sheep erythrocytes

[BRIDGES]

>About 30 years ago there was a not-very-good diagnostic test for 
>mononucleosis that involved mixing a sample of the patient's serum
>with sheep erythrocytes.  I think the test was positive if the sheep
>cells clumped.

Mononucleosis is caused by the Epstein-Barr virus, which we now know infects 
B-lymphocytes and disrupts their metabolic pattern. Interestingly, one can 
infect B-lymphocytes in vitro with EBV and the cells are "immortalized", and 
will grow continuously in culture.

The B-lymphocytes can produce antibody, and in response to EBV infection often 
produce an antibody that can agglutinate sheep red cells called "heterophil" 
antibodies. The antibodies are made spontaneously, and are directed against 
particular determinants on sheep red cells. The test is positive in about 80% 
of young adults with mononucleosis, but has been superceded by other more 
specific assays.

ken bridges