MLT 115 Les 2 pt 2: BRMs and Complements

Overview of Immunology Concepts

  • Exam Preparation

    • Confidence expressed in students' readiness for Exam One.

    • Emphasis on understanding core concepts rather than worrying about extraneous issues.

Complement System

  • Definition of Complement

    • Increased complement levels are considered acute phase reactants, often not indicative of specific diagnoses.

    • C3 and C4 are often the complements that rise with inflammation

    • Decreased complement levels mean that the complement is missing a component. These are linked to increased susceptibility to infections. Oftentimes C2 is the one that is missing.

    • Neisseria gonorrhea is a particular infection that people are more susceptible to when complement levels are decreased

  • Mechanisms of Decreased Complement Levels

    • Excessive Activation and Depletion

    • Complement can be excessively activated and subsequently depleted in the body.

    • Genetic Deficiencies

    • The absence of a complement component, primarily C2, is often genetic.

    • C2 deficiency correlates with an immunodeficiency.

  • Consequences of C2 Deficiency

    • Leads to heightened vulnerability to certain infections, particularly:

    • Gonorrhea

    • Streptococcal infections

    • Implications:

    • Inability of bacteria to be opsonized due to lack of complement, leading to loss of lytic activity and phagocytosis.

Immunology Teaching Approach

  • Role of the Course

    • Focuses on understanding the production of antibodies and measuring responses against diseases rather than a comprehensive study of immunology.

    • Acknowledgment of the complexity and interest in immunology.

Biological Response Modifiers (BRMs)

  • Definition of Biological Response Modifiers

    • Substances that assist the immune system, acting like reinforcements.

    • Importance of understanding different classes of BRMs.

  • Types of Biological Response Modifiers

    • 1. B cells

    • Function: Produce antibodies.

    • 2. T cells (referred to as T Lymphocytes)

    • Involved in antigen presentation and secretion of key immune substances:

      • Interleukins: Facilitate cell-to-cell communication.

      • Colony Stimulating Factors: Lead to the production of neutrophils or monocytes depending on immune needs.

      • Interferon: Critical for antiviral defense and previously primary treatment for hepatitis C.

      • Tumor Necrosis Factor (TNF): Natural defense against tumors, but insufficient alone to control tumor size.

    • 3. Natural Killer Cells

    • Produce interferon alpha (IFN-alpha) and are important in combating infections.

    • 4. Monocytes and Macrophages

    • Produce multiple cytokines including TNF and interleukins, contributing significantly to immune responses.

Clinical Implications of BRMs

  • Drug Applications of Biological Response Modifiers

    • Use of monoclonal antibodies for targeting specific tumors instead of treating the whole body with toxic substances:

    • Aims to enhance therapeutic effectiveness while minimizing side effects.

    • Recognition of the therapeutic potential of BRMs for a range of diseases.

Future Focus and Review

  • Upcoming Topics

    • Next class will involve discussions on cytokines and a review of related materials.

    • Students are encouraged to familiarize themselves with concepts surrounding complement and related immunology topics as these will be central to upcoming exams.

  • Exam Preparation Specifics

    • All exam questions to derive from a provided key paper.

    • Students advised to understand and describe bacterial colonies observed in lab work, despite the complexity of the current material.

Conclusion

  • Stress on the necessity of comprehensive understanding of the material for future application and exam readiness. Emphasis on the integration of theoretical concepts with practical lab results to solidify comprehension of immunology.