Participation of Semaphorin Family and Plexins in the Clinical Course of Patients with Inflammatory Bowel Disease.

UNLABELLED: Semaphorins are an immunoregulatory protein family. Plexins bind semaphorins (SEMAs) and can form receptor complexes that give them chemotactic capacity. The role and expression profile of semaphorins and plexins in inflammatory bowel disease (IBD) is currently unknown.

AIM: Characterize the semaphorins and plexins gene and protein expression in intestinal tissue from IBD patients and correlate them with the clinical phenotype.

MATERIAL AND

METHODS

This comparative and cross-sectional study enrolled 54 diagnosed IBD patients and 20 controls. Gene and protein expression of semaphorins and plexins were determined by RT-PCR and IHQ for the co-localization with neutrophils (myeloperoxidase, MPO) or CD123 plasmacytoid dendritic cells in intestinal tissue from IBD patients.

RESULTS

Colonic mucosa from active and remission ulcerative colitis (UC) had a significantly lower SEMA4D and PLXNA1, but higher PLXNB1 gene expression than the control group. The only significant difference between active UC and remission was observed in the higher gene expression of SEMA6D in remission. It was associated with histological remission (p = 0.01, OR = 15, 95% CI: 1.39-16.1). The low expression of PLXNA1 was associated with mild intermittent activity with two relapses per year (p = 0.003, OR = 0.05, CI = 0.006-0.51). Higher SEMA4D+ positive cells were detected in the submucosa, while PLXNC1+/MPO+ in the mucosal and submucosa of active UC patients compared with controls.

CONCLUSIONS

The increased expression of the semaphorin and plexin family in IBD patients suggests their immunoregulatory function and is associated with remission and clinical phenotype in patients with UC.