Figure 8.

Impaired in vivo expansion of LCMV-GP–specific, TCR-transgenic, CD2-deficient T cells upon cross-priming. CD45.1⁺ TCR-transgenic control spleen cells were mixed 1:1 with CD45.1⁺ CD2-deficient spleen cells and adoptively transferred into C57BL/6 recipient mice. (A) Recipient mice were immunized with UV light–inactivated recombinant vaccinia virus expressing LCMV-GP, and spleen cells were analyzed 6 d later. CD45.1 expression was assessed for CD8⁺Vα2⁺ T cells, revealing expansion of CD2⁺ control T cells (upper right panels). CD2 expression was assessed similarly for CD8⁺ Vα2⁺ T cells, revealing expansion of CD2-deficient T cells (lower right panels). (B) Recipient mice were immunized with LCMV-GP associated with cellular debris, and spleen cells were analyzed 6 d later. CD45.1 expression was assessed for CD8⁺Vα2⁺ T cells, revealing expansion of CD2⁺ control T cells (upper right panels). CD2 expression was assessed similarly for CD8⁺Vα2⁺ T cells, revealing expansion of CD2-deficient T cells (lower right panels). Percentage of CD45.1⁺ control T cells versus CD2-deficient T cells was <3% in the absence of immunization. One representative experiment of two is shown.