Veiled cells (VCs) are a population of cells that transport antigens from peripheral tissues to lymph nodes. They are closely related to dendritic cells (DCs) and share similarities in morphology, surface markers, cytochemical staining, and function. Think of them as couriers of the immune system, carrying crucial information (antigens) to alert the lymph nodes to potential threats.
Characteristics and Function of Veiled Cells
- Antigen Transport: VCs are primarily involved in transporting antigens from the periphery to the paracortical areas of lymph nodes. This transport is vital for initiating an adaptive immune response.
- Relationship to Dendritic Cells: Veiled cells are essentially immature dendritic cells. The nomenclature reflects this developmental stage; they are called "veiled" due to their characteristic morphology.
- Location: VCs are found in afferent lymph, the lymph draining from peripheral tissues. They're also found in various tissues including Peyer's patches (lymphoid tissue in the small intestine).
- Morphological Features: While the exact details may vary depending on the source and method of observation, the "veiled" appearance refers to a specific morphology distinguishing them from mature dendritic cells.
Several studies highlight the connection between veiled cells, Langerhans cells (a type of dendritic cell in the skin), and interdigitating cells (DCs in the thymus). They are all part of a family of antigen-presenting cells. The differences may reflect their location and stage of maturation. For example, a monoclonal antibody (NLDC-145) specifically binds to a group of non-lymphoid dendritic cells, including Langerhans cells, veiled cells, and others.
The term "veiled cell" may sometimes be used more broadly, for instance referring to cells surrounding vessels (adventitial cells). The original meaning and predominant use however, pertain to the antigen-presenting cells described above.
