Gene expression profile and cytokine analysis in experimental autoimmune encephalomyelitis (EAE) in AVP deficient rats

Introduction Human Multiple Sclerosis (MS) is a medically important disease. MS and its experimental autoimmune encephalomyelitis (EAE) paradigm are central nervous system demyelinizing diseases in which the immune system is directly involved. The pursuit for new treatments for MS still as an important goal for research. The use of the EAE animals to study the immune mechanisms that mediate the disease still being the best strategy to deep into the immune‐neuroendocrine interactions during the pathogenesis. Previously we have demonstrated that neurointermediate pituitary lobectomy (NIL) decreases humoral and cell‐mediated immune responses and that AVP is directly involved. Nevertheless, the role of AVP has not been entirely clarified. Objective To investigate the mechanism by which AVP deficiency (by NIL) and desmopressin (DP, a synthetic analog of AVP) affects the development of the clinical signs, the immune response and gene expression profile in the EAE. Methods Female Lewis rats were divided into intact control (IC), EAE immunized, NIL and NIL treated with desmopressin (NIL+DP). Except the IC, the remaining groups were immunized for EAE. The EAE was induced by encephalitogen subcutaneous injection. Animals were sacrificed at the peak of the disease (15 days after immunization). EAE clinical signs, cytokine serum profiles (IL‐17A, IL‐4, IL‐2, IL‐10, IL‐6, TNF‐α and INF‐γ) (flow cytometry) and spleen gene expression profile (microarray) were evaluated. DP treatment started 3 days before immunization. Results As compared with the EAE group, NIL animals developed just a mild clinical signs of EAE and significant decreased IFN‐γ and IL‐17 levels. NIL+DP treated animals restored its susceptibility to EAE clinical signs, whereas no‐significant differences on cytokine levels occurred. Significant differences in gene expression profile among groups were evident; in the NIL group the expression pattern of the TGF‐β pathway was down‐regulated as compared with the EAE group, whereas in the NIL+DP group the same genes were up‐regulated. Conclusions Findings add novel data indicating that directly AVP plays a crucial role in regulating the immune responses and suggests that AVP receptor blockers may be used for the MS treatment and possibly autoimmune diseases and other inflammatory processes. Support or Funding Information Supported by UAA‐PIFF14‐1 and CONACYT‐221262 (AQS). México. VVB: CONACT Doctoral scholarship. NMS: CONACYT post doctoral Fellow. México. This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .