Please use this identifier to cite or link to this item:
https://www.arca.fiocruz.br/handle/icict/13776
Type
ArticleCopyright
Open access
Collections
- IOC - Artigos de Periódicos [12341]
Metadata
Show full item record
LAMININ-MEDIATED INTERACTIONS IN THYMOCYTE MIGRATION AND DEVELOPMENT
T-cell development
Thymic epithelial cells
Extracellular matrix
Laminin isoforms
Integrins
Chemokines
Author
Affilliation
Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.
Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.
Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.
Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.
Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.
Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.
Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.
Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.
Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.
Abstract
Intrathymic T-cell differentiation is a key process for the development and maintenance of
cell-mediated immunity, and occurs concomitantly to highly regulated migratory events.
We have proposed a multivectorial model for describing intrathymic thymocyte migration.
One of the individual vectors comprises interactions mediated by laminins (LMs),
a heterotrimeric protein family of the extracellular matrix. Several LMs are expressed in
the thymus, being produced by microenvironmental cells, particularly thymic epithelial
cells (TECs). Also, thymocytes and epithelial cells express integrin-type LM receptors.
Functionally, it has been reported that the dy/dy mutant mouse (lacking the LM isoform
211) exhibits defective thymocyte differentiation. Several data show haptotactic effects of
LMs upon thymocytes, as well as their adhesion on TECs; both effects being prevented
by anti-LM or anti-LM receptor antibodies. Interestingly, LM synergizes with chemokines
to enhance thymocyte migration, whereas classe-3 semaphorins and B ephrins, which
exhibit chemorepulsive effects in the thymus, downregulate LM-mediated migratory
responses of thymocytes. More recently, we showed that knocking down the ITGA6
gene (which encodes the α6 integrin chain of LM receptors) in human TECs modulates a
large number of cell migration-related genes and results in changes of adhesion pattern
of thymocytes onto the thymic epithelium. Overall, LM-mediated interactions can be
placed at the cross-road of the multivectorial process of thymocyte migration, with a
direct influence per se, as well as by modulating other molecular interactions associated
with the intrathymic-trafficking events.
Keywords
ThymusT-cell development
Thymic epithelial cells
Extracellular matrix
Laminin isoforms
Integrins
Chemokines
Share