Mechanisms of HIV non-progression; robust and sustained CD4+ T-cell proliferative responses to p24 antigen correlate with control of viraemia and lack of disease progression after long-term transfusion-acquired HIV-1 infection

Dyer, Wayne B; Zaunders, John J; Yuan, Fang Fang; Wang, Bin; Learmont, Jennifer C; Geczy, Andrew F; Saksena, Nitin K; McPhee, Dale A; Gorry, Paul R; Sullivan, John S

When this prospective study began in 1994, 13 LTNP were identified in the NSW TAHIV cohort according to the original guidelines for classifying LTNP: at least 10 years infection, stable CD4 T cell counts >500 cells/μl, and no history of ART [27, 28] . Subsequently, loss of LTNP status was defined by any of the following events: a consistent decline in CD4 T cell counts below 500/μl, commencement of ART, and after viral load testing became routine, plasma viraemia >5000 copies/ml. Elite non-progressors were also defined by viraemia suppressed to <50 copies/ ml in addition to the above criteria. Disease progression was defined by a CD4 T cell count of <200 and/or plasma viraemia >100,000 copies/ml.