Association between NDO-LID and PGL-1 for leprosy and class I and II HLA alleles in an indigenous community in Southwest Amazon.
The frequencies of the HLA alleles in the Puyanawa indigenous reserve population and their association with the NDO-LID and ELISA PGL-1 rapid serological test was assessed. This was a cross-sectional study with an epidemiological clinical design conducted in two indigenous communities in the state of Acre, Brazil. Blood was collected in a tube with EDTA to identify HLA alleles and perform serological tests. DNA was obtained using the salting out procedure. The LabType™ technique (One-Lambda-USA) was used for HLA class I (loci A*, B* and C*) and II (loci DRB1*, DQA1* and DQB1*) typing. Allele frequency was obtained by direct count, and the chi-square test was used to assess the association with the NDO-LID and PGL-1 tests. The most frequent alleles in the two communities were: HLA-A*02:01, HLA-B*40:02, HLA-DRB1*16:02, HLA-DQA1*05:05 and HLA-DQB1*03:01. The allele HLA-C*04:01 was the most common in the Barão community, and the allele HLA-C*07:01 in Ipiranga. Among individuals who presented seropositivity to the NDO-LID test, the association with alleles HLA-A*02 (43.18% vs 24.8%, p=0.03, OR=2.35) and HLA-B*53 (6.83% vs 0.0%, p=0.03, OR=8.95) was observed in the Barão community. HLA-B*15 was associated with non-seroconversion to the NDO-LID test in Ipiranga. In both communities, HLA-B*40 and HLA-C*03 were associated with positive serological response to ELISA PGL-1. The HLA class I and II alleles most frequently found in this study have already been described among Terena indigenous groups, and HLA class I contributes to seroconversion to NDO-LID and PGL-1 tests in inhabitants of the Barão and Ipiranga communities.