Effects of multiple freeze thaws and various temperatures on the reactivity of human immunodeficiency virus antibody using three detection assays

The effects of multiple freeze-thaw cycles and various temperatures (-20°C, 4°C, 25°C, 37°C) on the reactivity of human immunodeficiency virus (HIV) antibodies were evaluated using current ELISA, recombinant, and Western blot methodologies. Twenty consecutive freeze-thaw cycles and storage of specimens at -20°C and 4°C for 57 days resulted in no loss of HIV antibody reactivity nor false positive samples. Maintenance of clinical specimens at 25°C and 37°C for 57 days resulted in some loss of HIV antibody reactivity, but all positive and weakly reacting samples remained positive, and negative samples were unaffected.