Related Experiment Video

Updated: Dec 23, 2025

Studying Organelle Dynamics in B Cells During Immune Synapse Formation
15:39

Studying Organelle Dynamics in B Cells During Immune Synapse Formation

Published on: June 1, 2019

9.5K

The Essential Role of anxA2 in Langerhans Cell Birbeck Granules Formation

Shantae M Thornton1, Varsha D Samararatne1, Joseph G Skeate1

  • 1Department of Molecular Microbiology and Immunology, University of Southern California, Los Angeles, CA 90033, USA.

Cells
|April 25, 2020
PubMed

Insights

Annexin A2 (anxA2) is crucial for forming Birbeck granules (BG) in Langerhans cells (LC). Downregulating anxA2 disrupts BG formation and langerin localization, impacting LC immune function.

Area of Science:

  • Immunology
  • Cell Biology
  • Microscopy

Background:

  • Langerhans cells (LC) are key antigen-presenting cells in mucosal epithelia, initiating immune responses.
  • LC uniquely contain Birbeck granules (BG), organelles composed of langerin, implicated in viral antigen processing and antiviral immunity.

Purpose of the Study:

  • To investigate proteins involved in Birbeck granule (BG) formation.
  • To characterize the structure and function of BG using transmission electron microscopy (TEM).

Main Methods:

  • Investigated the role of annexin A2 (anxA2) in BG formation.
  • Utilized transmission electron microscopy (TEM) for structural analysis.
  • Assessed changes in langerin expression and localization upon anxA2 downregulation.

Main Results:

  • Annexin A2 (anxA2) plays a critical role in the proper formation of Birbeck granules (BG).
  • Downregulation of anxA2 led to decreased langerin expression and near ablation of cytoplasmic BG.
  • Absence of anxA2 resulted in malformed BG-like structures and loss of langerin localization to BG.

Conclusions:

  • Annexin A2 (anxA2) is essential for the structural integrity and formation of Birbeck granules (BG).
  • These findings provide new insights into the molecular mechanisms underlying BG biogenesis and LC function.

Keywords:
A2tBirbeck granulesLangerhans cellanxA2

More Related Videos

Author Spotlight: Exploring Plasma Membrane Repair Mechanisms with Innovative Thermoplasmonic Puncturing06:32

Author Spotlight: Exploring Plasma Membrane Repair Mechanisms with Innovative Thermoplasmonic Puncturing

Published on: January 19, 2024

1.6K
Isolation of Group 2 Innate Lymphoid Cells from Mouse Nasal Mucosa to Detect the Expression of CD22608:30

Isolation of Group 2 Innate Lymphoid Cells from Mouse Nasal Mucosa to Detect the Expression of CD226

Published on: May 10, 2022

2.3K

Related Concept Videos

Overview of Secretory Vesicles01:33

Overview of Secretory Vesicles

Secretory vesicles, also known as dense core vesicles (DCVs), are membrane-bound vesicles that transport secretory proteins, such as hormones or neurotransmitters. Regulated secretory vesicles transport proteins from the trans-Golgi network to the exterior of the cell. Proteins present in regulated secretory vesicles are required to be rapidly exocytosed in large amounts upon a specific stimulus.
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
9.2K
Intralumenal Vesicles and Multivesicular Bodies01:38

Intralumenal Vesicles and Multivesicular Bodies

Intraluminal vesicles (ILVs) are small vesicles 50-80 nm in diameter formed during the maturation of early endosomes. A specialized endosome containing numerous ILVs is called a multivesicular body (MVB). ILVs contain internalized molecules such as antigens, nucleic acids, proteins, and metabolites. Some of these molecules are released from the MVBs inside exosomes and are transported to other cells. Other MVBs contain molecules that are retained in the ILVs and are later degraded within the...
4.5K
Anchoring Junctions01:03

Anchoring Junctions

Anchoring junctions are multiprotein complexes that help cells connect to other cells and the extracellular matrix. Anchoring junctions are present on the lateral and basal surfaces of cells, providing strong and flexible connections. Focal adhesions are often formed due to cell interactions with the ECM substrata, which initiate signal transduction via kinase cascades and other mechanisms. Together, they provide stability and tissue integrity. There are three types of anchoring junctions:...
4.6K
B Cell Activation and Differentiation01:24

B Cell Activation and Differentiation

The adaptive immune response, a sophisticated defense mechanism, relies on the activation and differentiation of B lymphocytes, or B cells. These processes enable our bodies to mount a tailored response against specific pathogens such as bacteria, free virus particles, toxins, and parasites.
When naive B cells encounter a specific antigen that can bind to the B cell receptor (BCR) on their surface, they undergo sensitization to respond to the antigen's presence. Sensitization begins with...
15.6K
Adherens Junctions01:24

Adherens Junctions

Strong contact points between adjacent cells anchor them to each other, forming tissues. Such anchoring junctions are of two types –  adherens junctions and desmosomes. Adherens junctions are abundant in tissues such as  epithelium and endothelium, forming a continuous zone of adhesion called the adhesion belt. In other tissues, such as  heart muscle, they appear as clusters, linking the cells to produce coordinated heart muscle contraction.
Adherens Junctions are Dynamic
6.0K
Antigen Processing Pathways01:31

Antigen Processing Pathways

MHC molecules are key players in the immune response, enabling T cells to recognize and respond to specific antigens. They are present on the surface of all nucleated cells in the body and are instrumental in presenting antigens to T cells and activating them. T cells recognize the MHC-antigen complex and initiate an immune response. MHC class I and MHC class II are two main types of MHC molecules, each associated with a distinct antigen processing pathway.
MHC Class I: Presenting Endogenous...
1.9K