The Problem of the Acquired B Antigen in Forensic Serology

The acquisition of a B-like antigen by red cells has been reported by many workers, and it has now been well established that this is due to certain bacteria which produce substances identical with, or very similar to, the A, B and H blood group substances. Forensic serologists encounter the acquired B antigen in blood grouping problems and two such examples are described. Experiments have been devised where seminal stains, muscle tissues and blood stains are subjected to conditions favourable to the production of acquired B. Finally, the possibility of producing a reagent which will detect the normal B antigen but not the acquired B antigen, has been investigated.