CD antigen CD98 is also known as 4F2 cell-surface antigen heavy chain (4F2hc), 4F2 heavy chain antigen, Solute carrier family 3 member 2 (SLC3A2), Lymphocyte activation antigen 4F2 large subunit, is a single-pass type I I membrane protein which belongs to the SLC3A transporter family.. SLC3A2 / CD98 is expressed ubiquitously in all tissues tested with highest levels detected in kidney, placenta and testis and weakest level in thymus. SLC3A2 / CD98 is required for the function of light chain amino-acid transporters and also involved in sodium-independent, high-affinity transport of large neutral amino acids such as phenylalanine, tyrosine, leucine, arginine and tryptophan. CD98 involved in guiding and targeting of LAT1 and LAT2 to the plasma membrane. When associated with SLC7A5 or SLC7A8, CD98 involved in the cellular activity of small molecular weight nitrosothiols, via the stereoselective transport of L-nitrosocysteine (L-CNSO) across the transmembrane. Together with ICAM1, regulates the transport activity LAT2 in polarized intestinal cells, by generating and delivering intracellular signals.