Submitted to: Veterinary Immunology and Immunopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/12/1997
Publication Date: N/A
Interpretive Summary: The Second International Swine CD Workshop was organized under the auspices of the International Union of Immunological Scientists. It enabled scientists worldwide to independently verify the reactivity of panels of monoclonal antibodies (mAbs) reactive with pig immune cells and, thus, to precisely identify important new mAb reagents to aid analyses of swine disease and vaccine responses. Of the 195 mAb tested during the workshop 57 were tested for reactivity with T cells and, as a result of the second round analyses for T cell specificity, 23 were designated as reactive with defined pig T cell CD antigens: 2 wCD2, 6 CD3, 1 wCD4, 2 wCD5, 1 wCD6, 3 wCD8 and 1 wCD25. It is notable that this workshop was successful in identifying a whole panel of anti-CD3 mAbs, a CD subset for which previously no mAb had been identified; 6 anti-CD3 mAb were defined in swine, 3 of which reacted with the CD3a epitope that when bound stimulated T cell proliferation. For many of the new T cell reactive mAb epitope mapping indicated that they recognized the same area (epitope) of the CD antigen as previously characterized mAb. Only for wCD8 were mAb that reacted with unique determinants of the wCD8 molecule defined. Firm characterization of mAb which recognize unique T cell determinants will enable scientists to clearly differentiate unique subsets of swine T cells and to assess fully the functions of these important lymphoid cell subpopulations as they define swine immune cell interactions.
Technical Abstract: After initial evaluation of the 176 new and 19 control monoclonal antibodies (mAb) submitted to the Second International Swine CD Workshop, 57 were assigned to the T-cell/activation marker subgroup. These 57 mAb were further analyzed using flow cytometry on whole blood lymphocytes, splenocytes, Peyer's patch lymphocytes, in vitro cell lines, broncho-alveolar lavage cells, Con A and PHA blasts, fetal cell populations, and by 2-color flow cytometry against mAb to porcine CD2, CD4, and CD8. Finally, the molecular weights of the target antigens were characterized when possible. As a result of these analyses, 23 mAb were distributed into 7 CD clusters. Newly confirmed mAb assignments included: two wCD2; one wCD4; two wCD5; one wCD6; and one wCD25. Three new mAb were found that reacted with wCD8, one of which defined a new epitope, wCD8c. For the first time, mAb against porcine CD3 were identified, including 6 mAb that reacted with three different epitopes. Several new mAb reacted with antigens whose expression varied depending on the activation state of the test cell. These will require further characterization in order to assign a CD number.