lecture recording on 07 March 2025 at 13.55.07 PM

Immune Rejection

• Organ and Tissue Rejection

  • Occurs when the immune system attacks transplanted organs/tissues as foreign.

  • Happens even with perfect matches due to innate immune responses.

  • Auto-transplants are less likely to be rejected since they come from the same individual.

• Anti-Rejection Medication

  • Transplant recipients must take anti-rejection drugs to prevent organ rejection.

  • These drugs have significant side effects.

  • Recipients require a cocktail of these medications for life.

    • E.g., heart transplant patients are injected with anti-rejection drugs post-surgery.

• Rejection Outcomes

  • If a transplant is rejected, the patient might return to the waiting list for another organ.

  • In some scenarios, temporary nonintravenous hearts can be used until a suitable heart is found.

Allergies

• Definition

  • Allergies are hypersensitivity reactions to typically harmless substances (antigens).

  • The body overreacts, leading to potentially life-threatening conditions like anaphylaxis.

• Anaphylaxis

  • Severe allergic reaction that causes symptoms such as swelling and difficulty breathing.

  • Can be deadly if not treated rapidly.

• Overdiagnosis and Treatment

  • In the late 20th century, there was increased caution with food consumption by children, leading to heightened allergy rates.

  • Current research suggests small exposures may help children develop tolerance to allergens rather than sensitization.

• Changing Sensitivities

  • Individuals may develop new allergies or lose previous ones due to bodily changes (e.g., during puberty, menopause).

  • Allergies can vary by region; individuals may have less hay fever in different environments.

Allergy Management

• EpiPen

  • An emergency treatment for severe allergic reactions containing epinephrine.

  • Expedites widening of blood vessels and alleviates symptoms of anaphylaxis.

  • Can be used even if someone else’s EpiPen is available in emergencies.

• Antibodies and Reactions

  • IgE antibodies are primarily responsible for allergic reactions.

  • Airborne allergies affect individuals through inhalation of allergens such as dust.

• Difference between Allergy and Sensitivity

  • Allergies involve immune responses, while sensitivities (like lactose intolerance) are often non-immune reactions.

Autoimmunity and Immune Responses

• Autoimmune Diseases

  • Result from the immune system attacking the body's own tissues.

  • The distinction between allergies and autoimmune diseases lies in their causes and reactions.

• Fight or Flight Response

  • In stressful situations, individuals may have exaggerated reactions due to overactive immune responses.

  • This can lead to differences in perception and response to emergencies, influencing behaviors in crisis situations.

Miscellaneous Insights

• Food Reactions

  • Food intolerances can lead to symptoms like nausea without forming the typical allergic reactions (hives, swelling, etc.).

• Environmental Factors

  • Allergies and sensitivities can involve chemical exposures and dietary differences across locations.

• Vivid Dreams and Medications

  • Some medications can alter sleep patterns, induce vivid dreams, or nightmares, possibly due to brain chemistry changes or sleep disturbances.

Conclusion and Future Research

• Continued exploration of allergies, immune responses, and treatments is crucial as new data suggests changing trends in allergic reactions and tolerance in populations.