Immunoglobulins on the surface of human appendix lymphocytes

The proportion of lymphocytes in the appendix and peripheral blood with IgM, IgG, IgA, and IgE cell surface determinants was measured by membrane immunofluorescence. IgM was found on 9.27. of appendix lymphocytes, compared to 3.5% of simultaneously collected peripheral blood lymphocytes (p=0.01). In contrast, IgG was found on 6.3% of peripheral blood lymphocytes compared to only 3.0% of appendix lymphocytes (p=0.2). The difference between IgM and IgG on the appendix lymphocytes, however, was highly significant (p<0.001). There was no difference in the number of cells with IgA or IgE determinants between the two populations. These results indicated that a good proportion of the human appendix lymphocytes are B-cells. The higher level of IgM, if substantiated by further studies, would point to some central role for the human appendix lymphocyte immunologic reactivity.