title: Covalent linking of proteins and cytokines to suture: enhancing the immune response of head and neck cancer patients.
abstract: BACKGROUND
  The immune system of advanced stage head and neck cancer patients is frequently suppressed. Poor immune function has been correlated with poor clinical outcome. Immunotherapeutic strategies have been previously attempted in an effort to enhance immune function and improve survival. Previous studies have shown surgical suture can be transformed into an immune stimulant capable of activating the T lymphocytes of cancer patients. The development of a process for covalently linking proteins and cytokines to suture could have enormous potential for the in vivo manipulation of the immune system.
  
  
  OBJECTIVE
  We hypothesize proteins and cytokines can be covalently linked to surgical suture while preserving their functional properties.
  
  
  METHODS
  Prospective study testing normal donor and head and neck squamous cell carcinoma (HNSCC) patient lymphocytes.
  
  
  METHODS
  Polyester suture was acid hydrolyzed followed by reacting with 1-ethyl-3(-3-dimethylamino propyl carbodiimide) (EDAC) to create a suture-EDAC intermediate. Next, selected proteins (horseradish peroxidase [HRP] or bovine serum albumin [BSA]) or cytokines (interleukin [IL]-2 or interferon [IFN]-gamma) were reacted with the suture-EDAC intermediate to test the covalent linkage of the selected protein or cytokine to suture. Functional activity of the linked proteins was measured spectrophotometrically. The linking of cytokines to suture was tested by stimulating normal donor peripheral blood lymphocytes (PBL) or HNSCC patients' lymphocytes. The functional activity was confirmed by proliferation, enzyme linked immunoadsorbent assay (ELISA), and phenotype expression of T cells. RESULTS The conditions for optimally linking a protein to polyester suture were defined using HRP as a model protein. HRP retained its enzymatic activity. The optimal conditions for linking IL-2 or IFN-gamma were defined. The covalently linked cytokines retained their immune enhancing properties for stimulating PBL and lymph node lymphocytes (LNL) from HNSCC patients to proliferate, generate a TH1 immunologic profile of cytokines (IL-2, IL-12, IFN-gamma), and stimulate T lymphocytes.
  
  
  CONCLUSIONS
  This is the first report to demonstrate that cytokines can be covalently linked to surgical sutures and retain their immune-stimulating properties. Proteins linked to suture also retained their enzymatic activity. The clinical implications of functionally active cytokines or proteins linked to surgical suture may be very significant in the future for manipulating the immune system in vivo or enhancing wound healing.
authors: Department of Otolaryngology/Head and Neck Surgery, University of California Irvine College of Medicine, Orange 92868, USA. tshibuya@uci.edu
authors: Terry Y
authors: TY
authors: Shibuya
authors: Sanghun
authors: S
authors: Kim
authors: Kevin
authors: K
authors: Nguyen
authors: Parag
authors: P
authors: Parikh
authors: Ashish
authors: A
authors: Wadhwa
authors: Chad
authors: C
authors: Brockardt
authors: Johnny
authors: J
authors: Do
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000276:immunology; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use*; D002294:Carcinoma, Squamous Cell / Q000276:immunology / Q000378:metabolism / Q000628:therapy; D020099:Coated Materials, Biocompatible; D004797:Enzyme-Linked Immunosorbent Assay; D005240:Feasibility Studies; D005260:Female; D006258:Head and Neck Neoplasms / Q000276:immunology / Q000378:metabolism / Q000628:therapy; D006735:Horseradish Peroxidase / Q000276:immunology / Q000378:metabolism; D006801:Humans; D006868:Hydrolysis; D007111:Immunity, Cellular; D007150:Immunohistochemistry; D007167:Immunotherapy / Q000379:methods; D007371:Interferon-gamma / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use*; D007376:Interleukin-2 / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use*; D008198:Lymph Nodes / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status; D010641:Phenotype; D011091:Polyesters / Q000627:therapeutic use; D011446:Prospective Studies; D012710:Serum Albumin, Bovine / Q000276:immunology / Q000378:metabolism; D013537:Sutures; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology*; D013997:Time Factors; D014945:Wound Healing / Q000187:drug effects / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000970:Antineoplastic Agents; D020099:Coated Materials, Biocompatible; D007376:Interleukin-2; D011091:Polyesters; D012710:Serum Albumin, Bovine; D007371:Interferon-gamma; D006735:Horseradish Peroxidase