Bovine alloreactive cytotoxic cells generated in vitro detect BoLA w6 subgroups

Area of Science:

• Immunology
• Veterinary Science
• Genetics

Background:

• Bovine leukocyte antigen (BoLA) class I molecules play a crucial role in immune responses.
• Understanding T cell recognition of BoLA specificities is vital for transplantation and disease resistance.

Purpose of the Study:

• To generate and characterize alloreactive cytotoxic T lymphocytes (CTL) against specific BoLA w6 subgroups.
• To investigate the influence of in vivo priming on CTL generation.

Main Methods:

• Mixed lymphocyte cultures were used to generate CTL against BoLA w6 subgroups.
• Restimulation and weekly testing in 51Cr-release assays with Theileria annulata-infected target cells.
• In vivo priming through skin grafting was employed to assess its effect on CTL generation.

Main Results:

• CTL specific for BoLA w6 subgroups (w6.1, w6.2, w6.3, w6.4) were successfully generated.
• CTL generation was accelerated in animals primed with skin grafts.
• Significant CTL activity was observed, particularly against w6.2, w6.3, and w6.4 (p<0.1%).
• When targeting heterozygous cells, similar CTL activity was seen against both BoLA products in w6.4/w16 and w6.1/w4 combinations.
• Higher CTL activity was directed against w10 than w6 subgroups in w10/w6.1 or w10/w6.2 combinations.

Conclusions:

• Specific CTL responses against BoLA w6 subgroups can be reliably generated.
• In vivo priming enhances CTL generation kinetics.
• BoLA-A locus products exhibit differential T cell recognition, with some specificities being more immunodominant than others.