Then, we investigated the possible mediator(s) by which B-1 lymphocytes promote the formation of granuloma-like structures and found that adding B-1 (and not B-2) lymphocytes to M2 macrophages further increased the levels of tissue inhibitor metalloproteinase 1 (TIMP-1) when exposed to granuloma-inducing CNT (Fig. 5c). The gene discussed is TIMP1; the disease is Granuloma.