Chapter 34: Drugs for Immune System Modulation

Overview

• Focus on immunomodulators: drugs or therapies affecting body defenses.
• Immunomodulators can stimulate or suppress the immune system.
• Non-specific innate defenses include physical barriers, phagocytes, natural killer cells, fever, interferons, and inflammation.
• Important figure: Figure 34.1 on page 487, detailing specific cell functions.

Immunity Types

Specific Humoral Response

• B cells and plasma cells: Initiated when an antigen encounters a B cell.
• Antigens: Viruses, bacteria, fungi, protists, or toxins.
• Plasma cells: Secrete antibodies (immunoglobulins) that neutralize foreign agents and mark them for destruction.
• Memory B cells: Speed future defenses against specific antigens.

Active Immunity

• Exposure to antigens or vaccination produces active immunity.
• Vaccines: Induce antibody production without illness.

Passive Immunity

• Transferred antibodies from one person to another.
  • Maternal antibody transfer via placenta.
  • Immunoglobulin treatments.
  • Treatment for diseases like botulism, tetanus, rabies.
• Immunosuppressed patients: May require passive immunity.

Vaccination

• Immunization agents: Vaccines introduce foreign proteins to trigger immune responses.
• Types of vaccines: Live (attenuated), killed, toxoid, recombinant.
• Hepatitis B vaccine: Prototype for vaccines.
  • Adverse effects: Pain at injection site, mild fever.
  • Contraindications: Hypersensitivity to yeast.

Specific Cell-Mediated Response

Helper T Cells

• Stimulate both humoral and cell-mediated immunity.
• Cytokines: Released by helper T cells, activate B cells and cytotoxic T cells.
• Memory cells: Confer future immunity.

Cell-Mediated Response

• Targets infected body cells due to infections or cancer.
• Cytokines: Regulate immune response intensity and duration.

Immunostimulants

• Interferons and interleukins: Boost immune system.
• Interleukin uses: Treat cancers, stimulate platelet production.
• Interferon uses: Treat leukemia, AIDS, Hepatitis B/C.

Prototype Drug: Interferon Alpha-2B

• Use: Treat cancers and viral infections.
• Adverse effects: Flu-like syndrome, depression.
• Contraindications: Not for neonates due to benzyl alcohol.

Immunosuppressants

• Purpose: Inhibit immune system for treating autoimmune disorders and preventing organ transplant rejection.
• Risks: Toxic to bone marrow, increased infection risk.

Prototype Drug: Cyclosporine

• Use: Inhibits helper T cells to prevent transplant rejection.
• Adverse effects: Severe infection, cancer, decreased urine output.
• Black Box Warning: May cause serious disorders.

Organ Transplants

• Rejection: Triggered by antigens on transplanted organs.
• Acute rejection: Rapid, humoral response.
• Chronic rejection: Slower, occurs over months/years.

Autoimmune Disorders

• Examples: Rheumatoid arthritis, lupus.
• Treatment: Immunosuppressants with serious adverse effects.

Key Nursing Responsibilities

• Vaccinations: Assess risks, educate on schedules, monitor for adverse effects.
• Immunostimulants: Hydration, mental status monitoring.
• Immunosuppressants: Monitor vital signs, lab tests, infection signs, and secondary malignancy development.