Table 1.

Specificity of human IgG subclasses for FcγR: + refers to affinity of binding of a subclass for the stated FcγR, – denotes that a subclass is reported not to bind to the stated FcγR [44]

	IgG1	IgG2	IgG3	IgG4
FcγRI (CD64)	+ + +	–	+ + +	+
FcγRII (CD32)
FcγRIIa-H131	+ +	+ +	+ + +	−
FcγRIIa-R131	+ +	–	+ + +	–
FcγRIIb	+ +	–	+ + +	+
FcγRIII (CD16)
FcγRIIIa	+ +	+	+ +	+
FcγRIIIb	+ +	+	+ +	–