Activity 1
- Since inflammation is among the body’s nonspecific defense mechanisms, its response to a traumatized area is similar to that of the responses to damages due to burns, radiation, or viral invasion. Its process occurs in three basic steps:
- Vasodilation and increased permeability of blood vessels allow more blood to flow through the affected region and allows for the elimination of microbial toxins and dead cells;
- Phagocytes emigrate from the bloodstream into the interstitial fluid in order for inflamed tissue monocytes to grow into wandering macrophages that augment the phagocytic activity of any fixed macrophages existing in the tissue; and,
- Tissue repair occurs when macrophages die, resulting in the formation of pus, a collection of dead tissue cells and fluid which could reach the body's surface or drain into an interior cavity and disperse. At that point, the tissue experiences remodeling to restore its previous features.
- Humoral immunity operates by the production of antibody molecules in response to an antigen via a mechanism that requires chemicals found in body fluids such as humor. Plasma cells produce antibodies that act as a bridge between the humoral and cellular immune responses. Antigens attach to antigen receptors on B cells, alerting them and activating helper T cells. Binding antigen and helper T cell signals encourage B cell growth and differentiation into plasma cells that release particular antibodies. By clinging to pathogens and blocking their destructive effects, these antibodies can neutralize them. Pathogens can also be coated, allowing accessory cells to consume and destroy them by opsonization. Antibodies also have the ability to activate the complement system, which can significantly boost opsonization and directly kill some bacterial cells.
References:
Janeway, C. A., Jr. (2001). The humoral immune response. Immunobiology - NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK10752/
LibreTexts. (2022, April 9). 13: Humoral immunity. Biology LibreTexts. https://bio.libretexts.org/Bookshelves/Microbiology/Microbiology_(Kaiser)/Unit_6%3A_Adaptive_Immunity/13%3A_Humoral_Immunity
Tortora, G. J., & Derrickson, B. H. (2017). Tortora’s Principles of Anatomy & Physiology. Wiley.