ORM - Alpha-1-Acid Glycoprotein (Orosomucoid) | Elisa - Clia - Antibody - Protein

Background:

Alpha-1-Acid Glycoprotein (ORM1), also known as orosomucoid, is an acute-phase plasma protein predominantly synthesized in the liver. ORM1 is a part of the acute-phase response, where its levels in the blood increase in response to inflammation, infection, or injury.It is a 43-44 kDa glycoprotein well known as a one of the major acute phase proteins in humans, rats and many other spices The carbohydrate content represents 45% of the molecular weight attached in the form of five to six highly sialylated complex-type-N-linked glycans.ORM1 has since been studied extensively for its role in immune regulation, drug binding, and inflammation.

Protein Structure:

• Length and Composition: ORM1 consists of 183 amino acids.
• Domains: It contains a highly glycosylated region, with multiple glycosylation sites that contribute to its high carbohydrate content (approximately 45% of its molecular weight).
• Post-Translational Modifications: Glycosylation is the primary post-translational modification, influencing its biological activity and half-life in the bloodstream.

Classification and Subtypes:

• Family: ORM1 is part of the lipocalin family, a group of proteins known for their ability to bind small hydrophobic molecules.
• Isoforms: Various glycoforms of ORM1 exist, differing in their glycosylation patterns, which can affect their function and interaction with other molecules.

Function and Biological Significance:

• Acute-Phase Reactant: ORM1 is a major acute-phase protein, with its plasma concentration rising significantly during acute inflammation, infection, and tissue injury.
• Immune Regulation: ORM1 modulates immune responses, exhibiting anti-inflammatory properties by inhibiting neutrophil and lymphocyte function, reducing the production of pro-inflammatory cytokines, and altering the immune response.
• Drug Binding: ORM1 can bind various drugs, particularly basic (cationic) and neutral drugs, affecting their distribution and availability in the body. This property makes it important in pharmacokinetics and pharmacodynamics.
• Transport Protein: As a member of the lipocalin family, ORM1 can transport small hydrophobic molecules in the bloodstream.

Interactions:

• Immune Cells: ORM1 interacts with immune cells, modulating their activity and the overall immune response.
• Cytokines: It is involved in the regulation of cytokine activity, particularly during the acute-phase response.
• Drugs: ORM1 binds to various pharmaceutical compounds, affecting their plasma concentration and therapeutic efficacy.

Clinical Issues:

• Inflammatory Conditions: Elevated ORM1 levels are a marker of acute and chronic inflammatory conditions, including infections, autoimmune diseases, and trauma.
• Liver Disease: As ORM1 is synthesized in the liver, its levels can be affected by liver function. Decreased levels may indicate liver dysfunction.
• Cancer: Changes in ORM1 levels have been observed in various cancers, where it may play a role in tumor progression and immune evasion.
• Drug Interactions: ORM1's drug-binding properties can influence the pharmacokinetics of medications, necessitating dose adjustments in patients with elevated ORM1 levels due to acute-phase responses.

Summary:

Alpha-1-Acid Glycoprotein (ORM1) is a key acute-phase protein involved in modulating immune responses, binding drugs, and transporting small molecules in the bloodstream. Its levels increase significantly in response to inflammation, infection, and tissue injury, making it an important biomarker for these conditions. ORM1 interacts with immune cells and cytokines, exhibiting anti-inflammatory effects and influencing drug pharmacokinetics. Clinically, ORM1 is significant in the context of inflammatory diseases, liver function, cancer, and medication management. Understanding its role and regulation is crucial for diagnosing and treating various medical conditions.