PCLAF and obesity due to melanocortin 4 receptor deficiency: Numerous studies have documented that BAFF can directly stimulate an increase in insulin resistance [33], providing a possible link between increased levels of inflammation, altered glycemic metabolism and weight gain by modulating the production of other inflammatory cytokines, such as TNF, IL-6 and PAF, and amplifying the signal between adipocytes and inflammatory cells that can lead to obesity [34].