IFN-γ-induced increase in the mobility of MHC class II compartments in astrocytes depends on intermediate filaments

التفاصيل البيبلوغرافية
العنوان: IFN-γ-induced increase in the mobility of MHC class II compartments in astrocytes depends on intermediate filaments
المؤلفون: Vardjan, Nina, Gabrijel, Mateja, Potokar, Maja, Švajger, Urban, Kreft, Marko, Jeras, Matjaž, de Pablo, Yolanda, Faiz, Maryam, Pekny, Milos, Zorec, Robert
بيانات النشر: BioMed Central Ltd.
سنة النشر: 2012
المجموعة: BioMed Central
مصطلحات موضوعية: Astrocytes, Vesicle mobility, Late endosomes/lysosomes, Major histocompatibility class II compartments, Interferon-γ, Dextran labeling, Immune response
الوصف: Background In immune-mediated diseases of the central nervous system, astrocytes exposed to interferon-γ (IFN-γ) can express major histocompatibility complex (MHC) class II molecules and antigens on their surface. MHC class II molecules are thought to be delivered to the cell surface by membrane-bound vesicles. However, the characteristics and dynamics of this vesicular traffic are unclear, particularly in reactive astrocytes, which overexpress intermediate filament (IF) proteins that may affect trafficking. The aim of this study was to determine the mobility of MHC class II vesicles in wild-type (WT) astrocytes and in astrocytes devoid of IFs. Methods The identity of MHC class II compartments in WT and IF-deficient astrocytes 48 h after IFN-γ activation was determined immunocytochemically by using confocal microscopy. Time-lapse confocal imaging and Alexa Fluor 546 -dextran labeling of late endosomes/lysosomes in IFN-γ treated cells was used to characterize the motion of MHC class II vesicles. The mobility of vesicles was analyzed using ParticleTR software. Results Confocal imaging of primary cultures of WT and IF-deficient astrocytes revealed IFN-γ induced MHC class II expression in late endosomes/lysosomes, which were specifically labeled with Alexa Fluor 546 -conjugated dextran. Live imaging revealed faster movement of dextran-positive vesicles in IFN-γ-treated than in untreated astrocytes. Vesicle mobility was lower in IFN-γ-treated IF-deficient astrocytes than in WT astrocytes. Thus, the IFN-γ-induced increase in the mobility of MHC class II compartments is IF-dependent. Conclusions Since reactivity of astrocytes is a hallmark of many CNS pathologies, it is likely that the up-regulation of IFs under such conditions allows a faster and therefore a more efficient delivery of MHC class II molecules to the cell surface. In vivo, such regulatory mechanisms may enable antigen-presenting reactive astrocytes to respond rapidly and in a controlled manner to CNS inflammation.
نوع الوثيقة: report
اللغة: English
Relation: http://www.jneuroinflammation.com/content/9/1/144
الاتاحة: http://www.jneuroinflammation.com/content/9/1/144
Rights: Copyright 2012 Vardjan et al.; licensee BioMed Central Ltd.
رقم الانضمام: edsbas.C5F16D6F
قاعدة البيانات: BASE