Assessment of T-dependent and T-independent immune responses in cattle using a B cell ELISPOT assay.
Understanding the mechanisms that maintain protective antibody levels after immunisation is important for vaccine design. In this study, we have determined the kinetics of plasma and memory B cells detectable in the blood of cattle immunised with model T-dependent or T-independent antigens. Immunisation with the T-D antigen resulted in an expansion of TNP-specific plasma cells post-TNP primary and booster immunisations, which was associated with increased titres of TNP-specific IgG antibodies. Although no TNP-specific memory B cells were detected in the T-D group following the primary immunisation, we detected an increase in the number of TNP-specific memory B cells post-TNP boost. In contrast, no TNP-specific plasma or memory B cells were detected after primary or secondary immunisation with the T-I antigen. We then investigated if immunisation with a third party antigen (tetanus toxin fragment C, TTC) would result in a bystander stimulation and increase the number of TNP-specific plasma and memory B cells in the T-D and/or T-I group. TTC immunisation in the T-D group resulted in a small increase in the number of TNP-specific plasma cells post-TTC primary immunisation and boost, and in an increase in the number of TNP-specific memory B cells post-TTC boost. This bystander effect was not observed in the animals previously immunised with the T-I antigen. In conclusion, the present study characterised for the first time the B cell response in cattle to immunisation with T-D and T-I antigens and showed that bystander stimulation of an established T-D B cell memory response may occur in cattle.
Institute for Animal Health, Compton Laboratory, High Street, Compton, Berkshire, RG20 7NN, United Kingdom. bryan.charleston@iah.ac.uk.
Clare Fj
CF
Grant
Eric A
EA
Lefevre
B Veronica
BV
Carr
Helen
H
Prentice
Simon
S
Gubbins
Andrew J
AJ
Pollard
Catherine
C
Charreyre
Bryan
B
Charleston
D000818:Animals; D000906:Antibodies / Q000097:blood; D000941:Antigens / Q000097:blood; D001402:B-Lymphocytes / Q000276:immunology*; D002417:Cattle / Q000097:blood / Q000276:immunology*; D058501:Enzyme-Linked Immunospot Assay / Q000662:veterinary; D005362:Ficoll / Q000031:analogs & derivatives / Q000276:immunology; D006241:Haptens / Q000276:immunology; D007118:Immunoassay / Q000662:veterinary; D007156:Immunologic Memory; D007963:Leukocytes, Mononuclear / Q000502:physiology; D008297:Male; D010950:Plasma Cells / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014301:Trinitrobenzenes / Q000276:immunology; D005719:gamma-Globulins / Q000276:immunology
D000906:Antibodies; D000941:Antigens; D006241:Haptens; C026595:TNP-AECM-ficoll; D014301:Trinitrobenzenes; D005719:gamma-Globulins; D005362:Ficoll