Up to now, 15 members have been identified in CTRP superfamily (CTRP1–CTRP15).
The C1Q/TNF-related protein (CTRP) family, usually contains a homotrimeric structure, which comprises the N-terminal signal peptide and the C-terminal C1q globular domain. It has been demonstrated that CTRPs play pivotal roles in the inflammation process. CTRP4 is a member of the CTRP family and contains two C1q globular domains. Moreover, evidence shows that the recombinant human CTRP4 (rhCTRP4) protein exerts satisfactory anti-inflammatory effects in experimental colitis models via the NF-κB pathway.
Findings suggest that CTRP4 is highly expressed in herpes simplex encephalitis and is closely related to the progression of HSE. Thus, CTRP4 may serve as a potential severity index for HSE and targeting CTRP4 might be a promising therapeutic strategy against HSE 1).