Microvascular alterations in the lymph node during the BCG-induced immune response.
Previous studies have shown significant microvascular changes during the evolution of the immune response. In order to assess the BCG-induced microvascular alterations in the lymph node, we injected the left foot pad of 23 rabbits with 1.6 x 10(6) live BCG/kg weight; the right side served as control. Following a period of 1 to 50 days, microangiography and histology of the popliteal lymph nodes were carried out. On the side where BCG was injected, the lymph nodes initially showed a moderately increased cortical, and later, a markedly increased medullary hypervascularity. Histologically, there was mixed mononuclear cellular infiltration followed by granuloma formation. This latter was temporally related to the florid medullary hypervascularity. No significant changes were present on the control side. The hypervascularity induced by BCG was more intense and longer lasting than that seen with other antigens such as Typhoid 0 or bovine serum albumin. The results indicate a prominent vascular component in the BCG-induced primary immune response within the regional lymph node.
D000818:Animals; D001500:BCG Vaccine / Q000276:immunology*; D007111:Immunity, Cellular; D008198:Lymph Nodes / Q000098:blood supply; D008833:Microcirculation; D011817:Rabbits
D001500:BCG Vaccine