Analysis of C3 and C4 in ovine plasma

Area of Science:

• Immunogenetics
• Veterinary Immunology
• Sheep Genetics

Background:

• Complement proteins C3 and C4 play crucial roles in immune responses.
• Understanding complement protein distribution and polymorphism in sheep is vital for disease resistance research.

Purpose of the Study:

• To investigate the plasma concentration distributions of complement proteins C3 and C4 in merino and Suffolk sheep.
• To explore potential correlations between complement protein levels and specific health conditions or breeding traits.
• To analyze the genetic variability of ovine C3 and C4 using electrophoretic methods.

Main Methods:

• Plasma samples from merino and Suffolk sheep were analyzed for C3 and C4 concentrations.
• Agarose gel electrophoresis and SDS-PAGE were employed to detect variants and heterogeneity in C3 and C4.
• Comparison of complement protein levels between different breeds, sexes, and health statuses.

Main Results:

• No significant differences in C3 and C4 concentrations were found between sheep breeds or sexes.
• Ovine C4 exhibited a polymodal and dispersed distribution compared to C3.
• Elevated C3 levels were observed in merino sheep bred as high responders to a Trichostrongylus vaccine.
• Decreased C4 concentrations were associated with congenital progressive ovine muscular dystrophy in merino and cross-bred sheep.
• Evidence for electrophoretic variants of ovine C4, but not C3, was found.
• SDS-PAGE revealed size heterogeneity in the alpha chain of ovine C4, suggesting isotypic/allotypic variability.

Conclusions:

• The study suggests the presence of two polymorphic C4 loci in sheep.
• Complement C3 and C4 levels may serve as indicators for specific immune responses and disease conditions in sheep.
• Genetic polymorphism in ovine C4 contributes to variability within the sheep complement system.