OJI  Vol.2 No.2 , June 2012
α2-macroglobulin co-administered in vivo promotes antigen delivery and presentation
Abstract: Administered in vivo, covalent receptor-recognized α2-macroglobulin (α2M*)-antigen complexes enhance humoral and cell-mediated immunity. We hypothesized that in vivo α2M*-encapsulation could be promoted in the setting of vaccines that co-deliver α2M* with unbound antigen, thereby eliminating the need to prepare complexes in vitro. Mice immunized intradermally with co-delivered α2M* and OVA demonstrated antigen-specific immune responses, including anti-tumor responses, similar to those elicited by conjugated α2M*-OVA complexes. Enhanced immunity appears to result from in vivo α2M*-encapsulation of antigen. This finding represents a significant advancement in the development of α2M* as an antigen delivery vehicle capable of enhancing the presentation of subunit vaccines.
Cite this paper: Bowers, E. , Bond, J. , Cianciolo, G. and Pizzo, S. (2012) α2-macroglobulin co-administered in vivo promotes antigen delivery and presentation. Open Journal of Immunology, 2, 72-77. doi: 10.4236/oji.2012.22009.

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