Sp. Lozzi et al., INVOLVEMENT OF REGIONAL LYMPH-NODES AFTER PENETRATION OF SCHISTOSOMA-MANSONI CERCARIAE IN NAIVE AND INFECTED MICE, Memorias do Instituto Oswaldo Cruz, 91(4), 1996, pp. 491-498
The parotid lymph nodes of naive and previously infected Balb/c mice w
ere studied after, respectively, infection and re-infection with cerca
riae of Schistosoma mansoni via the ears. Schistosomula were able to p
ass through the lymph node by following the lymph flow or by penetrati
ng the veins of the medullary cords. The number of nodal mast cells wa
s higher from day 2 to 6 of primary infection; and from day 5 to 11 of
re-infection. The amount of degranulating mast cells was significantl
y higher at day 4 of infection and at day 1 of re-infection. Eosinophi
ls characterized the nodal inflammatory processes observed after day 5
in both primarily-infected and re-infected mice. However, only in the
latter the eosinophils were able to adhere to the larval surface. In
primarily-infected mice, no intranodal larva presented signs of degene
ration. In contrast in re-infected animals, some degenerating larvae w
ere found inside eosinophilic infiltrates. The eosinophils reached the
nodal tissue by migrating through the high endothelial venules and th
eir collecting veins.