Monitoring Circulating CD207+CD1a+ Cells in Langerhans Cell Histiocytosis and Clinical Implications

J Immunol. 2022 Jul 15;209(2):270-279. doi: 10.4049/jimmunol.2200147. Epub 2022 Jun 29.


Langerhans cell histiocytosis (LCH) is a disorder characterized by an abnormal accumulation of CD207+ and CD1a+ cells in almost any tissue. Currently, there is a lack of prognostic markers to follow up patients and track disease reactivation or treatment response. Putative myeloid precursors CD207+ and CD1a+ cells were previously identified circulating in the blood. Therefore, we aim to develop a sensitive tracing method to monitor circulating CD207+ and CD1a+ cells in a drop of blood sample of patients with LCH. A total of 202 blood samples from patients with LCH and 23 controls were tested using flow cytometry. A standardized cellular score was defined by quantifying CD207+ and CD1a+ expression in monocytes and dendritic cells, based on CD11b, CD14, CD11c, and CD1c subpopulations, resulting in a unique value for each sample. The scoring system was validated by a receiver operating characteristic curve showing a reliable discriminatory capacity (area under the curve of 0.849) with a threshold value of 14, defining the presence of circulating CD207+ and CD1a+ cells. Interestingly, a fraction of patients with no evident clinical manifestation at the time of sampling also showed presence of these cells (29.6%). We also found a differential expression of CD207 and CD1a depending on the organ involvement, and a positive correlation between the cellular score and plasma inflammatory markers such as soluble CD40L, soluble IL-2Ra, and CXCL12. In conclusion, the analysis of circulating CD207 and CD1a cells in a small blood sample will allow setting a cellular score with minimal invasiveness, helping with prognostic accuracy, detecting early reactivation, and follow-up.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, CD / metabolism
  • Antigens, CD1 / metabolism
  • Histiocytosis, Langerhans-Cell* / diagnosis
  • Histiocytosis, Langerhans-Cell* / metabolism
  • Humans
  • Langerhans Cells
  • Lectins, C-Type / metabolism
  • Mannose-Binding Lectins* / metabolism


  • Antigens, CD
  • Antigens, CD1
  • CD1a antigen
  • CD207 protein, human
  • Lectins, C-Type
  • Mannose-Binding Lectins