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Dendritic Cells: Dendritic Cell Origin, Function and Related Conditions

3D rendering of a dendritic cell, showing the finger like projections on its surface.
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Read time: 6 minutes

The immune system is incredibly complex and interconnected. The many facets of the system, with a variety of specialized tasks, function in cooperation to defend our bodies from external threats.



In this article, we consider what dendritic cells (DCs) are, how they are generated, their function in the body and some medical conditions related to them.


What are dendritic cells?

DCs are named for their distinctive branching projections called dendrites. They are classed as professional antigen-presenting cells (APCs), meaning they function by capturing, processing and presenting antigens to other immune cells, primarily T cells. Ralph M. Steinman and Zanvil A. Cohn were the first to describe DCs in 1973,1 work that earned Steinman the 2011 Nobel prize for medicine and physiology.


As with many immune cells, DCs start life in the bone marrow as hematopoietic stem cells that are able to differentiate into numerous cell types. To form DCs, the myeloid progenitor cell derived from the stem cell first differentiates into a common DC precursor. Subsequent differentiation then produces plasmacytoid DCs (pDCs), as well as a circulating DC (cDC) precursor (pre-cDC) (Figure 1). In addition to these two types of DC there are also two subsets derived from monocytes, the monocyte-derived DCs (moDCs) and Langerhans cells (LCs).2 Subsequently, and especially in the case of cDC’s, different types of DCs acquire different characteristics in different environments.3 The life span of DCs varies, significant differences in which have been observed between the subsets.4 DCs have a unique morphology that contributes to their function as professional APCs. The morphology and size of dendritic cells can vary depending on their tissue location and activation state.

Flow diagram showing the differentiation pathway for the development of dendritic cells. Related and intermediate cell types shown and illustrated.


Figure 1: Diagram showing the differentiation pathway for the development of dendritic cells. Credit: Technology Networks.


Dendritic cell function

DCs play a critical role in the immune system, serving as professional APCs that bridge the innate and adaptive immune responses. Their functions are diverse and crucial for initiating, coordinating and regulating immune responses. DCs use various receptors to recognize pathogens, damaged or cancerous cells or foreign substances. They capture antigens from their surroundings and process them by breaking them down into smaller fragments. They then present processed antigenic peptides on their cell surface using major histocompatibility complexes (MHC). This presentation is essential for the activation of CD8+ and CD4+ T lymphocytes (T cells) and the initiation of adaptive immune responses.

The activated T cells can then proliferate and differentiate. They can become either cytotoxic T cells that release potent cytotoxic chemicals such as perforins and granzyme to kill the invading agent or cancerous cell, or T helper cells that interact with B cells, leading to the production of antibodies, which are important in the elimination of pathogens.5 T helper cells are also critical for the production of memory cells that enable a more rapid response to a pathogen if it is encountered again (Figure 2).6 There is also crosstalk between DCs and natural killer cells (NK cells) resulting in maturation, activation and cytokine production by both cell types.7 DCs are critically important in maintaining tolerance in both in the central and peripheral lymphatic systems, the process by which the body is able to recognize and accept the body’s tissues as “self”.8 Additionally, DCs can produce cytokines and respond to cytokine-mediated activation, thus helping to regulate the balance between inflammation, immunity and tolerance.9 Finally, DCs have been shown to be able to interact directly with B cells, present antigens directly to them and initiate antibody production.10Representation of dendritic cell interactions with B cells and T cells.


Figure 2: Dendritic cell interactions with B cells and T cells. Credit: Technology Networks.


Dendritic cell-related conditions

Dysregulation of DC function can be associated with various diseases. Some diseases linked to abnormalities in dendritic cell function include:

  1. Autoimmune diseases: Abnormal dendritic cell activation and presentation of self-antigens may contribute to autoimmune diseases like rheumatoid arthritis, lupus erythematosus, autoimmune myocarditis, psoriasis, multiple sclerosis and type 1 diabetes.11 The exact causes of many DC-associated autoimmune conditions are complex but include genetic, epigenetic, environmental and hormonal factors, as well as some treatments and infection.

  2. Langerhans cell histiocytosis: This rare disorder is characterized by the proliferation of Langerhans cells leading to the formation of granulomas. It can affect various organs, including the skin, bones and other tissues. The disease spectrum can range from a localized, self-limiting form to a more severe, disseminated form.12

  3. Dendritic cell deficiency (DCD): This is a rare primary immunodeficiency disorder characterized by a deficiency or dysfunction of DCs. Patients with DCD may experience recurrent infections due to impaired immune responses. DCD can result from genetic mutations in both GATA-binding factor 2 (GATA2) or interferon regulatory factor 8 (IRF8).13

  4. Inflammatory bowel diseases (IBD): IBD are a group of inflammatory conditions affecting the intestinal tract, the most common being Crohn’s disease and ulcerative colitis. They have different characteristics, with ulcerative colitis presenting as continuous inflammation of the rectum extending into the colon, whereas Crohn’s disease is more discontinuous and can present anywhere in the intestinal tract. Many IBD susceptibility mutations have been identified in dendritic cells that either prevent the elimination of pathogens or cause an excessive immune response.14


DCs are the key link between the innate and adaptive immune responses. Their role as professional APCs and ability to secrete numerous cytokines helps to regulate immune function in a vast array of different ways, facilitating the elimination of pathogens and cancer cells while enforcing tolerance to self and harmless stimuli.

1.      Steinman RM, Cohn ZA. Identification of a novel cell type in peripheral lymphoid organs of mice. I. Morphology, quantitation, tissue distribution. J Exp Med. 1973 May 1;137(5):1142-62. doi:10.1084/jem.137.5.1142

2.      Seillet C, Belz GT. Terminal differentiation of dendritic cells. Adv Immunol. 2013;120:185-210. doi:10.1016/B978-0-12-417028-5

3.      Sichien D, Lambrecht BN, Guilliams M, Scott CL. Development of conventional dendritic cells: from common bone marrow progenitors to multiple subsets in peripheral tissues. Mucosal Immunol. (2017) 10:831–44. doi:10.1038/mi.2017.8

4.      Chen M, Huang L, Shabier Z, Wang J. Regulation of the lifespan in dendritic cell subsets. Mol Immunol. 2007 Apr;44(10):2558-65. doi:10.1016/j.molimm.2006.12.020

5.      Mellman I. Dendritic cells: master regulators of the immune response. Cancer Immunol Res. 2013 Sep;1(3):145-9. doi:10.1158/2326-6066.CIR-13-0102

6.      Ratajczak W, Niedźwiedzka-Rystwej P, Tokarz-Deptuła B, Deptuła W. Immunological memory cells. Cent Eur J Immunol. 2018;43(2):194-203. doi:10.5114/ceji.2018.77390

7.      Thomas R, Yang X. NK-DC Crosstalk in immunity to microbial infection. J Immunol Res. 2016;2016:6374379. doi:10.1155/2016/6374379

8.      Steinman RM, Hawiger D, Nussenzweig MC. Tolerogenic dendritic cells. Annu Rev Immunol. 2003;21:685-711. doi:10.1146/annurev.immunol.21.120601.141040

9.      Blanco P, Palucka AK, Pascual V, Banchereau J. Dendritic cells and cytokines in human inflammatory and autoimmune diseases. Cytokine Growth Factor Rev. 2008 Feb;19(1):41-52. doi:10.1016/j.cytogfr.2007.10.004

10.   Heath WR, Kato Y, Steiner TM, Caminschi I. Antigen presentation by dendritic cells for B cell activation. Curr Opin Immunol. 2019 Jun;58:44-52. doi:10.1016/j.coi.2019.04.003

11.   Ganguly D, Haak S, Sisirak V, Reizis B. The role of dendritic cells in autoimmunity. Nat Rev Immunol. 2013 Aug;13(8):566-77. doi:10.1038/nri3477

12.   Tillotson CV, Anjum F, Patel BC. Langerhans cell histiocytosis. [Updated 2023 Jul 17]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK430885/

13.   Collin, M., Bigley, V., Haniffa, M. et al. Human dendritic cell deficiency: The missing ID?. Nat Rev Immunol 11, 575–583 (2011). doi:10.1038/nri3046

14.   Bates J, Diehl L. Dendritic cells in IBD pathogenesis: an area of therapeutic opportunity? J Pathol. 2014 Jan;232(2):112-20. doi:10.1002/path.4277