VARIATIONS OF THE LYMPHOCYTOTOXICITY TEST - AN EVALUATION OF SENSITIVITY AND SPECIFICITY

Multiple variations of the basic lymphocytotoxicity test have been rep orted to increase test sensitivity. Although these modifications are u sed routinely in crossmatch tests, as required by federal regulation, there has been no methodical assessment of the relative sensitivities and specificities of these techniques, with the exception of the well- studied antiglobulin method, We have performed such a comparison and f ound that these modifications do not, uniformly, increase test sensiti vity. We also observed that the effect of a technique modification on test sensitivity as measured by overall lymphocytotoxic antibody titer does not reflect, necessarily, the effect on HLA-specific antibody, I t is widely believed that the antiglobulin method is the most sensitiv e of the lymphocytotoxicity techniques, We observed that while the ant iglobulin method increased overall test sensitivity dramatically, we a chieved a comparable level of sensitivity by either substituting B cel ls for T cells or doubling both the serum and the complement incubatio n times, However, no other technique modification detected as many HLA antibody specificities as did the antiglobulin method, The data prese nted here provide useful guidelines for selecting techniques for HLA t yping, antibody screening, and cross-matching.