Multiple CD4+ cell kinetic patterns and their relationships with baseline factors and virological responses in HIV type 1 patients receiving highly active antiretroviral therapy.

This exploratory analyses characterizes patterns of lymphocyte recovery in HIV-1-infected patients treated with highly active antiretroviral therapy (HAART) and investigates their relationship with baseline indices and virologic responses. We modeled kinetics of total CD4+ lymphocytes, as well as naive (CD45RA+ CD62L+), and memory (CD45RA- CD45RO+) subsets in 48 patients treated with AZT/3TC/Ritonavir for 48 weeks in ACTG protocol 315. Cell kinetic indices were estimated by nonlinear regression methods and were correlated with baseline factors and virologic responses. Five different kinetic patterns were identified, including biphasic growth, growth-plateau, growth-depletion, decay-recovery, and biphasic decay. Although overall mean lymphocyte responses showed a biphasic increase in cell number, a careful investigation reveals that only one-third of patients actually followed the biphasic growth pattern in CD4+ cell response, while 44% of 48 patients from this study followed the growth-depletion pattern. ...