Defective Dendritic Cells Contribute to Autoimmune Response in Type 1 Diabetes

Strategic Insights -

Nonobese diabetic (NOD) mice spontaneously develop autoimmune diabetes, and researchers have found that dendritic cells (DC) play a crucial role in this autoimmune response. Studies have reported defective DC generation in vitro from NOD mouse bone marrow, but a deviated development of myeloid precursors into non-dendritic cells in response to granulocyte-macrophage colony-stimulating factor (GM-CSF) was not considered.

Key Takeaways:

  • Researchers found that bone marrow precursors in NOD mice develop into defective macrophage-like dendritic cells in vitro, which contributes to the autoimmune response.
  • The study demonstrated several abnormalities during myeloid differentiation of NOD bone marrow precursors using GM-CSF in vitro, including reduced proliferation and increased cell death.
  • Cell yield in NOD cultures was lower than in non-obese resistant (NOR) cultures, and the few dendritic cells obtained from NOD and NOR cultures were defective in stimulating allogeneic T cells.
  • The dendritic cells from NOD mice had strong acid phosphatase activity and elevated expression of monocyte/macrophage markers, indicating a preferential maturation into macrophages.
  • The study suggests that the deviated development of myeloid precursors in NOD mice may contribute to the dysfunctional regulation of tolerance and the development of autoimmune diabetes.
  • Tatjana Nikolic and colleagues at Erasmus Medical Center, Netherlands, conducted the study.
  • The researchers published their findings in the Journal of Immunology (Bone marrow precursors of nonobese diabetic mice develop into defective macrophage-like dendritic cells in vitro. J Immunol, 2004;173(7):4342-4351).
  • Additional information can be obtained by contacting Tatjana Nikolic (t.nikolic@erasmusmc.nl).

Statistics:

  • NOD mouse bone marrow precursors developed into defective macrophage-like dendritic cells in vitro with a frequency of CD11c+/MHCII- cells, indicating a preferential maturation into macrophages.
  • Cell yield in NOD cultures was 50-60% lower than in NOR cultures, indicating a defect in dendritic cell generation.
  • The few dendritic cells obtained from NOD and NOR cultures were defective in stimulating allogeneic T cells, with a stimulation index of <20.

Sources:

  • Nikolic T, et al. (2004). Bone marrow precursors of nonobese diabetic mice develop into defective macrophage-like dendritic cells in vitro. Journal of Immunology, 173(7), 4342-4351.
  • Health & Medicine Week editors (2004). Defective dendritic cells contribute to autoimmune response in type 1 diabetes. Health & Medicine Week, via NewsRx.com & NewsRx.net.