ALCAM - Activated leukocyte cell adhesion molecule | Elisa - Clia - Antibody - Protein

Background:

Activated leukocyte cell adhesion molecule (ALCAM), also known as CD166, is a cell surface glycoprotein that belongs to the immunoglobulin superfamily. It plays a significant role in cell-cell adhesion and signaling processes, particularly in the immune system and in various developmental processes. ALCAM is widely expressed in various tissues and cell types, including leukocytes, endothelial cells, neurons, and cancer cells. Its functions include: Cell-Cell Adhesion: ALCAM mediates homophilic (like-to-like) and heterophilic (different molecules) interactions between cells. It facilitates the adhesion of leukocytes to endothelial cells, which is essential for immune cell recruitment to sites of inflammation and in the immune response. Neuronal Development: ALCAM is involved in neuronal migration, axon growth, and guidance during brain development. It helps regulate the formation of neural circuits and synaptic connections. Cancer Progression: ALCAM expression has been implicated in cancer progression and metastasis. It can promote tumor cell migration, invasion, and metastasis by enhancing cell adhesion and facilitating interactions between cancer cells and the surrounding microenvironment.Stem Cell Maintenance: ALCAM is involved in the maintenance and regulation of stem cell populations in various tissues. It plays a role in stem cell adhesion, migration, and differentiation.

Protein Structure:

• Molecular Weight: Approximately 105-120 kDa.
• Amino Acid Sequence: Composed of 583 amino acids.
• Domains: The extracellular region contains five immunoglobulin-like domains (VVC2C2C2), while the intracellular region is relatively short.
• Post-translational Modifications: Includes N-glycosylation, which is critical for its stability and function.

Classification and Subtypes:

• Gene Family: Part of the immunoglobulin superfamily (IgSF).
• Isoforms: Alternative splicing of the ALCAM gene results in multiple isoforms, which may have different functional properties.

Function and Biological Significance:

• Cell Adhesion: Mediates homophilic (ALCAM-ALCAM) and heterophilic (ALCAM-CD6) cell-cell adhesion, important for immune cell interactions and tissue organization.
• Immune Response: Involved in the activation and migration of leukocytes, playing a critical role in the immune response.
• Neural Development: Contributes to neuronal growth and synapse formation, impacting nervous system development.
• Cancer Metastasis: ALCAM expression is often altered in various cancers, where it can influence tumor growth, invasion, and metastasis.

Interactions:

• CD6: A known binding partner on T cells and other immune cells, involved in T cell activation and signaling.
• Cytoskeleton: Interacts with cytoskeletal components to maintain cell shape and motility.

Clinical Issues:

• Cancer: ALCAM is overexpressed in several cancers, including melanoma, breast cancer, prostate cancer, and colorectal cancer. Its expression levels correlate with tumor progression and poor prognosis.
• Autoimmune Diseases: Altered ALCAM expression has been linked to autoimmune conditions such as multiple sclerosis and rheumatoid arthritis, where it influences leukocyte migration and activation.
• Therapeutic Target: Due to its role in cancer and immune response, ALCAM is being explored as a potential therapeutic target for antibody-based therapies and small-molecule inhibitors.

Summary:

Activated leukocyte cell adhesion molecule (ALCAM), or CD166, is a versatile adhesion protein crucial for various physiological processes, including immune response, neural development, and cancer metastasis. As a member of the immunoglobulin superfamily, it facilitates cell-cell interactions through its five immunoglobulin-like domains. Clinically, ALCAM's expression levels serve as biomarkers for cancer prognosis and potential therapeutic targets in oncology and autoimmune diseases.