Cell-mediated immunity against turkey coronaviral enteritis (bluecomb).

Studies on cell-mediated immune response in turkeys infected with turkey coronavirus (TCV) were made. A whole blood culture technique was developed for quantitatively evaluating in vitro lymphocyte reactivity to mitogens concanavalin A, phytohemagglutinin-P, and TCV antigen. The degree of blastogenesis was quantitated by the measurement of the uptake of the [125I]deoxyuridine in the presence of fluorodeoxyuridine. The stimulation indices were consistently higher in the infected birds compared with those in the noninfected controls, and they were statistically significant (P < 0.05). The detection of TCV specific responses indicated that cell-mediated immunity may be important in determining the immunity against turkey coronaviral enteritis. The whole blood lymphocyte transformation assay was emphasized as a convenient and useful in vitro indicator of cell-mediated immunity in TCV infection.