Histological observations on rat popliteal lymph nodes after blockage of their afferent lymphatics.

CLEC-2 is required for development and maintenance of lymph nodes

“…28 However, due to the early lethality of knockout mice characterized by impaired formation of the lymphatic vessels, the requirement of the lymphatic vasculature for LN anlage development is still subject to debate. The 2 knockout mouse models used in this study showed different degrees of malformation in the lymphatic vasculature with a lymphatic phenotype characterized by a reduced number of LEC forming in the /Tie2Cre embryos, even though LTi cells were recruited into the LN anlagen, mature LTo cells fail to persist, suggesting that a normal lymphatic vasculature is critical for the stabilization and persistence of the LN anlage stroma.…”

Formation of lymph follicles in draining lymph nodes after local injection of various antigenic substances in mice.

“…Although accumulating evidence indicates that the lymph follicle is a reactive structure which develops in the lymphoid organ in response to antigenic stimuli and which fades away when the magnitude of the stimulus decreases (SJovALL and SJovALL,1930;CONWAY, 1937;SAINTE-MARIE and SIN, 1970;HosHI et al, 1985), the character of the stimuli effective to induce follicle formation is not clearly defined. Our previous study (HOSHI et al, 1984) has shown that when locally injected, phytohemagglutinin (PHA) induces germinal centers in almost every existing follicles in the draining node but eventually fails to stimulate the formation of new lymph follicles, whereas bacterial lipopolysaccharide (LPS) not only induces germinal centers in existing follicles but also produces new primary follicles, which soon develop germinal centers.…”

A histological and experimental study on the fate of an increased number of lymph follicles produced in the mouse popliteal lymph node by exogenous antigen stimulation.

“…liteal node was found to remain virtually unchanged for at least 17 weeks, indicating that most normally developed lymph follicles persist for a long time. Our previous observations (HOSHI et al, 1981(HOSHI et al, , 1985WATANABE and HORIE, 1987) also showed that in untreated rats, guinea pigs and C3H/HeN mice, the popliteal nodes contained relatively constant numbers of lymph follicles for periods of weeks or months, although the number of follicles per popliteal node varied according to animal species and strain. Moreover, it has been documented that the persistence of lymph follicles requires continuous stimulation with antigen (SAINTE-MARIE and SIN, 1970;HosHI et al, 1985).…”

“…Our previous observations (HOSHI et al, 1981(HOSHI et al, , 1985WATANABE and HORIE, 1987) also showed that in untreated rats, guinea pigs and C3H/HeN mice, the popliteal nodes contained relatively constant numbers of lymph follicles for periods of weeks or months, although the number of follicles per popliteal node varied according to animal species and strain. Moreover, it has been documented that the persistence of lymph follicles requires continuous stimulation with antigen (SAINTE-MARIE and SIN, 1970;HosHI et al, 1985). The fact that a popliteal node contains a constant number of lymph follicles for a long period may imply that it receives a continuous and relatively constant level of antigenic stimulation via the afferent lymphatics.…”

“…It has been repeatedly shown that lymph follicles can be activated by non-specific antigens as well as specific ones (see, for example, NOSSAL et al, 1968;KLAUS et al, 1980;HosHI et al, 1985). Therefore, if atrophied or resting follicles actually persist, these together with other existing follicles can be activated by non-specific antigen.…”