sentences:  Tir, along with over 25 other bacterial proteins, is secreted from attaching and effacing "E. coli" directly into the cytoplasm of intestinal epithelial cells by a Type three secretion system.Once within the cytoplasm of the host cell, Tir is inserted into the plasma membrane, allowing surface exposure and intimin binding.Tir-intimin interaction mediates tight binding of enteropathogenic and enterohaemorrhagic "E.coli" to the intestinal epithelia, resulting in the formation of effacing lesions on intestinal epithelia.