Since CD18 is ubiquitously expressed on leukocytes and is involved in adhesion and extravasation54,55, our tumor FACS and histology data suggest that T cell recruitment is unimpeded in the collagen-rich tumor microenvironment, consistent with observations from prior studies56–58, but in contrast to findings which suggest that collagen mechanically hinders T cell infiltration18,59,60. The gene discussed is ITGB2; the disease is neoplasm.