Second generation effects of maternal ethanol consumption on immunity to Trichinella spiralis in female rats

The deleterious effects of maternal ethanol consumption on neonatal immune development and early immune responses has been well documented. However, t he effects of such neonatal exposure to maternally consumed ethanol on the neonates' immune responses in their adult life, especially in combination w ith additional ethanol exposure, has received little attention. For these e xperiments, female rats were fed on either 6% ethanol or pair-fed isocalori c control Lieber-DeCarli liquid diets for 30 days prior to, and during, pre gnancy and lactation. One day after weaning their pups, the mothers were in fected with 1000 Trichinella spiralis larvae, and maintained on diets for a n additional 20 days. At this time, they were challenged with 2000 T. spira lis larvae, killed 3 days later, and their immune status determined. These animals served as the first generation alcohol animals. Their female offspr ing served as the experimental second generation animals. These animals rec eived maternal ethanol during pregnancy and lactation and control diet duri ng their juvenile period (from weaning to 90 days of age). They were then s ubjected to a schedule of ethanol or pairfeeding, identical to the first ge neration dams. Two groups of second generation animals were established: Gr oup 1 was exposed to ethanol during their dam's pregnancy and lactation per iods only, with no subsequent ethanol treatment; Group 2 received ethanol d uring their darn's pregnancy and lactation periods and then again throughou t their adult experimental period. Our previous studies showed only minimal changes following a secondary challenge in T. spiralis-immunized rats; how ever, neonates born to alcohol-consuming mothers did show some depressed se condary immune responses when challenged soon after weaning. We chose to us e a secondary immune challenge to assess further immune alterations in seco nd generation adult animals. No differences between any of the ethanol and pair-fed groups were observed in intestinal worm burdens, which is similar to data previously reported for adult alcohol-consuming animals. However, s econd generation group 2 animals demonstrated significantly reduced prolife ration responses to T. spiralis antigen and Concanavalin A (Con A) stimulat ion relative to the ethanol first generation and to the second generation G roup 1 animals. This group also demonstrated significantly lower absorbenci es in the ELISA assay for specific IgM and Ige anti-T. spiralis antibodies than the pair-fed, ethanol first and second generation Group 1 animals. The proportion of total T cells and cytotoxic T cells was significantly lower and the proportion of natural killer cells was elevated in both second gene ration ethanol Groups 1 and 2 relative to the ethanol first generation and pair-fed groups. In addition, Group 2 second generation animals showed sign ificantly lower proportions of total leukocytes and T cells than Group 1 se cond generation animals. Although secondary immune responses to T. spiralis infection were not altered in rats exposed to ethanol only as adults, expo sure to maternal ethanol does affect some specific immune responses in seco nd generation adult life and maternal exposure may exert cumulative immune effects in concert with later consumption of ethanol by offspring born to a lcoholic mothers.