Understanding Transplants, Immunity, and Disease Prevention

Posted on Feb 20, 2025 in Biology

Transplants and Donations

Transplants: Diseased or injured organs, tissues, or cells are replaced with healthy ones from a donor.

The donor can be another person, the same person, or an animal.

Donations:

• Cells: Reproductive cells or stem cells from embryos and umbilical cord blood.
• Tissue: Blood transfusion.
• Organs: Heart, liver, kidneys.

Transplant Complications

Rejection: Immune system response from the host.

Infection: Organ health is analyzed.

Immune Response

Non-Specific Immune Response

If pathogens cross the surface barriers, the second line of defense is activated.

Phagocytes: Some white blood cells perform the same response for all pathogens.

Specific Immune Response

If the second line of defense is not enough to stop a pathogen, a third line of defense is activated. Lymphocytes (some white blood cells) perform a specific response.

Lymphocytes: Recognize antigens, pathogens, or pathogen structures (proteins, polysaccharides, or lipids) that are foreign to the body.

Antigens: Activate lymphocytes that respond by producing antibodies (proteins) that neutralize antigens in pathogens.

• T-cells: Recognize and destroy cells containing antigens (infected cells).
• B-cells: Produce antibodies specific to the antigen that activated them.

*Some T and B cells become memory cells, remaining in the body for life. If the same antigen or pathogen invades again, memory cells remember and provide faster immunity to that disease. If the pathogen’s features change, the memory cells may be unable to recognize it, and the disease can occur again (e.g., the flu).

Disease Prevention

Prevention

• Personal and environmental hygiene: Wash hands before eating and after sneezing or coughing; keep living areas clean.
• Sexual health: Use condoms. Regular gynecologist visits.
• Food hygiene: Handle food properly and avoid food poisoning.
• Preventive measures for traveling: Vaccinations, insect repellent, bottled water, long sleeves and long trousers, mosquito nets.
• Pet care: Keep pets clean and vaccinated.
• Hygiene of sanitary workers
• Vaccination: Biological preparations made up of attenuated or dead forms of toxins, viruses, or bacteria. Provide immunity by preparing the body to react as though it is being attacked. The body produces specific antibodies against the disease and memory cells that will stay in the body and provide immunity for the future. Vaccination schedule for children up to 14 years old.

Pathogen Treatments

Non-Infectious Diseases

• Risk factor: Unbalanced diet
• Healthy habits: Use suitable light
• Environmental factors: Protect eyes and skin from the sun
• Risky behaviors: Exercise, sleep, and rest