Effect of interleukin-2 and interleukin-4 on lymphocytes from peribronchial lymphatic tissue

Lymphocyte activation in spleen and peribronchial lymphatic tissue (PBLT) following stimulation with T-cell mitogens and lymphokines was investigated in the hamster. Optimal mitogen-induced cell proliferation was achieved after culturing for 6 days in vitro. Interleukin-2 (IL-2) and interleukin-4 (IL-4) did not induce DNA synthesis in resting T-cells from either spleen or PBLT.IL-2 or IL-4 in combination with concanavalin A promoted splenic T-cell proliferation. In contrast, in PBLT, IL-2-but not IL-4-enhanced cell proliferation (p < .001). The findings indicate that PBLT represents an independent compartment of the immune system. Furthermore, in the hamster PBLT cells consist predominantly of IL-2-responsive cells, i.e., are of the Th1 type. Immunological pathogenesis of lung injury can therefore be studied by functional analysis of PBLT lymphocytes.