AUTHOR=Burdick Sanchez Nicole C. , Mitchell Ty , Broadway Paul R. , Bowen Brooke M. , Davis Emily M. , Dobbins Thomas , Barker Samantha N. , Legako Jerrad F. , Petry Amy L. , Carroll Jeffery A. 

TITLE=Evaluation of the use of prenatal immune stimulation to alter postnatal immune function in weaned pigs

JOURNAL=Frontiers in Animal Science

VOLUME=5

YEAR=2024

URL=https://www.frontiersin.org/journals/animal-science/articles/10.3389/fanim.2024.1418557

DOI=10.3389/fanim.2024.1418557

ISSN=2673-6225

ABSTRACT=<p>This study was designed to determine whether exposure to low-dose endotoxin (lipopolysaccharide; LPS) during gestation can enhance immunity to a subsequent LPS challenge in piglets after weaning. Pregnant sows (parity: 2.6 ± 1.4) were assigned to prenatal immune stimulation (PIS; <italic>n</italic> = 7; administered 2.5 µg/kg BW LPS, i.m.) or saline treatment groups (CON; <italic>n</italic> = 7) administered at day 78 ± 1.8 of gestation. From the two prenatal treatment groups, barrows (<italic>n</italic> = 17 PIS, 17 CON) were identified at weaning (21 ± 1.3 day of age) to subsequently receive a post-weaning LPS challenge. On day −1, the pigs were fitted with indwelling jugular catheters and subcutaneous temperature loggers. On day 0, the pigs were challenged i.v. with LPS (10 µg/kg BW), and blood samples were collected at −2, 0, 1, 2, 4, 6, 8, 12, and 24 h relative to LPS challenge. There was a treatment × time interaction for subcutaneous temperature (<italic>P</italic> &lt; 0.01), where the temperature increased more quickly at 1 and 2 h post-challenge in PIS compared to CON pigs. There was a tendency (<italic>P</italic> = 0.08) for less change in white blood cells, relative to baseline values, in PIS compared to CON pigs. There was a treatment × time interaction (<italic>P</italic> = 0.01) for lymphocyte concentrations where the concentrations were reduced in PIS compared to CON pigs at 8 h post-challenge. There was also a treatment × time interaction (<italic>P</italic> = 0.01) for the change in eosinophil concentrations, where there was less change in eosinophil concentrations from 1 to 12 h in PIS compared to CON pigs. There was a tendency (<italic>P</italic> ≤ 0.06) for a treatment × time interaction for serum interleukin-6 (IL-6) and IL-8. Granulocyte-macrophage colony-stimulating factor tended to be greater, and tumor necrosis factor-α tended to be reduced in PIS compared to CON pigs (<italic>P</italic> ≤ 0.08). These data suggest that exposure to endotoxin <italic>in utero</italic> may influence the postnatal innate immune response to endotoxin. More research is necessary to further understand the mechanism behind the differences observed and the potential long-term influence of prenatal immune stimulation on pig offspring.</p>