Table 2.

Immunomodulating agents applied to xenotransplantation.

Sources	Immunomodulating Agents	Component Mechanism	Pig-to-NHP Xenotransplantation	Reference
Under investigation	Anti-CD154 Ab	Blockade of CD40−CD154	Kidney, heart, islets	[145,146,147]
	Cobra venom factor	Inhibition of complement system	Islets	[34]
	Anti-CD40 Ab	Blockade of CD40−CD154 costimulatory signal	Kidney, heart, islets	[145,147,148]
FDA non-approved, commercially available	Eculizumab	Blockade of the C5b-9 MAC	Pancreas	[149]
	Etanercept	Anti-TNF-alpha inhibitor	Islets	[150]
	Intravenous immunoglobulin	Modulating antigen presenting cell activity and complement activation	Hearts	[151,152]
	IL-1 receptor antagonist	IL-1 inhibitor	Heart	[153]
	IL-6 receptor antagonist	IL-6 inhibitor	Islet, Kidney, Heart	[154,155]
FDA approved for transplantation	Tacrolimus	Inhibition of the enzyme calcineurin by binding of FKBP-12	Pancreas	[156,157]
	Mycophenolic acids	Inhibition of the lymphocyte cycle by blocking inosine monophosphate dehydrogenase	Kidney, heart, islets	[158,159]

Abbreviation: Ab, antibody; NHP, non-human primate; MAC, membrane attack complex; TNF, tumor necrosis factor; IL, interleukin; FDA, the Food and Drug Administration.