Distribution of HLA-DRB1 alleles in BRICS countries with a high tuberculosis burden: a systematic review and meta-analysis

Rev Soc Bras Med Trop. 2021 Jul 23:54:e00172021. doi: 10.1590/0037-8682-0017-2021. eCollection 2021.

Abstract

Introduction: Tuberculosis (TB) is the leading cause of death worldwide caused by a single infectious disease agent. Brazil, Russia, India, China, and South Africa (BRICS) account for more than half of the world's TB cases. Bacillus Calmette-Guérin (BCG) remains the only vaccine available despite its variable efficacy. Promising antigen-based vaccines have been proposed as prophylactic and/or immunotherapeutic approaches to boost BCG vaccination. Relevant antigens must interact with the range of human leukocyte antigen (HLA) molecules present in target populations; yet this information is currently not available.

Methods: MEDLINE and EMBASE were systematically searched for articles published during 2013-2020 to measure the allelic frequencies of HLA-DRB1 in the BRICS.

Results: In total, 67 articles involving 3,207,861 healthy individuals were included in the meta-analysis. HLA-DRB1 alleles *03, *04, *07, *11, *13, and *15 were consistently identified at high frequencies across the BRICS, with a combined estimated frequency varying from 52% to 80%. HLA-DRB1 alleles *01, *08, *09, *10, *12, and *14 were found to be relevant in only one or two BRICS populations.

Conclusions: By combining these alleles, it is possible to ensure at least 80% coverage throughout the BRICS populations.

Publication types

  • Meta-Analysis
  • Systematic Review

MeSH terms

  • Alleles
  • Brazil
  • China
  • HLA-DRB1 Chains / genetics
  • Humans
  • India
  • Russia
  • South Africa
  • Tuberculosis*

Substances

  • HLA-DRB1 Chains