Monitoring responses by use of five-color flow cytometry in subsets of peripheral T cells obtained from cattle inoculated with a killed Mycobacterium avium subsp paratuberculosis vaccine.
OBJECTIVE
To monitor by use of 5-color flow cytometry the antigen-specific responses of subsets of peripheral T cells in cattle inoculated with a killed Mycobacterium avium subsp paratuberculosis (MAP) vaccine and to compare results with those for 2 established cell-mediated immunity assays.


METHODS
45 female Holstein cattle with negative results for MAP in skin tests conducted at time of inoculation with MAP.


METHODS
Cattle were allocated to 4 groups. Cattle of group 1 (n = 12) were 0 to 3 months old and inoculated with a killed MAP vaccine. The 10 cattle of group 2 were the same age as those in group 1 but were not inoculated with MAP vaccine. The 11 cattle of group 3 were 9 to 12 months old and inoculated with killed MAP vaccine. The 12 cattle of group 4 were the same age as those in group 3 but were not inoculated with MAP vaccine.


RESULTS
Flow cytometry identified T-cell subsets that responded specifically to the recall antigen. Results of assays for CD25 expression and wholeblood interferon-gamma had the strongest correlation with results for skin tests as well as results with each other. Intracellular expression of interferon-gamma was not correlated as well with results for the other tests.


CONCLUSIONS
Flow cytometry can be useful for characterizing the immune response after administration of MAP vaccine and should be evaluated with regard to its sensitivity and specificity when used in detecting cattle naturally infected with MAP.
Platt
Ratree
R
Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA.
Roth
James A
JA
Royer
Ryan L
RL
Thoen
Charles O
CO
D000818:Animals; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000276:immunology*; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D005434:Flow Cytometry / Q000379:methods / Q000662:veterinary*; D007371:Interferon-gamma / Q000097:blood; D016927:Mycobacterium avium subsp. paratuberculosis / Q000276:immunology*; D010283:Paratuberculosis / Q000276:immunology*; D012882:Skin Tests / Q000662:veterinary; D013223:Statistics as Topic; D013601:T-Lymphocytes / Q000276:immunology*; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000276:immunology
D001428:Bacterial Vaccines; D015164:Vaccines, Inactivated; D007371:Interferon-gamma