[Ultrastructural morphological observation on the plasma cells in periodontitis-affected human gingival tissue].

The transmission electron microscope was used to demonstrate the mechanism of immunoreaction in periodontitis-affected gingival tissue. The result showed that the number of plasma cells (PC) was the highest in infiltrated inflammatory cells and with degeneration. According to the variation of ultrastructural features of nuclei; plasma membrane (PM) and cisternae (Ci) of rough endoplasmic reticulum (RER), PC were classified into 4 stages. The chromatin of their nuclei varied from normal, to marginal concentrated, pyknosis, and karyorrhexis. The PM appeared intact, partial loss, to complete loss. The Cisternae showed varying degree of dilatation and the RER was broken into numerous discrete vesicles. The electron density of cisternae varied from low to high, and again low. The number of Russell's bodies varied from rare to increase, and then rare again. At last degenerated PC underwent apoptosis. The results show that the adult periodontitis is related to humoral immunity.