doktorska disertacija
Povzetek
Astrociti so homeostatične celice centralnega živčevja, ki se odzivajo na patološke dražljaje s procesom aktivacije. Vnetni citokin interferon γ (IFNγ) v astrocitih inducira izražanje molekul poglavitnega histokompatibilnostnega kompleksa razreda II (MHCII), ki so potrebne za predstavitev antigenov. Izolirane astrocite tradicionalno gojimo v celični kulturi s serumom, ki poveča bazalno raven aktivacije in spremeni njihovo morfologijo ter znotrajcelično signalizacijo s kalcijevimi ioni. Vpliv obeh prožilcev aktivacije astrocitov na elementarne dogodke ekso-/endocitoze v astrocitih je nepoznan. V delu smo zato raziskali dinamiko in lastnosti elementarnih dogodkov ekso-/endocitoze v podganjih netretiranih serumskih astrocitih, serumskih astrocitih, tretiranih z IFNγ in astrocitih v brezserumski kulturi. Znotrajcelično porazdelitev imunofluorescenčno označenih molekul MHCII smo analizirali s konfokalno mikroskopijo in mikroskopijo s strukturirano osvetlitvijo, lastnosti elementarnih dogodkov ekso-/endocitoze smo raziskali z meritvami membranske kapacitivnosti z metodo vpete napetosti krpice membrane. V astrocitih, tretiranih z IFNγ, so se molekule MHCII lokalizirale pretežno v pozne endo-/lizosome, vendar so dosegle tudi plazmalemo. Z njo so prehodno interagirali večji eksocitotski mešički, medtem ko so bili inhibirani dogodki popolne endocitoze. Ekso-/endocitotska dejavnost brezserumskih astrocitov je bila primerljiva z dejavnostjo serumskih astrocitov v spontanih razmerah, medtem ko je bil zavrt njihov ekso-/endocitotski odziv na draženje z ATP. Aktivacija astrocitov v kulturi z IFNγ ali serumom spremeni dinamiko elementarnih dogodkov ekso-/endocitoze in podaljša zadrževanje molekul MHCII na površini.
Ključne besede
astrociti;eksocitoza;endocitoza;aktivacija astrocitov;predstavitev antigenov;serum;elektrofiziologija;meritve kapacitivnosti;doktorske disertacije;
Podatki
Jezik: |
Slovenski jezik |
Leto izida: |
2020 |
Tipologija: |
2.08 - Doktorska disertacija |
Organizacija: |
UL MF - Medicinska fakulteta |
Založnik: |
[M. Božić] |
UDK: |
576.3:611.8(043.3)=163.6 |
COBISS: |
49776643
|
Št. ogledov: |
518 |
Št. prenosov: |
91 |
Ocena: |
0 (0 glasov) |
Metapodatki: |
|
Ostali podatki
Sekundarni jezik: |
Angleški jezik |
Sekundarni naslov: |
Elementary exocytotic and endocytotic events in activated cultured astrocytes |
Sekundarni povzetek: |
Astrocytes are homeostatic glial cells in the central nervous system that respond to pathologic changes with a process of activation. Interferon γ (IFNγ), an inflammatory cytokine, induces astrocyte expression of major histocompatibility class II (MHCII) molecules required for antigen presentation. Isolated astrocytes are traditionally cultured with serum; however, serum increases astrocyte basal activation and alters their morphology and intracellular calcium signalling. The impact of both triggers of astrocyte activation on exo-/endocytotic activity in astrocytes is not understood. We have thus studied the properties and dynamics of exo-/endocytotic events in non-treated and IFNγ-treated serum as well as serum-free cultured rat astrocytes. The intracellular distribution of immunofluorescently labelled MHCII molecules was analysed with confocal and structural illumination microscopies. Furthermore, elementary exo-/endocytotic activity was studied by patch clamp membrane capacitance measurements. In IFNγ-treated astrocytes, MHCII molecules predominantly localized to late endo-/lysosomes, but also reached the plasmalemma. Additionally, larger exocytotic vesicles reversibly interacted with the plasmalemma, while full endocytotic events were inhibited. Exo-/endocytotic activity of astrocytes in serum-free culture was unaltered at rest, however their exo-/endocytotic activity in response to ATP stimulation was suppressed. Activated cultured astrocytes instigated by treatment with IFNγ or serum culture supplementation display altered dynamics of elementary exo-/endocytotic activity and prolonged surface retention of MHCII. |
Sekundarne ključne besede: |
astrocytes;exocytosis;endocytosis;astrocyte activation;antigen presentation;serum;electrophysiology;capacitance measurements; |
Vrsta dela (COBISS): |
Doktorsko delo/naloga |
Študijski program: |
0 |
Konec prepovedi (OpenAIRE): |
1970-01-01 |
Komentar na gradivo: |
Univ. v Ljubljani, Biotehniška fak. |
Strani: |
XII f., 89 str. |
ID: |
12349038 |