Positive Samples: U-937, Mouse thymus, Mouse lung, Rat thymus Immunogen sequence: QECTKFKVSS CRECIESGPG CTWCQKLNFT GPGDPDSIRC DTRPQLLMRG CAADDIMDPT SLAETQEDHN GGQKQLSPQK VTLYLRPGQA AAFNVTFRRA KGY. CD18, also known as the integrin beta 2 subunit, is a 90-