Ultrastructural Location and Interactions of the Immunoglobulin Receptor Binding Sequence within Fibrillar Type I Collagen

• Published in: International journal of molecular sciences 2020-06, Vol.21 (11), p.4166
• Main Authors: Zhu, Jie, Madhurapantula, Rama S, Kalyanasundaram, Aruna, Sabharwal, Tanya, Antipova, Olga, Bishnoi, Sandra W, Orgel, Joseph P R O
• Format: Article
• Language: English
• Subjects: Animals; Antibodies; Atomic force microscopy; BASIC BIOLOGICAL SCIENCES; Binding; Binding Sites; Blood vessels; Bronchi; Bronchus; Cartilage; Cell-mediated immunity; Collagen; Collagen (type I); Collagen Type I - chemistry; Collagen Type I - immunology; Collagen Type I - metabolism; Collagen Type I - ultrastructure; Collagenase; Discoidin Domain Receptor 1 - metabolism; Domains; Elastic Modulus; Extracellular matrix; Fibrils; Fibronectin; Fibrosis; Fourier Analysis; Gold - chemistry; Immunoglobulins - immunology; Immunogold-labeling; Ligands; lung disease; Lungs; Major histocompatibility complex; MHC class I; Microscopy, Atomic Force; Nanomechanical properties; Peptides; Peptides - metabolism; Rats, Wistar; Receptors, Immunologic - immunology; Scattering, Small Angle; Tendons; X-Ray Diffraction; X-rays
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms21114166

Collagen type I is a major constituent of animal bodies. It is found in large quantities in tendon, bone, skin, cartilage, blood vessels, bronchi, and the lung interstitium. It is also produced and accumulates in large amounts in response to certain inflammations such as lung fibrosis. Our understanding of the molecular organization of fibrillar collagen and cellular interaction motifs, such as those involved with immune-associated molecules, continues to be refined. In this study, antibodies raised against type I collagen were used to label intact D-periodic type I collagen fibrils and observed with atomic force microscopy (AFM), and X-ray diffraction (XRD) and immunolabeling positions were observed with both methods. The antibodies bind close to the C-terminal telopeptide which verifies the location and accessibility of both the major histocompatibility complex (MHC) class I (MHCI) binding domain and C-terminal telopeptide on the outside of the collagen fibril. The close proximity of the C-telopeptide and the MHC1 domain of type I collagen to fibronectin, discoidin domain receptor (DDR), and collagenase cleavage domains likely facilitate the interaction of ligands and receptors related to cellular immunity and the collagen-based Extracellular Matrix.