Differential course of HIV-1 infection and apolipoprotein E polymorphism

We studied the course of infection with human immunodeficiency virus type 1 (HIV-1) in relation to apolipoprotein E (APOE) polymorphism found for 209 Italians treated at Infectious Disease Clinics in Rome and Modena. Clinically, patients were classified into four groups according to the yearly rate of decline in CD4+ cell count (LTNP: long-term non-progression; SLOW, 'NORMAL' or RAPID). Patients at both extremes of the clinical spectrum, i.e. those who rapidly progressed to AIDS and those with stable high CD4 cell counts, had few APOE ε4 and ε2 alleles (P = 0.04). Detailed clinical information was then used to construct four model-based clinical profiles using grade-of-membership analysis (GoM), predictive of APOE genotypic frequencies: 1. The clinical profile associated with good long-term prognosis lacked ε2 (P=0.01); 2. Disease progression to AIDS was associated with ε4 and ε2, most evident for zidovudine-lamivudine regimens without a protease inhibitor (P = 0.03); and, 3. AIDS patients had low ε4 and ε2 frequencies, consistent with a high mortality rate among ε4+ and ε2+ AIDS patients. These findings suggest allele-specific immunomodulatory effects involving inherited APOE isoform important enough to alter the clinical course of HIV infection and, possibly, drug efficacy. They imply a connection between lipid metabolism and immunity potentially relevant to common disorders. © 2007 Versita Warsaw and Springer-Verlag.