Potential role for excretory - secretory forms of Glutathione-S-transferase (GST) in Fasciola hepatica.

CERVI L, ROSSI G AND MASIH DT.

PARASITOLOGY

Año: 1999 vol. 119 p. 256 - 256

0031-1820

p class="MsoNormal" style="MARGIN: 0cm 0cm 10pt">The excretory-secretory antigen of Fasciola hepatica (ESA) is involved in the suppressive phenomena of cellular immune responses in rats. The ESA can depress the proliferative response of spleen mononuclear cells and inhibit nitric oxide (NO) production by peritoneal cells. In the present study we identified ESA proteins of ca 24 kDa, which shared significant sequence homology to glutathione-S-transferase (GST) obtained from homogenates of F. hepatica adults, other helminths and different mammals. When the dimeric form of these proteins ca 48 kDa was cultured with rat spleen cells, a significant decrease of proliferative response to Con A was detected, starting from 20 micrograms/ml of ESA protein (P < 0.03). We also observed a significant inhibition of nitrite production by incubation with the dimeric form in normal peritoneal macrophages (P < 0.04). These resu