Langhans giant cell

Not to be confused with Langerhans cell.

File:Granulation tissue containg a poorly formed granuloma with a Langhan's giant cell.jpg

Granulation tissue with a poorly formed granuloma to the left of centre. Within this area there is a multinucleate giant cell of the Langhans type. The patient had a healing mycobacterial infection of the skin (M. ulcerans infection).

Langhans giant cells (also known as Pirogov-Langhans cells) are large cells found in granulomatous conditions.

They are formed by the fusion of epithelioid cells (macrophages), and contain nuclei arranged in a horseshoe-shaped pattern in the cell periphery.

Although traditionally their presence was associated with tuberculosis, they are not specific for tuberculosis or even for mycobacterial disease. In fact, they are found in nearly every form of granulomatous disease, regardless of etiology.

Terminology

Langhans giant cells are named after Theodor Langhans (1839–1915), a German pathologist.

They should not be confused with Langerhans cells, which are mononuclear epidermal dendritic cells derived (like Langhans cells) from monocytes and named after Paul Langerhans. (The Islets of Langerhans are also named after Paul Langerhans.)

Causes

Recently, a research paper has shown that when activated CD4+ T cells and monocytes are in close contact, interaction of CD40-CD40L between these two cells and subsequent IFNγ secretion by the T cells causes upregulation and secretion of fusion-related molecule DC-STAMP (dendritic cell-specific transmembrane protein) by the monocytes, which results in LGC formation.

Clinical significance

Langhans cells are often found in transbronchial lung biopsies or lymph node biopsies in patients suffering from sarcoidosis.

External links

• Langhans giant cells at the US National Library of Medicine Medical Subject Headings (MeSH)
• Histology at ohio-state.edu
• Histology at jhu.edu