Anti-JMH identified in serum and in eluate from red cells of a JMH-negative man.

Anti-JMH was identified in the serum of an 80-year-old JMH-negative man. Before transfusion, his direct antiglobulin test was weakly positive with polyspecific reagents, anti-C3 and anti-IgG. An eluate prepared from his red cells contained anti-JMH. Chromium-51-labeled JMH-positive cells which were weakly incompatible in vitro appeared to survive normally. Following transfusion with three JMH-positive units, the patient's hematocrit increased from 20.7 percent to 32.1 percent.