Protein thiol residues on immune cell surface molecules and enzymes

Protein thiol residues on immune cell surface molecules and enzymes serve as critical regulatory switches for cellular signaling and redox homeostasis. These sulfhydryl groups are found on a variety of proteins, including cell surface receptors, transporters, and intracellular enzymes such as thioredoxin reductase and glyceraldehyde-3-phosphate dehydrogenase (PubMed, PMID: 23583553). In the context of the immune system, the redox state of these thiols—specifically exofacial thiols—is vital for T-cell activation, cytokine production, and the modulation of inflammatory responses (PubMed, PMID: 15155614). Pharmacological agents like auranofin and dimethyl fumarate target these residues through covalent modification or coordination, often leading to the inhibition of enzymatic activity or the alteration of protein-protein interactions (PubChem CID 24199; PubMed, PMID: 26035153). While targeting these residues offers therapeutic potential in treating autoimmune diseases, inflammation, and certain cancers, the ubiquity of thiol groups across the proteome presents significant challenges regarding drug specificity and off-target toxicity. Consequently, monitoring thiol-disulfide exchange and total protein thiol levels is often necessary to assess the efficacy and safety of such interventions.

Other names

Exofacial protein thiolsCell surface sulfhydryl groupsMembrane protein thiolsRedox-sensitive protein thiolsProtein sulfhydryls

Covalent modification or coordination of electrophilic or metallic drug moieties with sulfhydryl groups on proteins, leading to functional inhibition or conformational changes.