Dietary supplementation with spray-dried animal plasma improves vaccine protection in aged mice.

BACKGROUND

Senescence is characterized by an aggravated inflammatory state that reduces vaccine responsiveness. Dietary supplementation with spray-dried porcine plasma (SDP) exerts anti-inflammatory effects in different mucosal areas. We aimed to determine if the anti-inflammatory properties of SDP improve the efficiency of immunization in senescent animals.

METHODS

Experiments were performed in 2-month-old and 6-month-old male SAMP8 mice fed control or SDP (8%) feeds for 4  months. The mice received nasal doses of 2.5  μg of enterotoxin B (SEB) or vehicle every 15  days (i.e., 3 times). Fifteen days after the last dose, a lethal shock was induced by intraperitoneal administration of SEB and LPS.

RESULTS

Immunization increased anti-SEB IgA in intestinal and bronchoalveolar fluid ( < 0.05). After the lethal shock, all immunized aged mice that were supplemented with SDP survived, in contrast to only 66% of those fed the control feed ( < 0.05). Moreover, after the lethal challenge, aged mice showed higher expression levels of pro-inflammatory cytokines (, , , and ) in jejunal and (, and ) in lung tissues ( < 0.05), which were reduced by SDP supplementation ( < 0.05). Furthermore, in senescent mice, SDP supplementation augmented and expression in both tissues ( < 0.05).

CONCLUSION

SDP reduces the mucosal inflammation associated with aging, improving vaccine protection in senescent mice.