IMMUNOGLOBULIN-CONTAINING CELLS IN HUMAN TONSILS AS DEMONSTRATED BY IMMUNOHISTOCHEMISTRY

  • 1 January 1977
    • journal article
    • research article
    • Vol. 28  (1) , 103-115
Abstract
Intracellular immunoglobulin [Ig] was demonstrated in human palatine tonsils by the unlabeled antibody peroxidase-antiperoxidase complex (PAP) method in which rabbit antiserum to a range of human Ig was linked to the PAP complex by an intermediate stage of swine antiserum to rabbit Ig. The effects of different methods of fixation and processing were compared, formol-saline fixation giving the best results. The PAP technique proved greatly superior to the fluoresein isothiocyanate (FITC)-based technique, not only in sensitivity but in permitting study of the finer histological and cytological features. The lymphoid follicles apparently have 3 distinct zones, 2 forming the follicle center [zones (a) and (b)] and the 3rd [zone (c)] the lymphocyte cap. Ig synthesis appeared to begin in the cells in zone (b). IgG, IgA, IgM, IgE and IgD were present in all tonsils, with IgG predominating, confirming that the tonsil resembles lymph nodes more closely than it does alimentary lymphoid tissue. Some follicles contained more than one type of Ig. The tonsil appears to have a well-developed T[thymus-derived]cell-dependent area, the lymphoid follicles forming a B[bone marrow-derived]-cell area. The structure of the tonsil would seem to facilitate contact between its lymphoid tissue and antigens in the crypt. Some T cells within the crypt epithelium, after contact with antigen, may leave the tonsil by the efferent lymphatics and enter the peripheral circulation by the thoracic duct, while other primed T cells interact with B cells in the follicle centers. Some B cells may then start to synthesize Ig, while others become memory cells in the lymphocyte cap of the follicle.