Scientific explanaition for Ig-like domain containing proteins:

  1. General characterization

The Immunoglobulin-like (Ig-like) domain is a protein domain that can be found in a variety of protein, including the immunoglobulin fold found in antibodies. The Ig-like domain is highly conserved throughout evolution, indicating its fundamental role in biological systems, and it can most commonly be found in the Immunoglobulin Superfamily (IgSP)1.

The Ig-like domain containing proteins (IGLDCPs) belong to a broad class of proteins that feature Ig-like domains. These domains are structurally similar to the immunoglobulin domains found in antibodies, and they are involved in a wide range of biological processes, including immune system functions, cell adhesion, and molecular recognition. Their prevailing presence in proteins that oversee cellular and molecular communication highlights their unique importance in the organism’s ability to maintain homeostasis.

  1. Structure

The Ig-like domains possess a distinct beta-sheet fold composed of 70-110 amino acids. This fold is comprised of two opposing anti-parallel beta-sheets, connected with a central disulfide bond. These domains are evolutionarily conserved and are present in a variety of proteins across different species2.

  1. Function

Ig-like domain containing proteins (IGLDCPs) take an integral part in regulating immune responses and maintaining immune homeostasis. They are part of the activation cascade for both the innate and adaptive immune response. These proteins, characterized by their Ig-like domains, play versatile roles in recognizing pathogens, facilitating cell signaling, and promoting the coordination of immune responses3,4.

IGLDCPs are considered checkpoint modulators, playing a crucial role in maintaining the balance of immune activation and inhibition, meaning they control the threshold necessary for activation, ensuring that the immune system responds appropriately while avoiding excessive or misdirected activity that could lead to autoimmunity or tissue damage.

Some mechanisms of action of the IGLDCPs are known (phagocytosis via ATP production, Inhibitory Signal Transduction, Modulation of Immune Synapse Formation, Modulation of Cytokine Production, etc), while there are still aspects of their mechanisms of action that are not fully known4.

4. Clinical significance

IGLDCPs are clinically significant due to their central role in regulating immune responses and maintaining immune homeostasis. Their involvement in key processes such as immune activation, inhibition, and cell signaling makes them important targets for therapeutic intervention in various diseases (cancer immunotherapy, autoimmune disease management, transplantation, and the treatment of chronic infections, etc)

5. Dietary supplements

IGLDCPs in dietary supplements are an emerging area of interest due to their potential health benefits, particularly in immune modulation, gut health, and overall wellness. Direct incorporation of specific IGLDCPs into dietary supplements is not yet widespread, and some supplements indirectly utilize components that contain these proteins, such as immunoglobulins derived mainly from colostrum.

While colostrum is a known supplement to contain Ig-like domain containing proteins, bioREPAIR shows high efficacy and superior functionality when compared to the available alternatives.

1 (A) Huang, Z., Li, S., & Korngold, R. (1997). Immunoglobulin superfamily proteins: Structure, mechanisms, and drug discovery. Biopolymers, 43(5), 367–382 (B) December 21, 1999 96 (26) 14672-14674 https://doi.org/10.1073/pnas.96.26.14672; Front Immunol. 2023; (C) 14: 1239146. doi: 10.3389/fimmu.2023.1239146 (D) https://doi.org/10.1146/annurev.iy.06.040188.002121

2 Basic Neurochemistry (Eighth Edition) Principles of Molecular, Cellular, and Medical Neurobiology 2012, Pages 165-179

3 Davis, S. J., & van der Merwe, P. A. (2006). The structure and ligand interactions of immunoglobulin superfamily cell surface molecules. Annual Review of Immunology, 24, 243-269; Barclay, A. N. (2003). Membrane proteins with immunoglobulin-like domains—a master superfamily of interaction molecules. Seminars in Immunology, 15(4), 215-223.

4 Meng JH, Chen CX, Ahmadian MR, Zan H, Luo KJ, Jiang JX. Cross-Activation of Hemi channels/Gap Junctions and Immunoglobulin-Like Domains in Innate-Adaptive Immune Responses. Front Immunol. 2022 Jul 15;13:882706. doi: 10.3389/fimmu.2022.882706. PMID: 35911693; PMCID: PMC9334851.