Differential syncytium-inducing capacity of human immunodeficiency virus isolates: frequent detection of syncytium-inducing isolates in patients with acquired immunodeficiency syndrome (AIDS) and AIDS-related complex

Abstract

Human immunodeficiency virus isolates were studied with respect to syncytium-inducing capacity, replicative properties, and host range. Five of 10 isolates from patients with acquired immunodeficiency syndrome (AIDS) and AIDS-related complex were able to induce syncytia in cultures of peripheral blood mononuclear cells (MNC). In contrast, only 2 of 12 isolates from asymptomatic individuals had syncytium-inducing capacity. Syncytium-induciiig isolates were reproducibly obtained from the same MNC sample in over 90% of the cases, independent of the donor MNC used for propagation. Syncytium-inducing capacity was shown to be a stable property of an isolate, independent of viral replication rates. Evidence was obtained that the high replication rate of syncytium-inducing isolates observed during primary isolation may be due to higher infectivity of these isolates. The finding that only syncytium-inducing isolates could be transmitted to the H9 cell line is compatible with this higher infectivity. The frequent isolation of syncytium-inducing isolates from individuals with AIDS-related complex or AIDS and the apparent higher in vitro infectivity of these isolates suggest that syncytium-inducing isolates may unfavorably influence the course of human immunodeficiency virus infection.

Rate of development of mutation at codon 215 of HIV‐1 reverse transcriptase and its predictive factors at the time of initiation of zidovudine therapy

“…The virus SI phenotype has been associated with a poor prognosis [34], but the contribution to immune deterioration is unknown. Its lack of association with the development of resistance is in some way contradictory as SI viruses present a rapid/high replicative phenotype in vitro [35]. However, no evidence is yet available to support the hypothesis that this high replicative capacity also exists in vivo.…”

Targeted inhibition of immunodeficiency virus replication in lymphocytes through retroviral mediated gene transfer

“…Biological heterogeneity of HIV or SIV is reflected by differences in host range, replicative properties, and cytopathic effect in infected cells [7,12,28,32]. Restriction endonuclease mapping and sequence analyses of HIV [24] and SIV [3] isolates, as well as the patterns of neutralization of different isolates by antibodies, also demonstrate genetic diversity, particularly in the envelope glycoprotein [6].…”

Neurotropism of Human Immunodeficiency Virus

“…Slowly and rapidly replicating viruses differ not only in replicative capacity but also in cytopathogenicity in PBMC cultures (21). Change from slow/low to rapid/high virus may occur in the same individual over time concomitant with the progressive HIV related disease (18,22,23). It has been suggested (22,23) that this change signals the emergence of HIV variants with increased virulence.…”

“…Change from slow/low to rapid/high virus may occur in the same individual over time concomitant with the progressive HIV related disease (18,22,23). It has been suggested (22,23) that this change signals the emergence of HIV variants with increased virulence. It is, however, more likely that emergence of virus variants with increased replicative capacity reflects the inability of the immune system to control virus replication.…”