interfacial epithelial cell rectal epithelial cell WBbt:0008182 worm_anatomy These cells include: B, F, Y, U, K' and K. All rectal epithelial cells contain secretory membrane stacks along this region facing the lumenal cuticle and produce some portion of the cuticular lining of the rectum. These are interfacial cells that connect the alimentary system to the main body syncytium. rectal epithelium