Chronic exposure to a TLR ligand injures hematopoietic stem cells

Brandt L. Esplin, Tomoyuki Shimazu, Robert S. Welner, Karla P. Garrett, Lei Nie, Qingzhao Zhang, Mary Beth Humphrey, Qi Yang, Lisa A. Borghesi, Paul W. Kincade

Research output: Contribution to journalArticlepeer-review

205 Citations (Scopus)


Hematopoietic stem cells (HSC) can be harmed by disease, chemotherapy, radiation, and normal aging.We show in this study that damage also occurs in mice repeatedly treated with very low doses of LPS. Overall health of the animals was good, and there were relatively minor changes in marrow hematopoietic progenitors. However, HSC were unable to maintain quiescence, and transplantation revealed them to be myeloid skewed. Moreover, HSC from treated mice were not sustained in serial transplants and produced lymphoid progenitors with low levels of the E47 transcription factor. This phenomenon was previously seen in normal aging. Screening identified mAbs that resolve HSC subsets, and relative proportions of these HSC changed with age and/or chronic LPS treatment. For example, minor CD150HiCD48- populations lacking CD86 or CD18 expanded. Simultaneous loss of CD150Lo/-CD48- HSC and gain of the normally rare subsets, in parallel with diminished transplantation potential, would be consistent with age- or TLR-related injury. In contrast, HSC in old mice differed from those in LPS-treated animals with respect to VCAM-1 or CD41 expression and lacked proliferation abnormalities. HSC can be exposed to endogenous and pathogen-derived TLR ligands during persistent low-grade infections. This stimulation might contribute in part to HSC senescence and ultimately compromise immunity.

Original languageEnglish
Pages (from-to)5367-5375
Number of pages9
JournalJournal of Immunology
Issue number9
Publication statusPublished - 2011 May 1
Externally publishedYes

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology


Dive into the research topics of 'Chronic exposure to a TLR ligand injures hematopoietic stem cells'. Together they form a unique fingerprint.

Cite this