Comparison of antibody and cell-mediated immune responses in horses following feeding of a novel dietary antigen, ovalbumin, and rotavirus.

The research article discusses a study that looks into how horses’ immune systems respond after being fed with ovalbumin and rotavirus. The findings suggest that when horses are fed the non-replicating protein antigen Ovalbumin, it may increase the immune response instead of inducing oral tolerance.

Research Methodology

• The researchers selected adult ponies for their experiment. These ponies were fed ovalbumin (OVA) daily for a period of two weeks.
• After this feeding period, the ponies were given an intramuscular injection with ovalbumin combined with saponin.
• A control group of ponies not given the fed antigen was also studied for comparison.
• Additionally, a separate group of ponies was challenged with equine rotavirus.

Findings

• The study found significantly greater serum anti-OVA IgG and antigen specific lymphocyte responses in the ponies after they received the intramuscular injection with OVA and saponin. This was in comparison to the control group that was not fed with the ovalbumin.
• The researchers note that there was no evidence of B- or T-cell activation in peripheral blood during the period of OVA feeding. However, the ponies seemed to be primed for an active secondary immune response, indicating that the feeding may implicitly stimulate the immune response.
• However, when the ponies were challenged with the equine rotavirus, there was no statistically significant difference found in their serum IgG-associated antibody responses or antigen-specific lymphocyte responses. This was true both after the rotavirus challenge and after receiving an intramuscular injection of rotavirus antigen with saponin.

Significance

• The important takeaway from the study is that feeding horses the non-replicating protein antigen Ovalbumin could potentially prime for an elevated immune response rather than inducing oral tolerance. This is seen by the immune response observed after intramuscular injection of the protein antigen.
• This is interesting since it may help with further understanding of how the equine gastrointestinal tract operates with typically harmless antigens.
• The lack of significant response in the case of the rotavirus may be due to the complex nature of the virus, which needs further study.