This is the concept of immunoendocrinology.A pratical example is the interaction between pineal gland(endocrine gland) and immune system. Pineal gland secrets melatonin.(hormone that regulate sleep-wake cycle) ,
Evidence has shown that interleukin 1 beta inhibits secretion of melatonin by the pineal gland through suppression of arylalkylamine-N-acetyltransferase (AA-NAT) protein expression which lead to inhibition of melatonin secretion.
The activities of small non coding RNA molecules-Micro-RNAs in exerting effects on the biological process at different levels is another example. These RNAs have effects on the autoimmune diabetes.
Specifically Micro-RNAs exerts functional regulatory effects at cells,tissues, organs levels between the pancreatic beta cells and the immune systems. Thus the interaction provided by these RNA plays a major role in understanding the effects of relationship between the immune systems and beta cells of the pancreas for autoimmune diabetes