Dendritic Cells

Definition

Dendritic cells are a type of immune cell that play a crucial role in the body's immune response by capturing, processing, and presenting antigens to T cells. These cells serve as a bridge between the innate and adaptive immune systems, facilitating the activation of T cells and promoting the development of adaptive immunity.

5 Must Know Facts For Your Next Test

1. Dendritic cells are often found in tissues that are in contact with the external environment, such as the skin and mucosal surfaces, where they can efficiently capture antigens.
2. They express high levels of major histocompatibility complex (MHC) molecules, which are essential for presenting processed antigens to T cells.
3. Dendritic cells undergo maturation after capturing an antigen, during which they migrate to lymph nodes and become more effective at stimulating T cell responses.
4. These cells not only activate T cells but also help in maintaining tolerance to self-antigens, preventing autoimmune reactions.
5. Different subsets of dendritic cells exist, such as plasmacytoid dendritic cells, which are specialized in producing type I interferons during viral infections.

Review Questions

• How do dendritic cells function as a link between innate and adaptive immunity?
  • Dendritic cells capture antigens from pathogens and process them for presentation to T cells. This ability allows them to act as a crucial bridge between the innate immune response, which provides immediate defense against infections, and the adaptive immune response, which requires time to develop specific immunity. By activating T cells through antigen presentation, dendritic cells help orchestrate a more targeted immune response against the pathogen.
• Discuss the role of dendritic cells in maintaining immune tolerance and preventing autoimmune diseases.
  • Dendritic cells play a vital role in maintaining immune tolerance by presenting self-antigens to T cells in a manner that promotes an unresponsive state rather than activation. This process is crucial for preventing autoimmune diseases where the immune system mistakenly targets the body's own tissues. Through mechanisms such as regulatory T cell induction and cytokine secretion, dendritic cells ensure that T cell activation is appropriately regulated to avoid harmful responses against self-antigens.
• Evaluate how advancements in systems immunology could enhance our understanding of dendritic cell functions and their implications in immunotherapy.
  • Advancements in systems immunology enable researchers to analyze large datasets related to dendritic cell behavior and their interactions with other immune components. By integrating data from various sources such as gene expression profiles and single-cell sequencing, scientists can better understand the diverse roles of dendritic cell subsets in both health and disease. This knowledge could lead to novel immunotherapeutic strategies that harness dendritic cell functions for cancer treatment or vaccine development by enhancing their antigen-presenting capabilities or targeting specific pathways involved in immune modulation.

Related terms

Antigen Presenting Cells (APCs): Cells that process and present antigens to T cells, including dendritic cells, macrophages, and B cells.

T Cell Activation: The process by which T cells are stimulated to proliferate and differentiate in response to specific antigens presented by APCs.

Innate Immunity:

The first line of defense against pathogens, involving nonspecific mechanisms such as physical barriers and immune cells like dendritic cells.