Factors associated with adverse reactions induced by caprylic acid-fractionated whole IgG preparations: comparison between horse, sheep and camel IgGs.

The research article investigates the factors responsible for adverse reactions caused by whole IgG preparations fractionated by caprylic acid. It compares these reactions between IgGs from horses, sheep, and camels, concluding that camel IgG had the least potential for triggering adverse reactions.

Summary of Research

• The scientists have explored caprylic acid purification of IgG, concentrating primarily on horse-derived antivenoms. They expanded this method to include sheep and camel IgG. This process revealed different molecular masses for the IgG of each animal: approximately 150 kDa for sheep and two bands of approximately 160 and 100 kDa for camel – the second of which is a heavy-chain IgG lacking light chains.
• The IgG examples from the three different animal sources were evaluated to predict their potential to provoke early and late adverse reactions. The IgGs of horses and sheep demonstrated higher anticomplementary activities than camel IgG. They also generated a stronger anti-IgG response when injected into mice.

Findings

• Analysis showed that horse IgG agglutinated type O+ human erythrocytes. In contrast, no such reactivity was noted in the IgG preparations from sheep or camels.
• The study also introduced a new procedure to identify antibodies in human serum that react against animal IgGs. On testing a pooled human sera sample collected in Costa Rica, researchers found a higher level of antibodies targeted against horse and sheep IgGs when compared to camel IgG.
• The overall results indicated that camel IgG was least likely to induce adverse reactions as compared to IgGs from horses and sheep.

Conclusions

• The research indicates that caprylic acid-purified IgGs from different animal sources can lead to varying degrees of immune reactions.
• The method to purify IgG seems to work consistently across different species. This could have implications for the production of antivenoms.
• The research suggests that camel IgG has the least potential to cause adverse reactions, potentially making it a better source for IgG to produce antivenom therapeutics. However, further research would be necessary to confirm this.