ABSTRACT
Bioengineers have contributed to biocompatibility research. Many materials have been designed, synthesized, and characterized by use of various analytical instruments. The blood compatibility of materials has been studied by focusing on the blood-material interfacial reactions. Although much information has been accumulated regarding such local reactions, understanding of biocompatibility is still limited. A more global approach to study is needed. A new approach to understanding biocompatibility is proposed and discussed. Three points are stressed: interaction within body's defense system and its effect on blood-material reactions; induction of a systemic reaction by a local reaction, which then affects the blood-material interaction; the time sequence of such interactions between local and systemic reactions. To establish a logical approach to study biocompatibility is most important at this moment for the future progress in biocompatibility research.
Subject(s)
Biocompatible Materials , Biocompatible Materials/adverse effects , Biocompatible Materials/immunology , Blood Coagulation , Blood Platelets/physiology , Blood Proteins/metabolism , Complement Activation , Factor XII/physiology , Fibrinolysis , Humans , Immunity , Kallikreins/physiology , Leukocyte Count , Membranes, Artificial , Oxygen/administration & dosage , Plasma Exchange , Protein DenaturationABSTRACT
Plasmapheresis is generally recognized as a "black box" therapy. Factors effecting the immunomodulating influence of plasmapheresis and their impact on the clinical results include the disease state and stage, associated drug and medical therapies, and the methodology of plasmapheresis. The immunomodulating influence of the methodology of plasmapheresis, including duration of treatment, frequency of treatment, equipment type, materials choice, anticoagulant choice, and volume replacement versus selective removal, has a profound impact on the clinical results. Limitations in the design of controlled trials emphasize the importance of assessing the events occurring within and as a result of the individual black box utilized in plasmapheresis therapy. The analysis and understanding of the immunomodulating influences of the "black box" will prove to be very valuable in the development of better technologies for patient care.
Subject(s)
Immune System Diseases/immunology , Plasmapheresis , Biocompatible Materials/immunology , Blood Volume , Citrates/pharmacology , Complement Activation , Heparin/pharmacology , Humans , Immune System Diseases/therapy , Immunity, Cellular , Interleukin-1/immunology , Plasmapheresis/instrumentation , Plasmapheresis/methodsABSTRACT
The histological fate of an injectable form of type I bovine dermal collagen (Zyderm collagen implant) in the human dermis and subcutaneous tissue has been studied. Sequential biopsies were analyzed by hematoxylin-eosin and Weigert's stains, by immunofluorescence (using a highly specific rabbit anti-Zyderm collagen antibody and a specific anti-human type III collagen antibody), and by electron miscroscopy. The results of this study suggest that the bovine implant material stimulates a host response resulting in implant degradation and replacement by newly generated host collagen.
Subject(s)
Biocompatible Materials , Collagen/therapeutic use , Adult , Aged , Animals , Biocompatible Materials/immunology , Biopsy , Cattle , Collagen/immunology , Collagen/metabolism , Drug Implants , Fluorescent Antibody Technique , Humans , Immunoglobulin G/analysis , Inflammation/pathology , Male , Microscopy , Microscopy, Electron , Skin/immunologyABSTRACT
This paper relates materials science, physiology, biochemistry, pharmacology, immunology, pathology and toxicology to the study of metabolism of degradation and corrosion products arising from tissue/material interactions. The mechanisms of absorption and distribution of released substances, either in solution or as particles, are considered together with their related chemistry. The importance of immune processes is discussed and their potential use for immunological analysis is illustrated by reference to nickel and mercury as used in the oral cavity.
Subject(s)
Biocompatible Materials/toxicity , Absorption , Animals , Biocompatible Materials/immunology , Biodegradation, Environmental , Chemical Phenomena , Chemistry , Corrosion , Hypersensitivity/immunology , Mercury/toxicity , Nickel/toxicity , Tissue DistributionABSTRACT
Polydimethylsiloxane has been considered immunologically inert, and previous work seems to have established that the production of circulating antibodies does not occur in response to its implantation. We have investigated the possibility of a cellular immune response to implanted silicone. We have observed histologically that the cellular response to polydimethylsiloxane in sensitized guinea pigs is consistent with a cellular immune reaction. Further studies with EM and XES have demonstrated intracellular silicon in the Golgi apparatus, rough endoplasmic reticulum, and at both ends of cytoplasmic bridges between macrophages and lymphocytes. All of these findings fit with the hypothesis that the cells are processing a silicon-containing complex as an antigen. Finally, macrophage migration inhibition studies have shown evidence of a cellular immune phenomenon. Further studies are planned to characterize the nature of the sensitizing complex and to attempt to confirm the migration inhibition studies in vivo.
