HLA diversity and clinical applications in South Africa

Professor Clive Gray, Head of the Division of Immunology, recently co-authored a review entitled “Human leukocyte antigen (HLA) diversity and clinical applications in South Africa” published in The South African Medical Journal in September 2019.

The major histocompatibility complex (MHC) is called the human leukocyte antigen (HLA) complex in humans. HLA forms an integral part of adaptive T cell immunity by presenting self and non-self peptides to the T cell receptor, this allows allows clonal expansion of responding peptide-specific CD4+ and CD8+ T cells. HLA is also an integral component of the innate immune response, through the binding of killer-cell immunoglobulin-like receptor (KIR) molecules, which regulate the response of natural killer (NK) cells.

The HLA complex is found on the short arm of chromosome 6 and is the most polymorphic region in the human genome. Africans are genetically more diverse than other populations.

Professor Gray and his co-authors pointed out that that information on HLA diversity among southern Africans and notably South Africans is limited. They went on to state that poor information limits the understanding of disease, donor-recipient matches for transplants and disease-specific vaccines.  

In their review, Professor Gray and colleagues discuss the importance of HLA in clinical settings and highlight tools such as HLA imputation which may increase understanding of HLA diversity in South African populations. Better understanding of human genetic diversity will lead to more informed disease association students and donor recruitment strategies into bone marrow registries in South Africa.

Read the paper - Human leukocyte antigen (HLA) diversity and clinical applications in South Africa