TNF and primary hypophysitis: Moreover, suppression of hypophysitis was observed when the tumor necrosis factor (TNF)-α pathway was blocked locally, at the site of immunization, and not systemically, by the administration of emulsified placental proteins, providing evidence that the placenta contributes to the immune tolerance of pregnancy by locally inhibiting the TNF-α pathway, reproducing the relationship between autoimmune hypophysitis and pregnancy [12].