the structure of the tonsil would seem to facilitate contact between its lymphoid tissue and antigens in the crypts , and it is postulated that 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 , whilst other primed t cells interact with b cells in the follicle centres .
C0024296
lymphoid tissue
C0004561
b cells