Similarly, accumulating evidence supporting the concept that immune dysregulation underlies depression, including anti-inflammatory effects of various antidepressants such as selective serotonin reuptake inhibitors [91], overall positive effects of non-steroidal anti-inflammatory drugs [92] or microglia inhibitor minocycline [93] led to testing other immunomodulatory treatments, such as methotrexate [94] or the TNF antagonist infliximab, showing positive results in subjects with drug-resistant depression [95]. Here, TNF is linked to major depressive disorder.