Discordant response to antiretroviral therapy: HIV isolation, genotypic mutations, T-cell proliferation and cytokine production.
OBJECTIVE
To study virologic and immunologic factors associated with discordant treatment response in HIV-infected patients receiving highly active antiretroviral therapy (HAART).


METHODS
Study participants included a total of 27 patients: (a) 10 discordant patients (mean CD4+ cell count, 396.1 x 10 cells/l; mean HIV-RNA, 5.4 log copies/ml); (b) seven responder patients (mean CD4+ cell count, 997.5 x 10 cells/l); and (c) 10 failing patients (mean CD4+ cell count 66.5 x 10 cells/l; mean HIV-RNA, 5.4 log copies/ml).(10) (10)


METHODS
The HIV-1 isolation rate and biological phenotype, drug resistance genotypic mutations of HIV-1 strains, recall and HIV-1-specific antigen lymphocyte proliferation (LP), and interleukin (IL)-15 production were studied.


RESULTS
Virus isolation was obtained in 30% of discordant patients, and in 100% of failing patients. A higher replication constant was reported in discordant patients. No difference in the number of drug resistance mutations and biological phenotypes of HIV-1 was found in discordant patients with respect to failing patients. Discordant patients developed positive LP responses to and HIV-1 p24. LP in response to, HIV-1 p24 and gp160 was positive in responder patients. No significant LP was found in failing patients. Increased levels of IL-15 after stimulation with lipopolysaccaride (LPS) and were found in both discordant patients and responder patients. Conversely, a strong reduction of IL-15 levels was observed in failing patients.


CONCLUSIONS
The present results suggest that decreased virus isolation rate, restoration of both lymphocyte proliferation and IL-15 production are factors involved in the discordant antiretroviral therapy response of HIV-infected patients.
D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D018791:CD4 Lymphocyte Count; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D002176:Candida albicans; D024882:Drug Resistance, Viral; D005260:Female; D015658:HIV Infections / Q000150:complications / Q000188:drug therapy* / Q000276:immunology / Q000821:virology; D015497:HIV-1 / Q000187:drug effects / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D006801:Humans; D019409:Interleukin-15 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D019562:Viral Load; D014779:Virus Replication / Q000187:drug effects
D019380:Anti-HIV Agents; D019409:Interleukin-15