title: Isolation and biological characterization of non-B HIV type 1 from Kenya.
abstract: The isolation and characterization of primary strains of human immunodeficiency virus (HIV) is a vital tool for assessing properties of viruses replicating in HIV-infected subjects. HIV-1 isolation was carried out from 30 HIV-1-infected patients from a Comprehensive Care Clinic (CCC) after informed consent. Virus was successfully isolated from 9 out of the 30 samples investigated. Seven of the isolates were from drug-naive patients while two were from patients on antiretroviral drugs. The isolates were biologically phenotyped through measurement of the syncytium-inducing capacity in MT2 cells. Six of the isolates exhibited syncytia induction (SI) associated with CXCR4 coreceptor usage while three of the isolates were non-syncytia-inducing (NSI) isolates associated with CCR5 coreceptor usage. In addition, the replication capacity of the isolates was further determined in established cell line CD4(+) C8166. Indirect immunofluorescence assay was used to check the antigen expression on the cells as a supplementary test. HIV-1 isolation success was 70% (7/10) and 20% (2/20) in naive and drug-experienced patients, respectively. The majority of the viral isolates obtained (6/9) were of the SI phenotype, though SI virus strains are rare among non-B subtypes. A significant correlation between virus isolation success and viral load was established. Coreceptor use data for heavily treatment-experienced patients with limited treatment options are scanty and this is the group with perhaps the most urgent need of novel antiretroviral agents.
authors.affiliation: Centre of Virus Research, Kenya Medical Research Institute, Nairobi, Kenya. murkim17@yahoo.com
authors.forename: Joseph K
authors.initials: JK
authors.lastname: Muriuki
authors.forename: Joseph N
authors.initials: JN
authors.lastname: Ngeranwa
authors.forename: Joseph
authors.initials: J
authors.lastname: Mwangi
authors.forename: George
authors.initials: G
authors.lastname: Orinda
authors.forename: Raphael
authors.initials: R
authors.lastname: Lwembe
authors.forename: Samuel
authors.initials: S
authors.lastname: Khamadi
mesh_terms: D000328:Adult; D015496:CD4-Positive T-Lymphocytes; D002460:Cell Line; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect / Q000379:methods; D005784:Gene Amplification; D015699:HIV Envelope Protein gp120 / Q000302:isolation & purification*; D006679:HIV Seropositivity / Q000453:epidemiology* / Q000235:genetics / Q000276:immunology; D015497:HIV-1 / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D006801:Humans; D007630:Kenya / Q000453:epidemiology; D008297:Male; D010641:Phenotype; D019713:Receptors, CCR5 / Q000235:genetics / Q000302:isolation & purification*; D019718:Receptors, CXCR4 / Q000235:genetics / Q000302:isolation & purification*; D014779:Virus Replication
chemical_list: D015699:HIV Envelope Protein gp120; D019713:Receptors, CCR5; D019718:Receptors, CXCR4