Grants Awarded

Osteopontin Expression and Function in Langerhans Cell Histiocytosis

Principal Investigator and Co-Investigators
Carl E. Allen MD, PhD (PI); Tricia L. Peters MD, MS; Kenneth L. McClain MD, PhD
Baylor College of Medicine – Houston, Texas USA

Date of Award
November 2009

Amount of Award

Layperson Summary
Langerhans Cell Histiocytosis (LCH) is a rare but potentially fatal disease in which the cause is unknown. LCH lesions consist of a variety of cell types, including Langerhans cells, T-lymphocytes and eosinophils. We have recently discovered that the cytokine osteopontin (OPN) is overexpressed in LCH tissue, and that patients with active multisystem disease have higher plasma OPN levels. This suggests that OPN may play a functional role in the development of this disease.

Specific Aims and Hypothesis:
Based on our preliminary data, we propose to further explore the expression of OPN and its receptors in LCH and determine if OPN regulates T-lymphocyte activation and function in LCH.

  • To compare OPN expression in LCH lesions and plasma from LCH patients and to determine which forms of OPN protein are expressed.
  • To determine which OPN receptors are expressed in LCH lesions.
  • To determine if OPN affects T-lymphocyte proliferation and migration, and investigate which OPN receptors are involved in the T-lymphocyte response in LCH.

Potential Impact:
The ultimate goal of this study is to identify new diagnostic and therapeutic targets for treatment and cure of LCH. These experiments may also provide insight into dendritic cell biology and tumor immunology.