Cinoxacin

An article about the antibiotic Cinoxacin

Engineered Monoclonal Antibodies

Diagram of engineered monoclonal antibodies

Engineered monoclonal antibodies are a class of biological therapies that are designed to target specific antigens on the surface of cells. These antibodies are produced using recombinant DNA technologies and are used in the treatment of various diseases, including cancer, autoimmune disorders, and infectious diseases.

Structure and Function

Monoclonal antibodies are composed of two identical heavy chains and two identical light chains, forming a Y-shaped molecule. The tips of the "Y" contain the antigen-binding sites, which are highly specific to the target antigen. This specificity allows monoclonal antibodies to bind to their target with high affinity, blocking or modulating the function of the antigen.

Types of Engineered Monoclonal Antibodies

There are several types of engineered monoclonal antibodies, each designed for specific therapeutic purposes:

• Chimeric antibodies: These antibodies are composed of murine (mouse) variable regions and human constant regions. They are less immunogenic than fully murine antibodies.

• Humanized antibodies: These antibodies are mostly human, with only the antigen-binding sites derived from murine sources. This reduces the risk of immune reactions.

• Fully human antibodies: These are entirely human in origin, produced using transgenic mice or phage display technologies.

• Bispecific antibodies: These antibodies are engineered to bind two different antigens simultaneously, offering unique therapeutic mechanisms.

Applications in Medicine

Engineered monoclonal antibodies have revolutionized the treatment of many diseases:

• Cancer therapy: Monoclonal antibodies can target specific tumor antigens, leading to direct tumor cell killing or recruitment of immune cells to attack the tumor.

• Autoimmune diseases: By targeting specific components of the immune system, monoclonal antibodies can reduce inflammation and tissue damage in diseases such as rheumatoid arthritis and multiple sclerosis.

• Infectious diseases: Monoclonal antibodies can neutralize pathogens or their toxins, providing passive immunity or enhancing the host's immune response.

Production

The production of engineered monoclonal antibodies involves several steps:

1. Antigen identification: The target antigen is identified and characterized. 2. Hybridoma technology: B cells from immunized animals are fused with myeloma cells to create hybridomas that produce the desired antibody. 3. Recombinant DNA technology: Genes encoding the antibody are cloned and expressed in suitable host cells, such as Chinese hamster ovary cells. 4. Purification and formulation: The antibodies are purified and formulated for clinical use.

Challenges and Future Directions

While engineered monoclonal antibodies have shown great promise, there are challenges such as high production costs, potential for immune reactions, and the development of resistance. Ongoing research aims to improve antibody design, reduce immunogenicity, and enhance therapeutic efficacy.

Related Pages

• Monoclonal antibody therapy
• Biopharmaceutical
• Immunotherapy
• Hybridoma technology

Cinoxacin is a synthetic antibiotic belonging to the quinolone class. It was primarily used to treat urinary tract infections (UTIs) caused by susceptible strains of bacteria. Although it was once a common treatment, it has largely been replaced by newer antibiotics with improved efficacy and safety profiles.

Mechanism of Action

Cinoxacin works by inhibiting bacterial DNA gyrase, an enzyme critical for DNA replication and transcription. By interfering with this enzyme, cinoxacin prevents bacteria from reproducing and repairing themselves, leading to bacterial cell death.

Pharmacokinetics

Cinoxacin is administered orally and is well absorbed from the gastrointestinal tract. It is widely distributed throughout the body and is primarily excreted unchanged in the urine. This makes it particularly effective for treating infections of the urinary tract.

Clinical Uses

Cinoxacin was used to treat uncomplicated urinary tract infections caused by Escherichia coli, Proteus mirabilis, and other susceptible organisms. It was not effective against Pseudomonas aeruginosa or anaerobic bacteria.

Side Effects

Common side effects of cinoxacin included nausea, vomiting, and diarrhea. Some patients experienced photosensitivity, leading to increased risk of sunburn. Rarely, it could cause central nervous system effects such as dizziness and headache.

Resistance

Bacterial resistance to cinoxacin can develop through mutations in the genes encoding DNA gyrase or through efflux mechanisms that reduce drug accumulation in bacterial cells. The emergence of resistance has limited the use of cinoxacin in clinical practice.

History

Cinoxacin was introduced in the 1970s as one of the first quinolone antibiotics. It was a precursor to the development of more advanced quinolones, such as ciprofloxacin and levofloxacin, which have broader spectra of activity and improved pharmacokinetic properties.

Discontinuation

Due to the development of newer antibiotics with better safety and efficacy profiles, cinoxacin has been largely discontinued in many countries. It is no longer a first-line treatment for urinary tract infections.

Related pages

• Quinolone
• Urinary tract infection
• Antibiotic resistance

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  Cinoxacin