[Effect of maternal anti-Trichinella antibodies on intestinal worm burden in sucking mice].

OBJECTIVE: To observe the transfer route of maternal anti-Trichinella antibodies and its effect on intestinal worm expulsion after the sucking mice was infected with T. spiralis. METHODS: Ninety-eight sucking mice (Kunming strain) were divided into 4 groups: mice born and nursed by infected mothers (group A), mice born of normal mothers and fostered by infected mothers (group B), mice born of infected mothers and fostered by normal mothers (group C), mice born of and nursed by normal mothers (group D). Blood was taken from tail veins of 4 groups of sucking mice when they were 14, 21 and 42 days old, respectively. Serum anti-Trichinella antibody level was detected by ELISA using T. spiralis muscle larvae excretory-secretory (ES) antigens. Each sucking mouse were then orally challenged with 200 T. spiralis muscle larvae, and intestinal worm burden was observed 18 h after challenge infection. RESULTS: At 18 h after challenge infection, the mean intestinal worm burden of groups A, B, C and D of sucking mice aged 14 days was 5, 5, 19 and 18 larvae respectively. The worm burden of 4 groups of little mice aged 21 days was 18, 19, 75 and 73 larvae, respectively. Groups A and B of 14 and 21 day old mice fostered by infected mothers were shown to harbor obviously fewer worms than groups C and D of mice fostered by normal mothers (F14 = 10.056, F21 = 35.062, P < 0.01). Serum absorbance (A492) of groups A (0.177, 0.235) and B (0.183, 0.250) of 14 and 21 day old mice was significantly higher than groups C (0.108, 0.105) and D (0.067, 0.065) (F14 = 75.326, F21 = 60.867, P < 0.01). The intestinal worm burden in 4 groups of sucking mice aged 14 and 21 days showed significant negative correlation with their serum absorbance (r14 = -0.621, r21 = -0.756, P < 0.01). The intestinal worm burden in 4 groups of sucking mice aged 42 days was 55, 51, 46, and 60 larvae respectively, with no significant difference (F42 = 0.916, P > 0.05), their serum anti-Trichinella antibodies were negative. The intestinal worm burden in 4 groups of offspring mice aged 42 days showed no correlation with their serum absorbance (r42 = -0.291, P > 0.05). Anti-Trichinella antibodies in sera of sucking mice were detected 6 hours after anti-serum Ig to T. spiralis was intravenously injected into the lactating mothers. CONCLUSION: The maternal anti-Trichinella antibodies have been transferred from mother to filial mice mostly through milk, the antibodies can enhance the worm expulsion from intestine when the sucking mice aged 14-21 days was infected with T. spiralis larvae. no correlation with their serum absorbance (r42 = -0.291, P > 0.05). Anti-Trichinella antibodies in sera of sucking mice were detected 6 hours after anti-serum Ig to T. spiralis was intravenously injected into the lactating mothers. CONCLUSION: The maternal anti-Trichinella antibodies have been transferred from mother to filial mice mostly through milk, the antibodies can enhance the worm expulsion from intestine when the sucking mice aged 14-21 days was infected with T. spiralis larvae.