In a study of 170 South African children infected with HIV prenatally, researchers believe they have observed similarities between the immune responses of those who avoid developing full-blown AIDS and those of primate species that carry Simian Immunodeficiency Virus (SIV), the disease from which human immunodeficiency virus (HIV) derives.
In a study of 170 South African children infected with HIV prenatally, researchers believe they have observed immune response similarities between those who avoid developing full-blown AIDS and the primate species that carry Simian Immunodeficiency Virus (SIV), the disease from which human immunodeficiency virus (HIV) derives. Though disease progression is faster in childhood than adulthood and as many as 99% of those who are HIV-positive develop AIDS, that at least 5% of children born with the disease may avoid that outcome even in the absence of treatment.
The “infected but healthy” non-progressing children actually exhibit relatively low levels of immune activation. In these patients, the viral reservoirs, where particles of HIV hide and replicate, are mostly restricted to CD4+T cells, which have a short lifespan in the body.
Published last week in Science Translational Medicine, the researchers describe this as a “striking resemblance” to the immune response found in monkeys that have long carried SIV. Though the virus replicates freely in them, their immune systems do not appear to be compromised. On the other hand, the vast majority of HIV-positive humans display chronic immune activation even while anti-retroviral therapy (ART) reduces the amount of virus in the body.
The research is a fascinating look into adaptive natural defense mechanisms against HIV, particularly coming from a hotbed of the disease.
The overall population of those whose HIV does not progress to AIDS has previously been placed around the 5% number that this study cites. It is important to note that the average age of the children in the cohort was about 8 years old, and because they did not outwardly display the disease, many only were diagnosed once their mothers were. Other previous work has required at least 8 or in some cases 10 years of confirmed infection without progression to consider a patient a “non-progressor.”