Profile of human leukocyte antigen class I alleles in patients with dengue infection from Western India.

Human leukocyte antigen (HLA) class I alleles are known to affect the cytotoxic T lymphocyte responses and influence susceptibility to viral infections. The objective of the present study was to find out whether HLA class I alleles are associated with clinical manifestations of dengue virus infection. The profile of HLA class I alleles were investigated in 224 human subjects [85 dengue fever (DF) cases, 29 dengue hemorrhagic fever (DHF) cases and 110 healthy controls (HCs)] from Western India using PCR based methods. Results revealed significantly higher frequency of HLA-A(∗)33 in DF cases compared to HCs [P = 0.032, Odds ratio (OR) 2.12]. The frequency of HLA-A(∗)02:11 was higher in DHF cases compared to DF cases. The frequency of HLA-B(∗)18 was significantly higher in dengue (DEN) cases [P = 0.047 Pc = 0.846, OR 3.53]. The frequency of HLA-Cw(∗)07 allele was significantly higher in DEN cases [DEN vs. HCs: P = 0.0120, Pc = 0.168, OR 2.00]. Significance was observed even when the cases were categorized in to DF and DHF [DF vs. HCs: P = 0.0349, Pc = 0.49, OR 1.87; DHF vs. HCs: P = 0.0399, Pc = 0.56, OR 2.4]. The combined frequency of HLA-Cw(∗)07 with HLA-DRB1(∗)07/(∗)15 genotype was significantly higher in DHF cases as compared to DF and HCs [DHF vs. HCs: P = 0.022, OR 5.31; DHF vs. DF: P = 0.027, OR 5.49]. On the other hand, the frequency of combination of HLA-Cw(∗)07 without HLA-DRB1(∗)07 was significantly higher in DF cases compared to HCs [DF vs. HCs: P = 0.002, OR 2.42 (1.28-4.55)]. The results suggest that HLA-A(∗∗)33 may be associated with DF while HLA-B(∗)18 and HLA-Cw(∗)07 alleles may be associated with symptomatic dengue requiring hospitalization. In the presence of HLA-DRB1(∗)07/(∗)15 genotype, HLA-Cw(∗)07 is associated with increased risk of developing DHF while in the presence of other HLA-DRB1 alleles, HLA-Cw(∗)07 is associated with DF.