Antigens uptake

Apple, R.J., Domen, P.L., Muckerheide, A., and Michael, J.C. (1988) Cationization of protein antigens. IV. Increased antigen uptake by antigen-presenting cells./. Immunol. 140, 3290-3295. 

Lanzavechia, A. (1990). Receptor-mediated antigen uptake and its effect on antigen presentation to class-II restricted T-lymphocytes. Ann. Rev. Immunol., 8, 773-793. 

These MALT are structurally and functionally divided into two sites - the inductive sites for antigen uptake and processing on the one hand, and the effector sites engaging lymphocytes/plasma cells, granulocytes and mast cells, on the other hand. 

Simionescu N (1983) Cellular aspects of transcapillary exchange. Physiol Rev 63 1536-1579 Simons K, Ikonen E (1997) Functional rafts in cell membranes. Nature 387 569-572 Snoeck V, Goddeeris B, Cox E (2005) The role of enterocytes in the intestinal barrier function and antigen uptake. Microbes Infect 7 997-1004 Sugiyama Y, Kato Y (1994) Pharmacokinetic aspects of peptide delivery and targeting importance of receptor-mediated endocytosis. Drug Dev Ind Pharm 20 591-614 Takano M, Yumoto R, Murakami T (2006) Expression and function of efflux transporters in the intestine. Pharmacol Therap 109 137-161... 

The uptake of antigen by M cells is believed to be an important process for the development of mucosal immunity. The ability to develop vaccines that target M cells to enhance antigen uptake would therefore increase the likelihood that an effective immune response could be elicited. 

Increasing the uptake of antigens by enterocytes may represent an alternative means for oral vaccine delivery. It is, however, commonly believed that antigen uptake by enterocytes leads to the production of antigen tolerance rather than immunity (Brayden and Baird 2001). 

Association of an antigen with an appropriate microparticulate carrier may enhance antigen uptake by vaginal antigen-presenting cells. This strategy for vaginal vaccine delivery is described below (Section 11.7.5). 

The BCR mediates antigen uptake for processing and presentation of the antigeiuc peptide-MHC class II complex to T cells. 

Fig. 4. Percent uptake of different iiposomai formuiations conjugated to Rtiodamine by human DCs measured through flow cytometry. Ceiis were incubated with Rhodamine-MSP-1, g-ioaded iiposomai formuiations and anaiyzed at different time intervals (0,15,30,60,120,180, and 360 min). The kinetics of uptake has been presented with mean fluorescence intensity (MFI) vs. counts by FACS analysis and percentage uptake at various time inten/als. Uptake of formulation on a per cell basis was quantified as fluorescence intensity per cell. Percentage of positive cells was determined as proportion ot cells with fluorescence intensity higher than 99% of cells of the control sample (cells incubated with unconjugated rhodamine alone). Flow cytometric analysis revealed that the percentage of rhodamine-positive DCs increased rapidly and reached a plateau after 16 h of incubation (means of three independent experiments). A steady increase in the uptake percentage (%) was recorded and a maximum cell-associated fluorescence was observed at 16 h for OPM-coated cationic liposomes. Flow cytometric analysis of DCs revealed that plain liposomes did not significantly enhance the antigen uptake by DCs compared with the uptake recorded for mannan-coated liposomes...

A. Cambi, D. S. Lidke, D. J. Amdt-Jovin, C. G. Figdor, and T. M. Jovin, Ligand-conjugated quantum dots monitor antigen uptake and processing by dendritie cells, Nano Lett., 7 (2007) 970-977. 

Cambi A, Gijzcn K, de Vries JM et al. The C-type lectin DC-SIGN (CD209) is an antigen-uptake receptor for Candida albicans on dendritic cells. Eur J Immunol 2003 33 532-538. 

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