Immunoadsorption of alloantibodies onto erythroid membrane antigens encapsulated into polymeric microparticles.
OBJECTIVE
Classical immunoadsorbents used for the removal of deleterious molecules in blood such as auto-antibodies are prepared by covalent coupling of antigens onto previously chemically activated supports. Such a chemical treatment may induce a potential toxicity which can be reduced if new immunoadsorbents are prepared by encapsulating erythrocytes-ghosts carrying antigens inside polymeric and porous microparticles.


METHODS
Erythrocyte-ghosts obtained by hemolysis in hypotonic buffer were encapsulated into ethylcellulose microparticles by w/o/w emulsification. The porosity of microparticles was evaluated by mercury porosimetry. The adsorption ability of encapsulated antigens was evaluated by hemagglutination after contact in tube or elution in column with polyclonal antibody solutions or human blood-plasma.


RESULTS
The encapsulation process did not significantly alter the evaluated antigens since a significant decrease in anti-A (from 256 to 4) as well as anti-Kell (from 64 to 2) antibody titer has been observed in column after eight chromatographic runs (2 h). The higher the ghost concentration (total protein content of 6 mg/ml), the higher the adsorption capacity.


CONCLUSIONS
Encapsulation, currently used for drug delivery purposes, may consequently also be applied to the design of new immunoadsorbents as biomaterials.
Hoffart
Valérie
V
INSERM U734-EA 3452, Faculty of Pharmacy, Nancy, France.
Maincent
Philippe
P
Lamprecht
Alf
A
Latger-Cannard
Véronique
V
Regnault
Véronique
V
Merle
Christian
C
Jouan-Hureaux
Valérie
V
Lecompte
Thomas
T
Vigneron
Claude
C
Ubrich
Nathalie
N
D000017:ABO Blood-Group System / Q000276:immunology; D002482:Cellulose / Q000008:administration & dosage / Q000031:analogs & derivatives; D004910:Erythrocyte Membrane / Q000276:immunology*; D005434:Flow Cytometry; D006801:Humans; D007164:Immunosorbents / Q000008:administration & dosage*; D007518:Isoantibodies / Q000302:isolation & purification*; D007519:Isoantigens / Q000008:administration & dosage* / Q000276:immunology; D007626:Kell Blood-Group System / Q000276:immunology
D000017:ABO Blood-Group System; D007164:Immunosorbents; D007518:Isoantibodies; D007519:Isoantigens; D007626:Kell Blood-Group System; C013517:ethyl cellulose; D002482:Cellulose