Chemokines

Key Biological Properties: CCL1 is a small glycoprotein with a molecular weight of approximately 15-16 kDa . It is secreted by activated monocytes, macrophages, T lymphocytes, and endothelial cells .

Expression Patterns: CCL1 is expressed by specifically activated T cells upon secondary stimulation .

Tissue Distribution: CCL1 is found in various tissues, including lymphoid tissues, bone marrow, and endothelial cells .

Primary Biological Functions: CCL1 acts as a chemoattractant for monocytes, macrophages, T lymphocytes, especially Th2-differentiated T cells, and a subset of T regulatory cells . It also attracts NK cells and immature B cells but does not attract neutrophils .

Role in Immune Responses: CCL1 plays a crucial role in immune responses by recruiting leukocytes to inflammatory sites . It also inhibits apoptosis in thymic cell lines by the RAS/MAPK pathway .

Pathogen Recognition: CCL1 is involved in the recognition and response to pathogens by mediating the recruitment of immune cells to sites of infection .

Mechanisms with Other Molecules and Cells: CCL1 binds to the chemokine receptor CCR8, inducing Ca2+ influx, chemotaxis, and regulating apoptosis .

Binding Partners: The primary binding partner of CCL1 is the CCR8 receptor .

Downstream Signaling Cascades: Upon binding to CCR8, CCL1 triggers downstream signaling cascades that lead to increased intracellular calcium levels and activation of the RAS/MAPK pathway .

Transcriptional Regulation: The expression of CCL1 is regulated at the transcriptional level by various factors, including the viral transactivator Tax .

Post-Translational Modifications: CCL1 undergoes post-translational modifications, such as C-terminal clipping by carboxypeptidase M (CPM), which enhances its biological activity .

Biomedical Research: CCL1 is used in research to study its role in immune responses, inflammation, and cancer .

Diagnostic Tools: CCL1 levels can be measured as a biomarker for certain diseases, including chronic obstructive pulmonary disease (COPD) and adult T-cell leukemia .

Therapeutic Strategies: Targeting CCL1 and its receptor CCR8 is being explored as a potential therapeutic strategy for inflammatory diseases and cancer .

Development: CCL1 plays a role in the development of the immune system by recruiting immune cells to sites of inflammation and infection .

Aging: The expression and activity of CCL1 may change with aging, potentially affecting immune responses and inflammation .

Disease: Dysregulation of CCL1 is associated with various diseases, including chronic inflammatory diseases, cancer, and neuroinflammatory disorders .