Natural Killer Cells and Their Role in Rheumatoid Arthritis: Friend or Foe?

Table 1

NK cell receptors can be divided in two groups based on binding to MHC class I- or non MHC class I molecules as their ligands. NK cell receptors can also be structurally divided in two groups as immunoglobulin superfamily or killer cell lectin-like receptors.

NK cell receptors
MHC-I binding receptors		Non MHC-I binding receptors
	Species		Species
Ly49 family	Mouse	Ly49 family	Mouse
KIR family	Human	NKR-P1 family	Human and mouse
CD94/NKG2 family	Human and mouse	NCR family	Human and mouse
		NKG2D family	Human and mouse
Immunoglobulin superfamily receptors		Killer cell lectin-like receptors
KIR family		Ly49 family
NCR family		NKR-P1 family
FcγRIII, 2B4, DNAM-1		NKG2D family, CD94/NKG2 family