The hallmark of AIDS is profound immunosuppression, which results from what condition?

The hallmark of AIDS (Acquired Immunodeficiency Syndrome) is indeed profound immunosuppression, which primarily results from the severe loss of CD4 T-helper cells. CD4 T-helper cells play a crucial role in the immune system by helping to orchestrate the immune response against pathogens, facilitating the activity of not only B cells, which produce antibodies, but also other immune cells involved in eradication of infections.

As HIV (Human Immunodeficiency Virus) targets and infects CD4 T cells, particularly during the later stages of infection, the overall count of these cells declines significantly. This depletion leads to a weakened immune response, making the individual more susceptible to opportunistic infections and certain cancers that would normally be prevented by a healthy immune system. The profound immunosuppression characteristic of AIDS is thus directly linked to this loss of CD4 T-helper cells, confirming that option reflecting this condition is indeed the correct response.