抄録
The white pulp (WP) and marginal zone (MZ) constitute the immunologically active compartment of the human spleen. In the WP, there are two distinct regions, the periarteriolar lymphoid sheath (PALS) and the lymph follicle (LF). The basic framework of the PALS, LF and MZ consists of reticulum cells and reticulin fibers. A distinct microenvironment, is formed in the reticular framework of the PALS, LF and MZ, respectively. Immunophenotype of the reticulum cells is heterogeneous in the PALS, LF and MZ. Composition of extracellular matrix proteins of the reticulin fibers is also different in the PALS, LF and MZ. The reticular framework of the PALS, LF and MZ is specialized into heterogeneous components and plays a role in the formation of the distinct microenvironment specific for lymphoid subclasses and the lymphocyte homing and segregation mechanism. In the ontogeny of the PALS, LF and MZ, the development of the heterogeneity of the reticular framework is related with the organization of the PALS, LF and MZ.
