Structure of the non-lymphoid cells during the postnatal development of the rat lymph nodes

Abstract

This study describes the postnatal development of the nonlymphoid cells with special reference to the fibroblastic reticulum cells (FRCs) and interdigitating cells (IDCs). The first lymphocytes of the neonatal lymph nodes are located in the developing deep cortex units (DCUs) identified by the Gomori's technique for reticulin fibres. Ultrastructural studies demonstrate that FRCs form the stroma of the DCUs. By light and electron microscopy, it is demonstrated that FRCs occupy the outer cortex in the following stages of development of the lymph nodes. Thus, FRCs form the stroma of the primary follicles and, later, are transformed in follicular dendritic cells (FDCs) of the germinal centres. Immature or pro-IDCs appear as migrating elements in the deep cortex of lymph nodes of the neonatal rats. The ultrastructure of the pro-IDCs resembles that of the mature IDCs but not that of the phagocytic cells. Pro-IDCs are transformed into mature IDCs whose cytoplasmic expansions contact lymphocytes via tight junctions. Some of these lymphocytes are likely apposed to FRCs of the DCUs. No cells containing Birbeck granules were found in the parenchyma of the lymph nodes during the postnatal development. The role of these nonlymphoid cells is discussed with respect to the immunologic function of mammalian lymph nodes.

Development, maturation and subsequent activation of follicular dendritic cells (FDC): immunohistochemical observation of human fetal and adult lymph nodes

“…There have been several reports describing ontogenetical aspects of FDC and related cells in fetal or newborn lymphoid tissues (lymph nodes or spleen) of experimental animals such as mouse, rat, and sheep. Recent work (Balogh et al 2001;Maeda et al 2001) has directed attention to the immunophenotypical evolution of these particular cells, whereas earlier work exclusively described their distributional and morphological transformation (Williams and Nossal 1966;Groscurth 1980a;Dijkstra et al 1982Dijkstra et al , 1984Villena et al 1983;Imai et al 1986Halleraker et al 1994). In the human system, their description was limited and did not examine the developmental or maturational alteration of the FDC, especially regarding their immunophenotypic evolution, although several reports mentioned a part of morphological and/or immunohistochemical features of FDC in fetal lymphoid tissues (Sakuma et al 1981;Markgraf et al 1982;Westerga and Timens 1989;Asano et al 1993;Muretto 1995).…”

“…These findings are, however, still controversial. In addition, the developmental and/or maturational process of FDC have been scarcely examined, whereas several reports studied some aspects of this subject in experimental animal systems such as mice, rats, and rabbits (Heusermann et al 1980;Villena et al 1983;Dijkstra et al 1984;Imai et al 1986;Imazeki et al 1992;Camacho et al 1998;Maeda et al 2001;Hoshi et al 2001;Balogh et al 2001). Only a few studies have examined the developmental and maturational processes of human FDC (Sakuma et al 1981;Markgraf et al 1982;Muretto 1995).…”

“…Several authors have proposed various cell types as a possible origin of FDC, including fibroblastic reticulum cells or certain stromal cells such as synoviocytes (Heusermann et al 1980;Dijkstra et al 1982Dijkstra et al , 1984Imai et al 1983Imai et al , 1986Villena et al 1983;Imazeki et al 1992;Lindhout and de Groot 1995;Lindhout et al 1999;Bofill et al 2000;Jones et al 2001), bone marrow-derived hematopoietic cells (Parwaresch et al 1983;Kapasi et al 1998), mononuclear phagocytes (Fliedner et al 1990), antigen-transporting cells (Szakal et al 1983), pericytes (Rademakers et al 1988), and endothelial cells (Ruco et al 1991;Muretto 1995). These findings are, however, still controversial.…”

Compartmentalization of Peyer’s Patch Anlagen Before Lymphocyte Entry

“…The first primary follicles, indicated by B cell aggregates, are seen 2 wk after birth in the rat (11-13) and 10 days after birth in the mouse (14,15). In this study, we investigated the process by which the basic structure of PP with segregated compartments is established from the primitive PP anlagen.…”

Surgery and radiotherapy of one rare case with neoplasm derived from fibroblastic reticulum cells of a cervical lymph node

“…Although lymph node accessory cells were recognized nearly 20 years ago (3,24), clinicopathological features of neoplasms derived from fibroblastic reticular cells have only been convincingly described in five cases (1,2,22). Tumours derived from FBRCs, therefore, have not been well documented.…”