environmental factors. Other HLA genes seem to confer a predisposing effect (DRB*11) or a protective effect (B12 and B18) against the disease.     

Associations of HLA class II alleles with pulmonary tuberculosis in Thais

Tuberculosis is an important infectious disease in Thailand. Susceptibility to tuberculosis is influenced not only by the environment but also by host genetic factors. In this study, we investigated HLA alleles in 82 patients with tuberculosis from Bangkok and in 160 normal controls. HLA‐DRB1, DQA1 and DQB1 genotyping was performed by the PCR‐SSO method. The frequency of HLA‐DQB1*0502 was increased in tuberculosis patients compared to the normal controls (P = 0.01, OR = 2.06). In contrast, the frequencies of DQA1*0601 and DQB1*0301 were decreased in tuberculosis patients compared to the controls (P = 0.02 and P = 0.01, respect­ively). Our results suggest that HLA‐DQB1*0502 may be involved in the development of pulmonary tuberculosis, whereas HLA‐DQA1*0601 and DQB1*0301 may be associated with protection against tuberculosis.     

Nonclassical human leukocyte antigen (HLA-G,HLA-E,and HLA-F) in coronary artery disease

AimsSeveral evidences suggest the association between the evolution of coronary artery disease (CAD) and the development of coronary syndrome that is often associated with disrupted plaque and partial or complete thrombosis of the related artery. Because of the inflammatory nature of CAD, we investigated the human leukocyte antigen (HLA)-G, HLA-E, and HLA-F genetic polymorphisms within CAD patients and evaluated their potential association with this disease in Tunisian population.MethodsDifferent polymorphisms in HLA-G (14-bp Insertion/Deletion, +3142C/G), HLA-E (HLA-E*01:01/01:03 A/G), HLA-F (HLA-F*01:02 T/C, 01:03 C/T, 01:04 A/C) genes were typed using different laboratory techniques in a cohort of 89 CAD patients and 84 controls.ResultsA significant association was reported between the HLA-G +3142 G allele (OR = 1.64, 95% CI = 1.05–2.56, p = 0.02) and increased risk of CAD. No association was found for the other studied polymorphisms. When we considered the haplotypes, we found TDELCA and TDELGG haplotypes associated to CAD with p = 0.008 and p = 0.030, respectively, suggesting the potential interaction between HLA-G and HLA-E genes.ConclusionsOur findings indicated that the HLA-G +3142C/G polymorphism and TDELCA and TDELGG haplotypes can harbour a reliable diagnosis value for the risk of CAD development suggesting that HLA-G, -E and -F molecules might be involved in the pathogenesis of the disease. However, further studies are necessary to confirm our results.     

High birth weight is associated with human leukocyte antigen (HLA) DRB1*13 in full‐term infants

In cord blood banking, substantial amounts of data on infants and cord blood are gathered at high cost, including birth weights and human leukocyte antigen (HLA) genotypes. As certain HLA alleles have been associated with protective host responses, it is possible that an HLA allele, or another factor linked to it, might even affect normal intrauterine growth. We explored cord blood bank data (n = 1381 infants) to elucidate whether there is an association between birth weight and HLA class II (DRB1) alleles. HLA DRB1 data were available from 1263 infants. We observed an association between birth weight and HLA DRB1*13, which was over‐represented among full‐term infants with the highest birth weights. The association remained when the birth weight was corrected for varying gestational age (relative birth weight) according to gender (P = 0.015). After correction of the P‐value for multiple comparisons, the association was not statistically significant. However, when the birth weights of all infants were analysed for the effect of DRB1*13, infants positive for HLA DRB1*13 (n = 319) were found to have higher birth weights than infants negative for this allele (n = 944; median 3690 g vs. 3650 g, respectively; P = 0.044). Although the difference in median birth weight was only 40 g, it may be considered significant because it appeared after segregation of the infants into two groups according to the single HLA class II allele group earlier associated with protection against, for example, childhood type 1 diabetes and certain infectious diseases. The present finding may thus suggest identification of a new factor affecting normal intrauterine growth.     

Impact on Outcomes of Human Leukocyte Antigen Matching by Allele-Level Typing in Adults with Acute Myeloid Leukemia Undergoing Umbilical Cord Blood Transplantation

This retrospective study analyzed the impact of directional donor-recipient human leukocyte antigen (HLA) disparity using allele-level typing at HLA-A, -B, -C, and -DRB1 in 79 adults with acute myeloid leukemia (AML) who received single-unit umbilical cord blood (UCB) transplant at a single institution. With extended high-resolution HLA typing, the donor-recipient compatibility ranged from 2/8 to 8/8. HLA disparity showed no negative impact on nonrelapse mortality (NRM), graft-versus-host (GVH) disease or engraftment. Considering disparities in the GVH direction, the 5-year cumulative incidence of relapse was 44% and 22% for patients receiving an UCB unit matched ≥ 6/8 and < 6/8, respectively (P = .04). In multivariable analysis, a higher HLA disparity in the GVH direction using extended high-resolution typing (Risk ratio [RR] 2.8; 95% confidence interval [CI], 1.5 to 5.1; P = .0009) and first complete remission at time of transplantation (RR 2.1; 95% CI, 1.2 to 3.8; P = .01) were the only variables significantly associated with an improved disease-free survival. In conclusion, we found that in adults with AML undergoing single-unit UCBT, an increased number of HLA disparities at allele-level typing improved disease-free survival by decreasing the relapse rate without a negative effect on NRM.     

HLA‐DRB1 gene polymorphisms and its associations with rheumatoid arthritis in Chinese Han women of Shaanxi province,northwest of China

Rheumatoid arthritis (RA) is a common chronic autoimmune disease characterized by symmetric polyarthritis. This study was designed to investigate the associations between HLA‐DRB1 gene polymorphisms and RA in the Chinese Han population of Shaanxi province, northwest of China. In total, we identified 31 high‐resolution HLA‐DRB1 alleles in 109 patients with RA. Compared with the controls, the AF of HLA‐DRB1*04:05 (P = 0.000, Pc = 0.007, OR = 3.462, 95%CI: 1.749–6.852) was significantly higher in patients with RA. In addition, the patients with RA had higher allele frequency (AF) of the HLA‐DRB1*04:03 (P = 0.030, Pc = NS, OR = 4.737, 95%CI: 1.012–22.180); DRB1*04:06 (P = 0.018, Pc = NS, OR = 5.288, 95%CI: 1.145–24.422) and the shared epitope (SE) alleles (P = 0.004, Pc = NS, OR = 2.166, 95%CI: 1.279–3.667), respectively. Moreover, positive possibilities of RF and anti‐CCP were significant higher in SE‐positive patients compared to SR‐negative patients (OR = 4.787, 95%CI: 1.101–20.824; OR = 3.775, 95%CI: 1.106–12.876, respectively). Our results indicated that HLA‐DRB1*04:05, *04:03, *04:06 and SE alleles might be susceptibility allele for RA in Chinese Han population of Shaanxi province, northwest of China.     

Alpha tryptase allele of Tryptase 1 (TPSAB1) gene associated with Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS) in Vietnam and Philippines

We previously reported, significantly higher levels of Chymase and Tryptase in early stage plasma of DSS patients prior to the occurrence of shock suggesting a possible role of mast cells in dengue pathogenesis. To further investigate, we analyzed CMA1 promoter SNP (rs1800875) and TPSAB1 gene alleles, which encode the Human Chymase and α- and β- tryptase 1 enzymes respectively, for susceptibility to Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS) in patients from hospitals in Vietnam (Ho Chi Minh City and Vinh Long) and the Philippines. While the CMA1 promoter SNP (rs1800875) was not associated with DHF/DSS, the homozygous form of α-tryptase allele was associated with DSS patients in Vinh Long and the Philippines (OR = 3.52, p < 0.0001; OR = 3.37, p < 0.0001, respectively) and with DHF in Ho Chi Minh City (OR = 2.54, p = 0.0084). Also, a statistically significant association was observed when DHF and DSS were combined in Vinh Long (OR = 1.5, p = 0.034) and the Philippines (OR = 2.36, p = 0.0004); in Ho Chi Minh City when DHF and DSS were combine an association was observed, but it was not statistically significant (OR = 1.5, p = 0.0505). Therefore, the α-tryptase might have a possible effect on the susceptibility to severe form of Dengue infection.     

Multiple transfusions for sickle cell disease in the Democratic Republic of Congo: The importance of the hepatitis C virus

Background and objectivesImprovement of transfusion security in sub-Saharan countries requires the determination of priorities taking into account the specific context.Patients and methodsOne hundred and forty patients with sickle cell disease (SCD) from one clinical centre for SCD in Kisangani, DRC were tested for HBsAg, anti-HIV antibodies, anti-HCV antibodies and for alloantibodies against red blood cells and human leucocyte antigens (HLA).ResultsThirteen patients had not been transfused and were free of HBV, HIV or HCV infection. HBV, HIV and HCV infections were detected in 2/127 (1.6%), 1/127 (0.9%) and 10/127 (7.9%) transfused patients, respectively. All ten cases of HCV infection were associated with patients who had transfusions prior to the introduction of HCV testing in 2004 (P = 0.043). Red blood cells and HLA alloantibodies were detected in 13/127 (10%) and 2/127 (1.6%), respectively.ConclusionHCV testing should be a priority. The rhesus (Rh) phenotype, mainly the RhD antigen and the Kell antigen should be assessed in SCD patients. Further extended phenotyping and deleucocytation should not be considered as priorities.     

The impact of killer cell immunoglobulin-like receptor (KIR) genes and human leukocyte antigen (HLA) class I ligands on predisposition or protection against prostate cancer

Natural killer (NK) cell development largely depends on killer cell immunoglobulin-like receptors (KIRs) and human leukocyte antigen (HLA) class I ligands. In the current study, we investigated the role of KIR genes, HLA ligands, and KIR-HLA combinations in vulnerability or protection against prostate cancer (PC). To analyze the frequency of 16 KIR genes and 5 HLA ligands, polymerase chain reaction with sequence-specific primers (PCR-SSP) was conducted in 150 PC patients and 200 healthy controls (CNs). KIR2DL5 (p = 0.0346, OR = 0.606, CI = 0.3916–0.9336), KIR2DS5 (p = 0.0227, OR = 0.587, CI = 0.3793–0.9139), HLA-B Bw4^Thr80 (p = 0.0401, OR = 0.3552, CI = 0.1466–0.9059), HLA Bw4 (p = 0.0190, OR = 0.4744, CI = 0.2656–0.8521), and T4 gene cluster (including KIR2DS5-2DL5-3DS1-2DS1 genes) (p = 0.0194, OR = 0.5575, CI = 0.3449–0.8938) had a lower frequency in the PC patients compared to the control group. Moreover, a lower frequency of the genotypes contacting activating KIR (aKIR) > inhibitory KIR (iKIR) (p = 0.0298, OR = 0.5291, CI = 0.3056–0.9174) and iKIR + HLA < aKIR + HLA (p = 0.0183, OR = 0.2197, CI = 0.0672–0.7001) in PC patients compared to the CNs implies a protective role for aKIR genes. In the case of KIR-HLA interactions, we detected a significant association between KIR3DS1⁺ + HLA-A Bw4⁺ (p = 0.0113, OR = 0.5093, CI = 0.3124–0.8416) and KIR3DL1^? + HLA-A Bw4⁺ (p = 0.0306, OR = 0.1153, CI = 0.0106–0.6537) combinations and resistance to prostate cancer. In contrast, the presence of KIR3DL1 in the absence of HLA-A Bw4 (p = 0.0040, OR = 2.00, CI = 1.264–3.111), HLA Bw4 (p = 0.0296, OR = 2.066, CI = 1.094–3.906), and HLA-Bw4^Thr80 (p = 0.0071, OR = 2.505, CI = 1.319–4.703) genes probably predisposes to prostate cancer. Carrying the CxT4 genotype in PC patients was positively associated with lower tumor grades (Gleason score ≤ 6) (p = 0.0331, OR = 3.290, and CI = 1.181–8.395). Altogether, our data suggest a protective role for aKIRs, HLA-B Bw4^Thr80, and HLA Bw4 ligands as well as a predisposing role for certain KIR-HLA combinations in prostate cancer. The findings of this study offer new insight into the population's risk assessment for prostate cancer in men. Additionally, predicting immunotherapy response based on KIR-HLA combinations aids in implementing the most effective therapeutic approach in the early stages of the disease.     

Prevalence of human leukocyte antigen (HLA) DRB1 alleles in Kuwaiti children with juvenile rheumatoid arthritis

The prevalence of human leukocyte antigen (HLA) DR alleles has been determined in 69 Kuwaiti Arab children with juvenile rheumatoid arthritis (JRA) and compared to that in 212 ethnically matched normal healthy controls using a PCR–sequence specific primers (PCR‐SSP) method. A very high incidence of DR3 was detected in JRA patients compared to the controls (P < 0.0001, RR = 2.235). The high incidence of HLA‐DR3 in JRA patients was accounted for mainly by an excess of DRB1*0307 (P < 0.05, RR = 3.072) and DRB1*0308 (P < 0.009, RR = 2.663) compared to the controls. Moreover, DR3 was more prevalent when patients with ANA‐positive JRA were analysed separately; 73% compared to 58% for the whole JRA patient group. The frequency of DR1 was also higher in the JRA group compared to controls (P = 0.019, RR = 3.585). Although the incidence of some alleles was higher in the control group (DR13 and DR7), none reached a statistically significant level. All the patients with iridocyclitis had either a DR1 or DR3 allele, except for one child. The frequency of DRB1*03 was found to be much higher in the polyarticular subtype of Kuwaiti JRA cases compared to the oligoarticular subgroup and the controls. Also, a non‐significant increase in the frequency of the DRB1*04, *11 and *15 alleles was detected in the polyarticular subtype of the Kuwaiti JRA cases compared to the controls.     

HLA-DRB1*04 may predict the severity of disease in a group of Iranian COVID-19 patients

Human leukocyte antigen (HLA) genes with extreme diversity can make a contribution for individual variations to the immune response against SARS-COV-2 infection. This study aimed to explore the distributions of HLA class II alleles frequencies and their relations with disease severity in a group of Iranian COVID-19 patients. This prospective and case-control study was conducted on 144 COVID-19 patients including 46 cases with moderate form, 54 cases with severe and 44 cases with critical disease. HLA-DRB1 and -DQB1 allele families were determined by PCR-SSP method and compared between three groups of the patients and in comparison to 153 ethnic-matched healthy controls. The patients group showed lower frequencies of HLA-DRB1*15 (OR = 0.57, P = 0.06), DRB1*15 ~ DQB1*05 haplotype (P = 0.04) and DRB1*15/DRB1*04 genotype (P = 0.04) in compare with healthy controls. Moderate COVID-19 patients had higher frequencies of HLA-DRB1*04 (P = 0.03), HLA-DRB1*10 (P = 0.05) and DRB1*04/DRB1*11 genotype (P = 0.01). Also, a higher significantly frequency of HLA-DRB1*03 allele group was observed in the critical patients versus controls (P = 0.01). Multiple logistic regression analysis revealed that the presence of DRB1*04 allele group was negatively associated with development of severe and critical disease (OR: 0.289, P = 0.005). Our results indicate a possible contribution of some HLA class II alleles in disease severity and clinical features of COVID-19 disease.     

The genetic contribution of HLA‐DRB5*01:01 to systemic lupus erythematosus in Thailand

Human leucocyte antigen (HLA) study in patients with systemic lupus erythematosus (SLE) has been investigated in various countries, but the results are still inconclusive. This study was performed to investigate the association between HLA‐DR and SLE in patients in northern Thailand. HLA‐DR subtyping was performed in 70 patients with SLE and 99 normal healthy controls living in northern Thailand using the INNO‐LiPA HLA‐DR Decoder kit (Innogenetics) and MICRO SSP HLA DNA Typing kit (One Lambda) for reconfirmation. The allele frequency (AF) of DRB5*01:01 in SLE was significantly higher than in the controls [25.7% vs. 14.6%, P = 0.012, Pc = 0.048, OR = 2.02 (95%CI = 1.17–3.48)]. The AF of DRB1*15:01 and DRB1*16:02 showed a nonsignificant tendency to be higher in SLE (10.7% vs. 8.1%, and 17.9% vs. 11.1%). Interestingly, the DRB5*01:01 allele linked to DRB1*16:02 in 47.2% of SLE and 37.9% of controls, and the prevalence of the DRB1*16:02‐DRB5*01:01 haplotype was higher in the patients with SLE [12.1% vs. 5.6%, P = 0.044, OR = 2.35 (95%CI = 1.06–5.19)]. The DRB1*16:02 linked to DRB5*02:02 and *02:03 in 18.2% and 31.8% of controls, respectively, and linked to DRB5*02:03 in 32.0% of SLE patients. The frequency of DRB1*03:01 and *15:02 alleles was not increased in Thai SLE. There was no significant association between DRB5*01:01 and any auto‐antibodies or clinical manifestations of SLE. DRB5*01:01 is associated with Thai SLE, and the association is stronger than that of DRB1*15:01. The genetic contribution of DRB5*01:01 is due partially to the linkage disequilibrium between DRB1*16:02 and DRB5*01:01 in the northern Thai population.     

KIR‐HLA‐A and B alleles of the Bw4 epitope against HIV infection in discordant heterosexual couples in Chaco Argentina

Activating and inhibitory killer immunoglobulin‐like receptors (KIR) and their ligands HLA‐Bw4 (loci A and B) were studied by way of establishing whether they can contribute to protection against HIV‐1 infection in highly exposed and persistently seronegative (HESN) patients. Twenty‐three HIV‐1 serodiscordant heterosexual couples, 100 HIV‐1⁺ patients and 200 healthy individuals were included in this retrospective case–control study. HLA typing was performed by means of PCR followed by sequence‐specific oligonucleotide probe reverse hybridization. KIR3DL1 and KIR3DS1 were studied by PCR sequence‐specific primers. The frequency of KIR3DS1(3DS1/3DL1)‐Bw4 combination was significantly higher in HESN patients versus the discordant couples (P = 0·0003) and HIV‐1⁺ patients (P = 0·0001). Conversely, the KIR3DL1/KIR3DL1 homozygosity was significantly decreased in HESN patients versus the discordant couples (P = 0·00003), and HIV‐1⁺ patients (P = 0·00066). The frequency of HLA‐A*32 and HLA‐B*44 was higher in HESN versus their discordant couples (P = 0·009; P = 0·049), and HIV‐1⁺ patients (P = 0·00002; P = 0·0001). This had greater significance in combination with KIR3DS1 (3DS1/3DL1). KIR3DS1(3DS1/3DL1) could have a greater effect on protection against HIV‐1 infection in HESN patients when bound to a specific HLA allele, in this case HLA‐A*32 and HLA‐B*44, both Bw4 alleles. The differences probably arise both in the HLA alleles and in the subtypes of KIR receptors depending on the ethnic group studied.