Function of Serum Adenosine Deaminase as an Indicator of Immune Status in HIV Patients treated with Combination Antiretroviral Therapy

Abstract

Acquired immunodeficiency syndrome (AIDS) is one of the greatest public health and social problems threatening the human race. The trend of annual AIDS deaths is showing a steady decline since the implementation of the free Anti-Retroviral Therapy (ART) program in India (2004). HIV infection is characterized by replication of virus by abnormal non specific immune activation and persistent inflammation. Adenosine deaminase (ADA) has a cytokine-like co-stimulatory role in T cell proliferation which is independent of catalytic activity. Therefore, we decided to study the role of ADA as an indicator of immune status in HIV patients treated with combination antiretroviral therapy (cART). Adenosine deaminase activity (ADA) in HIV patients was estimated before and after 3 months interval of antiretroviral therapy (ART) up to 9 months. The study included 150 HIV positive patients between age group of 20-50 years from ICTC (Integrated Counseling and Testing Centre) and ART centre. Venous blood samples were collected in plain bulb to estimate serum ADA activity before and after 3 months interval upto 9 months of ART. Serum ADA activity was estimated using colorimetric method of Giusti and Galanti. Activity of serum ADA was significantly raised before and after 3 months interval of ART with decrease in CD4 cell count. After 6 months, increased ADA activity started declining and comes to near normal after 9 months of ART (p<0.001). Elevated serum adenosine deaminase activity in HIV patients is an indicator of T-cell activation. Serum ADA activity along with other markers can be used as a prognostic marker to monitor response to antiretroviral therapy and immunocompetence in HIV patients.