Aberrant tissue positioning of metallophilic macrophages in the thymus of XCL1-deficient mice

Anat Rec (Hoboken). 2014 Aug;297(8):1472-7. doi: 10.1002/ar.22935. Epub 2014 Apr 29.

Abstract

Metallophilic macrophages hold a strategic position within the thymic tissue and play a considerable function in thymic physiology. The development and positioning of these cells within thymic tissue are regulated by complex molecular mechanisms involving different cytokine/chemokine axes. Herein, we studied the role of XCL1 signaling in these processes. We show that in the XCL1-deficient thymus numerous metallophilic macrophages are aberrantly positioned in the thymic cortex, instead of their normal location in the cortico-medullary zone. Still, these cells retain their normal appearance: very large size with prominent, ramifying cytoplasmic prolongations. This shows that XCL1 signaling is not involved in morphological development, but rather in correct positioning of metallophilic macrophages within the thymic tissue. In contrast to thymic metallophilic macrophages, the positioning of splenic marginal metallophilic macrophages is not affected by XCL1-deficiency.

Keywords: chemokine receptors; chemokines; dendritic cells; metallophilic macrophages; mouse; thymus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AIRE Protein
  • Animals
  • Chemokines, C / physiology*
  • Female
  • Immunoenzyme Techniques
  • Macrophages / cytology*
  • Macrophages / metabolism
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Silver / chemistry*
  • Spleen / cytology*
  • Spleen / metabolism
  • Thymus Gland / cytology*
  • Thymus Gland / metabolism
  • Transcription Factors / physiology*

Substances

  • Chemokines, C
  • Transcription Factors
  • Xcl1 protein, mouse
  • Silver