Subscribe
SCIENTISTS at the Cancer Research Institute (CRI) in Bombay say they now have the expertise to culture the AIDS virus in the laboratory. "This is a first for the country," adds Robin Mukhopadhyaya, who set up a state-of-the-art AIDS research laboratory at CRI about two-and-a-half years ago.
This is considered an important step towards making Indians researchers independent of foreign expertise. "We no longer need to depend on Western scientists for access to the AIDS virus," explains Mukhopadhyaya. "We can study our cultured samples in detail now. Moreover, we can determine later the efficacy of various drugs on indigenous AIDS virus strains."
Human Immunodeficiency Virus (HIV) 1 and HIV 2 are the main AIDS viruses, but HIV 1 is known to have five different families. For example, scientists note, the HIV 1 virus found in Taiwan belongs to a different family from the one found in Africa. These differences in the virus are determined by genetic sequence. If the sequence varies by more than 30 per cent, scientists rate it as belonging to a different family.
Mukhopadhyaya, who has worked at the US National Institutes of Health in Maryland, one of the world's most advanced AIDS research laboratories, says the ability to culture the AIDS virus is important because the indigenous HIV strain may be different from those found elsewhere in the world. "If we are to tackle the disease in India, we must know what our virus exactly is," he adds.
As yet only three samples of the Indian virus have been partially sequenced at a German laboratory and a 20 per cent difference was observed. Experts say HIV from more than one family may occur in India, as transmission varies from one part of the country to another. In Manipur, for example, HIV is transmitted by drug addicts who share intravenous needles, but in Bombay, the primary causes are homosexual and heterosexual commercial sex.
The CRI effort involved blood samples from AIDS patients available with Dr J K Mainar at the Gokuldas Tejpal Hospital in Bombay. The infected blood was cultured with immune system cells that HIV enters and attacks, such as normal CD4+ cells or T helper cells. To culture the AIDS virus using this technique, an expensive imported cell growth factor called Interleukine 2 is added.
As an alternative, CRI scientists are exploring ways to infect self-multiplying, cancerous T helper cells, which will enable the scientists to maintain the viral stock on a continuous basis. The cultured virus, say experts, can be stored in liquid nitrogen or at -800 C for some months.