Table 1.

Class II major histocompatibility complex (MHC) proteins used in MHC tetramer staining of antigen-specific CD4⁺ T cells

Species	MHC protein	Allotype	Expression system	Modification	References
Human	DR1	DRB1*0101	Escherichia coli	–	5
			E. coli	Covalent peptide	15
			Insect	–	5
			Insect	Zipper	54
			Mammalian	Covalent and zipper	30
	DR2	DRB1*1501	Mammalian	Covalent and zipper	30
		DRB5*0101	Mammalian	Covalent and zipper	30
	DR3	DRB1*0301	Insect	Zipper	45
	DR4	DRB1*0401	Insect	Covalent peptide	3,64
			Insect	Zipper	53
			Mammalian	Covalent and zipper	30
		DRB1*0402	Insect	–	83
		DRB1*0404	Mammalian	–	84
	DR5	DRB1*1101	E. coli	Covalent peptide	15
			Insect	Zipper	85
	DR6	DRB1*1302	Insect	Zipper	86
	DR7	DRB1*0701	Insect	Zipper	54
	DQ6	DQA1*0102 DQB1*0602	Insect	Zipper	87
	DQ2	DQA1*0501 DQB1*0201	Insect	Zipper	88
	DP4	DPA1*0103 DPB1*0401	Insect	Covalent and zipper/Ig	49,89
Mouse	I-E	I-E(k)	E. coli	–	11
			Insect	Covalent and zipper/Ig	2,25
			Mammalian	–	11
		I-Edk	Insect	Covalent peptide	24
	I-A	I-Ad	Insect	Covalent and zipper	24
		I-Ab	Insect	Covalent and zipper	65,78
		I-Au	Insect	Covalent and zipper	90
		I-Ag7	Insect	Covalent and zipper/Ig	25,91
		I-As	Insect	Covalent and zipper	92
		I-Aq	Insect	Covalent and zipper	90
Chicken	B-L	B21	Insect	Zipper	93
		B19	Insect	Zipper	93
Cow	BoLA	DRB3*1101	Mammalian	Covalent and zipper	94
		DRB3*1201	Mammalian	Covalent and zipper	94
Rat	RT1.B	β1α1	E. coli	Single chain	95
Monkey	Mamu-DR	DRB*W201	Insect	Covalent peptide	96