Fibroblastspecific

Fibroblast-specific refers to characteristics, markers, or genetic elements that are used to identify or manipulate fibroblasts, a diverse group of mesenchymal cells responsible for producing and remodeling extracellular matrix in connective tissue. The term is often encountered in the context of markers, promoters, or therapeutic targets that are assumed to be enriched in fibroblasts, though true exclusivity is uncommon and context-dependent.

Markers and promoters commonly described as fibroblast-specific are not universally exclusive. Examples include FSP1 (S100A4), which has historically been used as a fibroblast marker but can be expressed by other cell types during inflammation; PDGFRα and PDGFRβ, used in lineage tracing and gene targeting; and Col1a1 or Col1a2 promoters, employed to drive gene expression in fibroblasts but also active in other mesenchymal populations. The fibroblast activation protein (FAP) is associated with activated fibroblasts such as cancer-associated fibroblasts and wound-healing fibroblasts, making it a practical target in certain settings. CD90 (Thy1) is another commonly noted fibroblast-associated marker but is not exclusive to fibroblasts.

Fibroblasts are a heterogeneous group, and markers can vary by tissue, developmental stage, and physiological conditions. Distinguishing fibroblasts from related cell types, such as myofibroblasts, fibrocytes, and pericytes, often requires multiple markers and contextual information, including gene expression profiles revealed by single-cell analysis.

Applications of the concept include lineage tracing, targeted gene delivery in research models, and potential therapeutic strategies for fibrosis or cancer. Limitations arise from marker overlap, tissue-specific variation, and dynamic expression during disease or repair processes. See also fibroblast, myofibroblast, cancer-associated fibroblast, FAP, FSP1/S100A4.