CD2 costimulation as a method to improve mouse T cell activation by soluble antibody complexes

Abstract

Listen

Translate article

Abstract Immunology research using mouse T cells requires cell activation that is often achieved using anti-CD3/CD28 antibodies immobilized (imm) on beads or cultureware. This immobilization can be tedious, leading us to investigate mouse T cell activation using soluble (sol) antibody complexes. Purified mouse T cells were activated by immCD3/CD28 or solCD3/CD28 complexes for 2 days, resulting in an average of 85% and 68% CD25+ T cells by flow cytometry, respectively (n = 12). However, adding CD2 to the solCD3/CD28 complex increased the %CD25+ T cells to 99% after 2 days (n = 12), suggesting that CD2 enhances activation. Purified T cells activated by solCD3/CD28/CD2 complexes showed improved fold expansion (28-fold) after 7 - 8 days compared to activation by immCD3/CD28 (15-fold) or solCD3/CD28 (18-fold) complexes (n = 17). As well, purified CD4+ T cells activated by solCD3/CD28 complexes exhibited increased fold expansion from 1- to 20-fold after 8 days by adding CD2 to the complexes (n = 3). Lastly, we investigated how activation methods impact a 6-day polarization of naive CD4+ T cells to T helper subsets. Cells activated by solCD3/CD28 complexes resulted in 53% Th1, 29% Th2, or 67% Treg cells, whereas solCD3/CD28/CD2 complexes resulted in 77% Th1, 24% Th2, or 79% Treg cells (n = 6). In summary, these soluble ImmunoCult™ Mouse T Cell Activators effectively activate, expand, and polarize mouse T cell subsets, which is enhanced by CD2 costimulation.