BIOENCAPSULATION 

Minerva Biotecnologica 2000 December;12(4):235-40

Copyright © 2000 EDIZIONI MINERVA MEDICA

lingua: Inglese

Preliminary research on biocompatibility of alginate-chitosan-polyethyleneglycol microcapsules

Lou W., Qin X., Wu Z.

Department of General Surgery, Zhongshan Hospital, Fu Dan University Medical Center, Shanghai, China

Background. To com­pare the bio­com­pat­ibil­ity of the algi­nate-poly­ly­sine-algi­nate (APA) micro­cap­sule and the algi­nate–chit­o­san -poly­ethy­le­neg­ly­col (ACP) micro­cap­sule ­which new­ly devel­oped in our labor­a­to­ry.
Methods. 1000 ACP micro­cap­sules and APA micro­cap­sules ­were implant­ed ­into the per­i­to­neal cav­ity of Wister ­rats, and ­retrieved at 4 ­days and 3 ­weeks ­after implan­ta­tion. The num­ber of ­retrieved micro­cap­sules and per­cent­age of micro­cap­sules ­with per­i­cap­su­lar fibro­sis ­were record­ed. 50, 100 and 200 of ­each ­kind of micro­cap­sule ­were co-cul­tured ­with ­human ser­um, the abil­ity of com­ple­ment acti­va­tion of ­these micro­cap­sules ­were record­ed. Isolated rat ­islets ­were micro­en­cap­su­lat­ed ­with ACP micro­en­cap­su­lates and APA micro­cap­su­lates, the ­amounts of secret­ed insu­lin ­were record­ed ­when ­these encap­su­lat­ed ­islet ­were seri­al­ly cul­tured in Hank’s solu­tion con­tain­ing 3.3­mmol/L and 16.7­mmol/L glu­cose. The unen­cap­su­lat­ed ­islets ­were ­employed as con­trol.
Results. Four ­days ­after implan­ta­tion, the num­ber of ­retrieved micro­cap­sules ­were: ACP micro­cap­sule: 845±40.4; APA micro­cap­sule: 807.6±45.7, ­while the per­cent­age of per­cent­age of micro­cap­sules ­with per­i­cap­su­lar fibro­sis ­were 16.4 and 65.68% (p<0.05). Three ­weeks ­after implan­ta­tion, the num­ber of ­retrieved micro­cap­sules ­were: ACP micro­cap­sule: 715±133; APA micro­cap­sule: 367.5±105.6 (p<0.05), ­while the per­cent­age of re­spective micro­cap­sules ­with per­i­cap­su­lar fibro­sis ­were 27.8% and 83.9% (p<0.05). The resid­u­al com­ple­ment activ­ity of ­human ser­um was ­much high­er in the ACP acti­va­tion ­group. As with unen­cap­su­lat­ed ­islets, the ACP micro­en­cap­su­lat­ed ­islets main­tained the abil­ity of con­sti­tu­tion­al insu­lin secre­tion and stim­u­lat­ed secre­tion ­when chal­lenged with ­high con­cen­tra­tion glu­cose. No sig­nif­i­cant dif­fer­ence was ­observed ­among ­groups.
Conclusions. The ACP micro­cap­sules pos­sess bet­ter bio­com­pat­ibil­ity ­than APA micro­cap­sules.