Human body response to biomaterial implantations

In conclusion, all five themes have been explored in depth. The cell communication and the immune system is a significant example of how some of the themes can be connected. Because the cell communication between neutrophils and macrophages lead to an immune system input to the body response to a material implant. The example of dental implant shows that the inflammatory at the wound site where a material is implanted could be a form of body response. The strength of cell adhesion by the amount of the vinculin in focal adhesion, together with the amount of active cells on biomaterial in the MTT assay are both key elements to minimise a body’s rejection to the implantation of biomaterials. Hence, there will be a strong cell adhesion on the biomaterials. Coating on biomaterials is mentioned twice in the blogs because it determines the strength of a biomaterial’s adhesion to a cell. Although the blog on cell adhesion has shown that coating of graphene increases the strength of focal adhes

There is a bit of both from the immune system and blood in the contribution of a body’s response to a biomaterial implanted on its own or as part of a biomedical device. Following from the blog about cell communication, this blog looks into how the immune system and blood interaction contribute to the soft tissue wound healing process after dental implant.[5] The role of immune system is explored in the inflammatory part of the tissue healing after dental implant. Immune system includes a complement system and macrophages. The complement system damages bacterial cells with glycoproteins while macrophages form giant foreign body cells in response to the implant.  As the vasodilative histamine is released from platelets in the damaged blood vessels, the blood flow is increased, velocity of the flow is decreased which introduces the swelling and warming around the wound. This leads to inflammation which is a body response to the wound created by the implantation of a biomaterial. It is no

  Adverse effect is similar to side effect but is more severe and undesirable. Biomaterials can cause adverse effect when implanted because of the toxicity and degradation. Examples of the effect are such, inflammation, toxicity and allergy. This paragraph is about an example of the adverse effects by titanium dioxide nanoparticles (TiO 2 ) and the method to avoid such effect.[4] TiO 2 is a next gen biomaterial and is broadly used in sunscreen. TiO 2 is used because it is absorbs huge amount of UV radiation due to its large surface area to volume ratio. But TiO 2 induces oxidative damage by its cytotoxicity. Because the absorbing UV lights generates reaction oxygen species (ROS). Together with the large surface area due to TiO 2 being a nanoparticle, this further increases the amount of ROS which is the origin of TiO 2 ’s adverse effect. Because ROS causes genetic damage and damage to cell functions after TiO 2 penetrating through cell membranes. In an experiment of incubating rutile

When cells adhere to each other, a transmembrane protein – cadherin helps the adhered cells to communicate within each other. Since there is a surface tension in the adhered cells which affects the cell-cell contact. Cadherins trigger signals to reorganise the actomyosin cytoskeleton from each cells to reduce the tension and increase the contact surface area. Another way of cell communication is by cell signalling molecules when cells are apart from each other. There are a few signalling types but they all follow the same principle. A cell gives out a signalling molecule which binds to the receptor on another cell. The signalling molecule activates a receptor at a specific area of the surface. To transduce the signal into the target cell, a secondary, intracellular signalling molecule is needed. This could be any protein and ions, etc. Eventually, there will be an end point which is a cellular activity, such as, cytoskeleton reorganisation. In fact, cell communication complements wit

Biocompatibility is defined as the degree of “how well a material lives” in a human body after being implanted. Therefore, biomaterials go through in vivo or in vitro tests in order to be implanted. In vivo tests are on living organisms while in vitro tests are on a test tube or petri dish. This blog mentions an example from each type of the tests. Firstly, there is the MTT assay which measures the biocompatibility on 3 materials, e.g. Perspex, Delrin and Polyvinyl chloride (PVC). MTT assay is an in vitro test because the cells – HaCaT that are used to test the biocompatibility are seeded onto biomaterial disks under a controlled condition. These cells are an immortalised epithelial cell line which is capable of skin keratinocyte differentiation. It is called the MTT assay because MTT is a reagent (MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide) added to measure cell metabolism by turning into purple on metabolically active cells. The change in absorbance at 570nm

  Cell adhesion is when a cell binds to an adjacent cell or a surface via the molecules on the cell surface. When a biomedical product is implanted into a body, there are 3 ways of cell adhesion to the biomaterials in the product. For example, anchoring junction, close contact and extracellular matrix contacts. For anchoring junction, Cells adhere to the extracellular matrix (ECM) film on the biomaterial with a gap of 10 to 15nm which gives a strong adhesion. To connect the cells itself and the ECM film on the biomaterial, a transmembrane protein – Integrin is needed. Integrin connects the fibronectin in ECM to different cytoskeleton filament depending on the type of junction. A type of anchoring junction – focal adhesion has the actin filament connected. There are subsequent behaviours. For focal adhesion, cells involved respond to the stiffness of adhered surface because mechanical forces are transduced to the actin filament in the cytoskeleton of the cell. The response could be incr

  Bioengineering is a combination of engineering and biology that has a range of application. This form of engineering varies from designing products that mimic the functions of certain body parts to the manufacturing of medicines. This website consists of blogs that describe the cell and human biology of biomaterials after being implanted into a human body. As long as a material is compatible with the living system of a human, it is considered as a biomaterial. Therefore, biomaterial could be metal, polymers, ceramics, etc. Biomaterials applications consist of medical implants, promoting healing and regenerating of human tissue and drug deliveries. Biomaterials are used in biomedical products such as, heart valves, hip joint replacements and dental implants. [1] This website  explains how the body responds to the implantation of biomaterial and the examples of specific biomaterials used in the different body sites. There will be five blogs on this website on cell adhesion, cell commun