What is the Difference Between Dendritic Cells and Langerhans Cells

The main difference between dendritic cells and Langerhans cells is that dendritic cells are professional antigen-presenting cells that activate adaptive immune responses, whereas Langerhans cells are immature dendritic cells that reside in the epidermis.    

Dendritic cells and Langerhans cells are two types of cells important in the immune system. Both are important in adaptive immunity.  

Key Areas Covered

1. What are Dendritic Cells
– Definition, Structure, Function
2. What are Langerhans Cells
– Definition, Structure, Function
3. Similarities Between Dendritic Cells and Langerhans Cells
– Outline of Common Features
4. Difference Between Dendritic Cells and Langerhans Cells
– Comparison of Key Differences

Key Terms 

Dendritic Cells, Langerhans Cells

What are Dendritic Cells

Dendritic cells are phagocytes responsible for the immunity of the outer surface of the body, including the skin and gastrointestinal tract. One of the main characteristic features of dendritic cells is the presence of large cytoplasmic veils called dendrites. The activation of the dendritic cells mainly occurs through the inflammatory cytokines secreted by macrophages. Once activated by a particular inflammatory stimulus, dendritic cells cannot take up a second stimulus and become efficient antigen-processing cells. The activated dendritic cells migrate to the T cell areas in the secondary lymphoid organs to present the processed antigens to the naive T cells.

Figure 1: Dendritic Cell

Furthermore, dendritic cells are a type of antigen-presenting cells. They process antigen material and present it on the cell’s surface along with MHC molecules to the T cells of the immune system. Also, dendritic cells occur in tissue like the skin, the inner lining of the nose, lungs, stomach, and the intestines. Immature dendritic cells also appear in the blood. 

What are Langerhans Cells

Langerhans cells are another type of tissue-resident immune cells that serve as antigen-presenting cells. They occur in all epidermis layers and are prominent in the stratum spinosum. Also, they occur in the papillary dermis, around blood vessels, mucosa of the mouth, and vaginal epithelium. Additionally, the primary function of Langerhans cells is to take up microbial antigens, process them, and present antigens to T cells.

Figure 2: Langerhans Cell

Moreover, one of the significant features of Langerhans cells is the presence of Birbeck granules in the cytoplasm. Additionally, Langerhans cells derive from the primitive erythro-myeloid progenitor during embryogenesis. 

Similarities Between Dendritic Cells and Langerhans Cells

• Dendritic cells and Langerhans cells are two types of cells important in the adaptive immune system.
• Both occur in the skin. 
• They are a type of dendritic cells derived from bone marrow.
• They serve as antigen-presenting cells that generate adaptive immune responses. 

Difference Between Dendritic Cells and Langerhans Cells

Definition

Dendritic cells refer to a particular type of immune cell that occurs in tissues, such as the skin, and boosts immune responses by showing antigens on its surface to other immune system cells. In contrast, Langerhans cells refer to a tissue-resident macrophage of the skin once thought to be a resident dendritic cell. 

Structure

Dendritic cells are larger antigen-presenting cells with large cytoplasmic projections that are similar in structure to dendrites of nerve cells. In contrast, Langerhans cells have a dendritic-like phenotype and contain Birbeck granules.

Occurrence

Dendritic cells occur in lung mucosa, the lining of the nose, and the gastrointestinal tract, while Langerhans cells occur suprabasally in most stratified squamous epithelia, such as the epidermis and the epithelium of oral mucosa, including the gingiva. 

Conclusion

In brief, dendritic cells and Langerhans cells are two types of immune cells that induce adaptive immune responses. Both are antigen-presenting cells that occur in the skin. Dendritic cells are large-antigen presenting cells with large cytoplasmic projections. They occur in lung mucosa, the lining of the nose, and the gastrointestinal tract. In comparison, Langerhans cells are similar to dendritic cells, but they contain Birbeck granules. Also, Langerhans cells occur suprabasally in stratified epithelia such as the epidermis and epithelium of the oral mucosa. Therefore, the main difference between dendritic and Langerhans cells is their structure.

References:

1. Fukunaga A, Khaskhely NM, Sreevidya CS, Byrne SN, Ullrich SE. Dermal dendritic cells, and not Langerhans cells, play an essential role in inducing an immune response. J Immunol. 2008 Mar 1;180(5):3057-64. doi: 10.4049/jimmunol.180.5.3057. PMID: 18292528; PMCID: PMC2408377.

Image Courtesy:

1. “Dendritic cell.” By Judith Behnsen, Priyanka Narang, Mike Hasenberg, Frank Gunzer, Ursula Bilitewski, Nina Klippel, Manfred Rohde, Matthias Brock, Axel A. Brakhage, Matthias Gunzer – Own work (CC-BY 2.5) via Commons Wikimedia
2. “Dendritic cell” By Haymanj – Own Work (Public Domain) via Commons Wikimedia