Effects of heat inactivation on HIV antibody screening and confirmatory test systems.

Abstract

In order to evaluate the effect of heat inactivation on serum undergoing testing for HIV antibody, 100 heat-inactivated and nonheat-inactivated serum samples were tested by two modifications of Abbott's screening assays for human T-cell lymphotropic virus type-III (lot numbers 1037 and 3036) and by two confirmatory assays (Cambridge BioScience CBre3-EIA; Damon Corporation Western blot). The samples consisted of 75 HIV antibody-negative and 25 HIV antibody-positive sera. The specimens were divided into two equal aliquots. One set was not subjected to heat inactivation, while the others were subjected to heat inactivation at 56 degrees C for 30 min. Heat inactivation had no significant effect on the HIV-position sera; however, heat-inactivated, negative sera evaluated by Abbott lot numbers 1037 and 3036 resulted in false-positive rates of 8% and 7%, respectively. No false positives were generated by the two confirmatory assays; however, the CBre3-EIA recombinant envelope protein assay had a significantly increased optical density reading following heat inactivation of the negative sera. The Western blot procedure used in the study was not affected by heat inactivation.