Interference between D30N and L90M in Selection and Development of Protease Inhibitor-Resistant Human Immunodeficiency Virus Type 1

Abstract

We studied the evolutionary relationships between the two protease inhibitor (PI) resistance mutations, D30N and L90M, of human immunodeficiency virus type 1 (HIV-1). The former is highly specific for nelfinavir resistance, while the latter is associated with resistance to several PIs, including nelfinavir. Among patients with nelfinavir treatment failure, we found that D30N acquisition was strongly suppressed when L90M preexisted. Thus, D30N/L90M double mutations not only were detected in a very limited number of patients but also accounted for a minor fraction within each patient. In the disease course, the D30N and L90M clones readily evolved independently of each other, and later the D30N/L90M double mutants emerged. The double mutants appeared to originate from the D30N lineage but not from the L90M lineage, or were strongly associated with the former. However, their evolutionary pathways appeared to be highly complex and to still have something in common, as they always contained several additional polymorphisms, including L63P and N88D, as common signatures. These results suggest that D30N and L90M are mutually exclusive during the evolutionary process. Supporting this notion, the D30N/L90M mutation was also quite rare in a large clinical database. Recombinant viruses with the relevant mutations were generated and compared for the ability to process p55 gag and p160 pol precursor proteins as well as for their infectivity. L90M caused little impairment of the cleavage activities, but D30N was detrimental, although significant residual activity was observed. In contrast, D30N/L90M demonstrated severe impairment. Thus, the concept of mutual antagonism of the two mutations was substantiated biochemically and functionally.

Mutation D30N Is Not Preferentially Selected by Human Immunodeficiency Virus Type 1 Subtype C in the Development of Resistance to Nelfinavir

“…In contrast, L90M, like other major protease mutations (e.g., V82A and I84V) is a primary mutation involved in resistance to several PIs including nelfinavir, indinavir, and saquinavir (3,11,19,27). These two mutations rarely appear together on the same isolate (26). In the majority of subtype-B-infected patients developing resistance after failing nelfinavir as their first PI, mutation D30N is selected, while mutation L90M or other primary mutations are selected in a significantly smaller proportion (7,19).…”

Mutation Patterns and Structural Correlates in Human Immunodeficiency Virus Type 1 Protease following Different Protease Inhibitor Treatments

“…Alternatively, enzymes containing D30N together with other primary mutations appear to have decreased activity (28).…”

Rapid Propagation of Low-Fitness Drug-Resistant Mutants of Human Immunodeficiency Virus Type 1 by a Streptococcal Metabolite Sparsomycin

“…The D30N and L90M are common drug-resistant mutations found within HIV-1 protease in HIV-1-infected patients on HAART (Devereux et al, 2001;Kantor et al, 2002;Pellegrin et al, 2002;Sugiura et al, 2002 (Figures 2A and B). The replication of the L90M-carrying mutant was also enhanced in Jurkat and SupT1 cells (Figures 2C and D 13.7 and 10.4 nM, and stavudine, 6.3 and 17.0 nM; an nonnucleoside reverse transcriptase inhibitor, nevirapine, 78.2 and 146.4 nM; and protease inhibitors, nelfinavir, 2.8 and 1.0 nM, indinavir, 4.2 and 3.0 nM, and amprenavir, 3.4 and 3.3 Figure 3A).…”