FIG. 2.

Depletion of naive CD4⁺ T lymphocytes (CD4⁺ CD45R⁺ T lymphocytes). Mean percentages (± standard errors of the means) of CD4⁺ CD45R⁺ T lymphocytes in blood, spleen, or lymph nodes of thymectomized calves treated with a subclass-matched control MAb (•) or thymectomized calves treated with anti-CD4 MAb (▾). The arrows indicate the day of infection for each experiment (experiment 1, day 5 following the commencement of MAb treatment; and experiment 2, day 12 following the commencement of MAb treatment).