Microorganisms: Pharmaceutical and Immunological Uses
Microorganisms in the Pharmaceutical Industry
Microorganisms play a crucial role in the pharmaceutical industry. Antibiotics, for instance, are antimicrobial chemical compounds synthesized by fungi and bacteria.
Fleming’s accidental discovery of penicillin, by contaminating a Petri dish, highlighted this. He noted that the fungus secreted a substance that destroyed bacterial colonies. Penicillin is particularly effective against Gram-positive bacteria. Later, streptomycin was discovered, proving effective against both Gram-positive and a large number of Gram-negative bacteria, including tuberculosis.
Some fungi and bacteria generate greater amounts than needed.
- Production occurs in aerobic media and requires a cheap cultivation medium.
- The main enzymes produced are proteases, used in bioactive detergents.
- Glucoamylases and amylases are used for obtaining glucose from starch.
Microbial Genetic Engineering
Microbial genetic engineering involves introducing the gene that controls the production of a specific molecule into the genome of a bacterium. The bacteria carry this DNA fragment, and the cloned gene is reproduced and received. Microorganisms are very useful for obtaining drugs, vaccines, and hormones.
Important molecules for medicine, such as hormones and vaccines against cholera, rabies, etc., are obtained through these techniques. Microorganisms are also grown as food supplements. Yeasts and bacteria are referred to as single-cell protein. The majority of vitamins added to food are produced in laboratories by microbial fermentation.
Another application is the manufacture of biopesticides. Chemical pesticides are toxic and tend to accumulate in leaves, fruits, or water, with negative impacts on the environment. Certain bacilli produce insoluble proteins in the form of crystalline inclusions, affecting many insect larvae.
The Immune System and Cancer
The immune system inhibits cancer development. Cancer cells present surface antigenic molecules different from those of normal cells. Ideally, these are recognized as foreign, triggering a defense response.
This defense develops through a cellular immune response. Cytotoxic T cells bind to cells with altered antigens, destroying them. Helper T cells strengthen and activate cytotoxic macrophages. They bind to cancer cells, activating NK cells and complementing the immune response.
Causes of Immune System Ineffectiveness
- Cancer cells have few MHC molecules, making it difficult for cytotoxic lymphocytes to recognize them.
- Cancer cells have the ability to hide their antigens.
- The immune response can be slow relative to the rate of tumor growth, especially with a large number of cancer cells.
Immunotherapy
Immunotherapy treatments include:
- Nonspecific Cytokines: These proteins are produced by the body in response to processes that activate lymphocytes and macrophages. Lymphocytes are removed and exposed to interleukins.
- Passive Immunization with Monoclonal Antibodies: These are pure forms of antibodies capable of recognizing a single antigen. After injecting a mouse, hybridomas were observed that constantly divide and produce large quantities of a single antibody.
- Adoptive Immunotherapy: Cells are extracted, exposed to tumor antigens *ex vivo*, and stimulated. These cells are then injected to respond to the tumor.
- Cell Gene Therapy: Genes that confer virulence are deleted, and therapeutic genes are inserted.