TNF and abortion: However, in the CBA×DBA/2 model, increased expression of Th1-type cytokines such as interleukin (IL)-1, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α, and decreased expression of Th2-type cytokines such as transforming growth factor (TGF)-β2, IL-4, and IL-10 are responsible for the spontaneous abortion [15], [22]–[24].