HIV-1 biological phenotype in long-term infected individuals evaluated with an MT-2 cocultivation assay.
OBJECTIVE
We have previously demonstrated that detection of syncytium-inducing (SI) HIV-1 in asymptomatic seropositive individuals is associated with rapid progression to AIDS. In the present study, we sought to develop and evaluate an HIV-1 phenotyping assay for the screening of large numbers of individuals.


METHODS
Efficiency of HIV-1 isolation from patient peripheral blood mononuclear cells (PBMC) was studied with donor PBMC or seven different CD4+ T-cell lines as target cells. The biological phenotype of sequential isolates from 20 long-term asymptomatic HIV-1-seropositive individuals was determined by two different assays.


RESULTS
Non-SI isolates, efficiently recovered by cocultivation with donor PBMC, were never isolated with T-cell lines as target cells. Direct cocultivation with MT-2 cells, but not with six other CD4+ T-cells, resulted in the efficient recovery of SI isolates. HIV-1 MT-2 tropism and SI capacity were shown to be coupled properties at the clonal level. SI isolates emerged in 10 out of 20 longitudinally-studied individuals. In these long-term infected individuals, appearance of SI isolates was associated with progression to AIDS.


CONCLUSIONS
Direct cocultivation of patient PBMC with the MT-2 cell line is a sensitive, specific and convenient method to detect SI isolates. The availability of an assay suitable for the screening of large groups allows further study of the value of HIV-1 biological phenotyping as a prognostic marker.
Koot
M
M
Department of Clinical Viro-Immunology, Central Laboratory of The Netherlands Red Cross Blood Transfusion Service, Amsterdam.
Vos
A H
AH
Keet
R P
RP
de Goede
R E
RE
Dercksen
M W
MW
Terpstra
F G
FG
Coutinho
R A
RA
Miedema
F
F
Tersmette
M
M
D000163:Acquired Immunodeficiency Syndrome / Q000382:microbiology* / Q000503:physiopathology; D002460:Cell Line; D002478:Cells, Cultured; D015726:Giant Cells / Q000166:cytology*; D015658:HIV Infections / Q000382:microbiology* / Q000503:physiopathology; D015497:HIV-1 / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology*; D006801:Humans; D009000:Monocytes / Q000166:cytology / Q000382:microbiology; D010641:Phenotype; D013601:T-Lymphocytes / Q000166:cytology / Q000382:microbiology; D014779:Virus Replication