Development of quality control procedures for the human immunodeficiency virus type 1 antibody enzyme-linked...

A standardized pool of human sera that was positive for human immunodeficiency virus type 1 (HIV-1) antibody was developed. This positive control serum was used to analyze test differences among eight laboratories, among the HIV-1 antibody test kits of three different manufacturers, among different lots of the same test kit, and among pipetting devices and techniques. The standardized pool of human sera was tested 327 times by the different laboratories. In terms of positive tests, a reproducibility of 99.69% was achieved; however, significant test variance among laboratories, among test kit lots, and among pipetting devices and techniques could be demonstrated if the tests were compared on the basis of the net positive optical density (OD) value. This value was calculated by subtracting the cutoff OD value (i.e., the value below which an OD value was considered negative for HIV-1 antibody) from the observed OD value of the standardized pool of human sera. The results obtained suggest that this strategy can be used for proficiency testing, for monitoring the quality of HIV-1 antibody enzyme-linked immunosorbent assay reagents, and for evaluating pipetting devices and techniques.