Dynamics of IL-2 and IL-7 levels during Highly active antiretroviral therapy and their significance / 中国医师杂志

ABSTRACT

Objective The objective of this study was to investigate the course of certain common gamma cytokines ( IL-2 and IL-7 ) and their role on the control of the viral infection in a short term antiviral therapy.Methods A total of 35 adults with chronic HIV infection,responding to combined antiretroviral therapy (cART) guideline criteria were enrolled in this one year follow-up study.After signing an informed consent,20 ml blood were collected from each patient at base line,week 0,week 24 and week 48.1 ml serum collected from each patient was kept at -80 * C until use.Serum concentration of IL-2 and IL-7 was determined using ELISA kit from ebioscience Beijing.CD4 and CD8 cells were counted and quantified using flux cytometry,and serum HIV RNA was quantified using real time PCR.Results All patients had a mean baseline IL-2 level [ (9.67 ± 2.6 ) pg/ml ]lower than the controls [ ( 27.36 ± 5.05 ) pg/ml ].After treatment for 48 weeks,IL-2 increased[ ( 19.8 ± 3.3 ) pg/ml ].However,the mean baseline 1L-7 [ ( 81.74± 20.47 ) pg/ml ]in patients was higher than controls [ ( 2.06 ± 1.52 ) pg/ml ].After treatment for 48 weeks,IL-7 decreased [ (8.36 ± 2.16)pg/ml ].IL-2 showed a significant increase and positive correlation with CD4 cells after HAART initiation (0weekR =0.21,P =0.063,24weekR =0.24,P =0.033,48weekR =0.19,P =0.103; IL-7 showed a significant decrease after HAART initiation but it did not show correlation with CD4 cells.We noted there was a negative correlation between IL-2 and CD4 count in HAART baseline (R =0.28,P =0.012 ),but no correlation between IL-7 and CD4 count from 6 month after HAART.IL-2 showed negative correlation with HIV RNA ( R =- 0.17,P =0.032),but IL-7 showed a relationship with the HIV RNA Conclusions The increase of IL-2 coupled with the decrease of IL-7 revealed a partial restoration of immune response during HAART.However,the absence of relationship with HIV RNA suggested that these cytokines might not be directly involved in the reduction of viral load.