<prompt> Which is not heterophile agglutination test?Weil-Felix testWidal testPaul-Bunnel, testStreptococcus MG  <response>: Ans. b Widal Test Ref. Ananthanarayan 8e, p 93 The same or closely related antigen may sometimes occur in different biological speciesclasses, etc. It is called heterogenetic or heterophile antigen, e.g. Forssman antigen for Pneumococcus, Salmonella. Weil Felix reaction between proteus and Rickettsia. Paul Bunnell test in infectious mononucleosis. Cold agglutination test in primary atypical pneumonia. Streptococcus MG agglutination. Antigen between E. coli and human RBC of B. Remember Widal test is tube agglutination test. 