TGF-beta is required to maintain the pool of immature Langerhans cells in the epidermis

J Immunol. 2010 Sep 15;185(6):3248-55. doi: 10.4049/jimmunol.1000981. Epub 2010 Aug 16.

Abstract

The pivotal role of TGF-beta in Langerhans cell (LC) development has been previously established in TGF-beta-deficient mice, which lack epidermal LCs. As to whether TGF-beta also governs LC homeostasis and function remains elusive. To assess the role of TGF-beta-mediated control of cutaneous dendritic cells (DCs) in vivo, we generated mice with a conditional knockout of the TGF-beta receptor 1 (TbetaR1) under a DC-specific promoter (DC-TbetaR1(del) mice). While initial LC seeding occurred in DC-TbetaR1(del) mice, the cells disappeared from the epidermis during the first week of life. TbetaR1-deficient LCs demonstrated spontaneous maturation and gained migratory potential based on increased surface expression of MHC class II, costimulatory molecules, and CCR7 and downregulation of E-cadherin. In parallel to their early loss from the epidermis, migrating LCs were reduced in the dermis and skin-draining lymph nodes of adult DC-TbetaR1(del) mice, whereas the number of Langerin(+) dermal DCs was similar to wild-type. In the absence of LCs, low-dose contact hypersensitivity in DC-TbetaR1(del) mice was significantly diminished. In contrast, ear swelling was restored to wild-type levels when a higher hapten dose was applied to efficiently target TbetaR1-deficient dermal DCs. In conclusion, TGF-beta inhibits in vivo LC maturation and migratory phenotype, identifying TGF-beta as a critical factor controlling LC homeostasis in the steady state.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Differentiation / genetics
  • Cell Differentiation / immunology*
  • Cell Movement / genetics
  • Cell Movement / immunology
  • Cells, Cultured
  • Dermatitis, Contact / immunology
  • Dermatitis, Contact / metabolism
  • Dermatitis, Contact / pathology
  • Epidermal Cells*
  • Epidermis / immunology*
  • Epidermis / pathology
  • Homeostasis / genetics
  • Homeostasis / immunology
  • Langerhans Cells / cytology*
  • Langerhans Cells / immunology*
  • Langerhans Cells / pathology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mice, Transgenic
  • Protein Serine-Threonine Kinases / deficiency
  • Protein Serine-Threonine Kinases / genetics
  • Receptor, Transforming Growth Factor-beta Type I
  • Receptors, Transforming Growth Factor beta / deficiency
  • Receptors, Transforming Growth Factor beta / genetics
  • Transforming Growth Factor beta1 / physiology*

Substances

  • Receptors, Transforming Growth Factor beta
  • Transforming Growth Factor beta1
  • Protein Serine-Threonine Kinases
  • Receptor, Transforming Growth Factor-beta Type I