Naslov
Conformed and nonconformed MHC class I molecules are internalized by different mechanisms, but rich the same endocytotic compartments

Autori
Mahmutefendić, Hana ; Blagojević, Gordana ; Kučić, Natalia ; Lučin, Pero

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Annual meeting, Croatian Immunological Society/ Hrvatsko imunološko društvo / Hrvatsko imunološko društvo - Rijeka : Hrvatsko imunološko društvo, 2005

Skup
Annual meeting, Croatian Immunological Society/ Hrvatsko imunološko društvo

Mjesto i datum
Božava, Hrvatska, 29.09.2005. - 02.10.2005

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
MHC class I molecules; endocytosis; vesicular trafficking

Sažetak
Problem: The aim of our study was to compare the internalization mechanisms and endocytic trafficking of conformed and non-conformed Dd and Ld molecules on non-polarized cell lines (P815 mastocytoma cell line and Balb 3T3 fibroblast cell line). Material and methods: Endocytosis of Dd and Ld molecules was followed in a model of cycloheximide-induced spontaneous internalization in combination with inhibitors of endocytosis. Transformation of class I molecules conformation was achieved by short acidification of cell culture medium. The cell surface expression of Dd and Ld molecules was determined by flow cytometry, and intracellular colocalization with markers of the endocytic pathway by confocal microscopy. Cell surface biotinylation, followed by immunoprecipitation and SDS-PAGE, was used to determine the kinetics of degradation. Finally, localization of class I molecules in detergent insoluble membrane domains was determined by short ice-cold Triton X treatment and confocal microscopy. Results: Non-conformed Dd and Ld molecules were localized in the lipid rafts and were internalized by cholesterol dependent mechanism that is not caveolar. In contrast, conformed class I molecules were internalized by the bulk pathway and did not localize in the lipid rafts. However, both conformed and non-conformed molecules were found in Rab5B positive compartments 10 minutes after internalization, but with different intensity. At the end, both types of class I molecules are degraded in lysosomes. Conclusion: Conformed and non-conformed Dd and Ld molecules are internalized by different mechanisms, but their endocytic pathways are subsequently intersected in early endosomes and lysosomes.

Izvorni jezik
Engleski

POVEZANOST RADA