Frequency of HLA antibodies in south India

Sera from 4088 pregnant women (649 antenatal bleeding and 3439 post-partum bleeding) living in Madurai, were collected and screened for anti-HLA. A, B and DR antibodies. 696 of them were screened for anti-HLA DR antibodies. Ten per cent (65/649) of antenatal sera and 13 4% of post-partum sera (463/3439) were positive for HLA A and B antibodies: nonetheless the percentage of monospecific sera were almost the same in both. Screening for HLA DR antibodies were carried out using platelet absorption in test tray technique: seventy three of 696 (10.5%) were positive. The incidence of anti-HLA A, B antibodies correlates to the allelic frequencies in the population. Thus in India, collection and screening post-partum haemorrhage is the simplest and cost effective method of acquiring polyclonal sera for routine laboratory and diagnostic use.