Antigen-specific T cell proliferation following coccidia infection

Area of Science:

• Immunology
• Veterinary Science
• Parasitology

Background:

• Coccidiosis, caused by Eimeria species, is a significant poultry disease.
• Understanding the host immune response, particularly T lymphocyte proliferation, is crucial for developing effective control strategies.

Purpose of the Study:

• To investigate coccidia antigen-specific T lymphocyte proliferation in chickens following Eimeria acervulina infection.
• To compare immune responses in congenic and unrelated chicken lines.

Main Methods:

• Measurement of T lymphocyte proliferation in response to Eimeria acervulina antigens (sporozoites and merozoites).
• Analysis of immune responses in chickens congenic at the major histocompatibility complex and in two unrelated lines.
• Comparison of splenic and peripheral blood lymphocytes.

Main Results:

• Both sporozoites and merozoites induced high lymphocyte proliferation after primary infection.
• Line 15I5 exhibited the highest antigen-specific proliferation after primary and secondary infections.
• Merozoites generally elicited stronger proliferation responses than sporozoites.
• Lymphocyte proliferation varied between infected and uninfected chickens throughout the infection cycle.

Conclusions:

• Eimeria acervulina infection effectively induces coccidia antigen-specific T lymphocyte proliferation in chickens.
• Genetic background, particularly the major histocompatibility complex, influences the magnitude of the T lymphocyte response.
• Chicken lines differ in their capacity to mount proliferative T cell responses to coccidia antigens.