Germinal centre and B lymphoblast responses in the parathymic lymph nodes after localized peritoneal inflammation.

Inflammatory cells from a focus of peritoneal inflammation are known to migrate from the peritoneal cavity to the parathymic lymph nodes inducing a B-lymphocyte response in the medulla. The present study demonstrates that the medullary response is preceded by an expansion of the germinal centres with evidence of blast transformation. The number of cells in the lymphocytic corona is increased with a significant increase in the percentage of large cells containing immunoglobulin. This cellular expansion involves immunoglobulin M and immunoglobulin G containing cells.