However, we initially noticed by using a p19-specific enzyme-linked immunosorbent assay (ELISA) that p19 is secreted into the culture supernatants from most of the mouse T cell hybridomas and lymphoma examined in response to stimulation with TCR ligation using anti-CD3, although the amounts secreted by the different cells varied (Fig. 1a). The gene discussed is IL23A; the disease is lymphoma.