TABLE 2.

Mutated residues in vIL-6

Position(s)	Residue(s)	Change(s)	Mutant designation	Activity	Comments	Reference(s)
13	G	W	1	+++	Conserved
41, 43	W, L	F, G	19	+++	Site II, gp130 interactions (hIL-6)	50, 52
54	C	D	2	+++	Conserved
		G	3	+++
60	C	S	4	+++	Conserved
		L	5	+++
75	P	S	7	+++	Conserved
83	C	G	8	+++	Conserved, functional (hIL-6)	46, 57
88	F	L	20	+++	Site I, important for IL-6R binding (hIL-6)	59
93	C	G	9	+++	Site I, conserved, functional (hIL-6)	46, 57
		W	10	+++
103–105	EFE	EGG	22	+++	Site I, E-103 conserved, important for IL-6R binding (hIL-6)	59
		GVA	23	+++
129	T	L	11	+++	Site II, conserved
		A	12	+++
151	P	F	13	+++	Conserved
		S	14	+++
167	W	G	15	+	Site III, conserved
		R	16	+++
167, 172	W, A	R, P	24	+	Site III, required for hexameric (functional) complex formation	13
183	F	W	17	+++	Conserved, F to A in hIL-6 shows reduced cell surface binding	31
		G	18	+++
		E	29	+++
		L	31	+++
189	R	L S C	25 26 27	+++ +++ +++	Site I, conserved, positively charged residue at this position in hIL-6 important for binding and activity	20, 31
195	P	Stop	28	+++	C-tail deletion, 195–204