Тест: Understanding the Complement System in Immunity — 5 въпроса

1. Which of the following is a key component of the regulation mechanisms in the complement system?

A. Cytokines like IL-6 and TNF-alpha

B. Regulatory proteins such as DAF, factor H, and MCP

C. Antibodies targeting complement proteins

D. Enzymes involved in complement activation

Answer: (B)

Обяснение

The regulation mechanisms of the complement system primarily involve regulatory proteins such as decay-accelerating factor (DAF), factor H, and membrane cofactor protein (MCP), which prevent overactivation and protect host tissues. The source explicitly mentions these molecules as key components in regulation.

2. What is the complement system primarily understood as in innate immunity?

A. A set of immune cells that directly attack infected cells

B. A pathway of gene expression involved in antibody production

C. A collection of antibodies targeting specific pathogens

D. A group of plasma proteins that enhance immune responses and facilitate pathogen elimination

Answer: (D)

Обяснение

The complement system is defined as a group of plasma proteins that enhance immune responses and facilitate pathogen elimination, acting as a crucial component of innate immunity.

3. What is the primary purpose of complement effector functions in the immune response?

A. To produce cytokines for immune cell communication

B. To generate antibodies against pathogens

C. To inhibit inflammation and prevent tissue damage

D. To promote pathogen elimination through lysis, opsonization, and inflammation

Answer: (D)

Обяснение

Complement effector functions are aimed at eliminating pathogens by lysing microbial cells via MAC, tagging them for phagocytosis through C3b opsonization, and recruiting immune cells with C5a. These mechanisms work together to effectively clear infections, which is the primary role of these functions.

4. Who is credited with proposing the role of the classical pathway of the complement system in linking innate and adaptive immunity?

A. Jules Bordet

B. Elie Metchnikoff

C. César Milstein

D. Louis Pasteur

Answer: (A)

Обяснение

The classical pathway of the complement system is recognized for its role in linking innate and adaptive immunity, primarily through its activation by antigen-antibody complexes. Among the options, Jules Bordet is known for his work on immune mechanisms, including complement research, and is credited with foundational discoveries in immunology related to complement activation and its role in immune responses.

5. What specific trigger initiates the classical pathway of complement activation?

A. Direct recognition of microbial surfaces by complement proteins

B. Spontaneous hydrolysis of C3 in the plasma

C. Formation of immune complexes with antibodies

D. Binding of mannose-binding lectin to pathogen surfaces

Answer: (C)

Обяснение

The classical pathway is initiated specifically by the formation of immune complexes with antibodies, which is explicitly stated in the source content. This distinguishes it from the lectin pathway, which is triggered by mannose-binding lectin, and the alternative pathway, which is triggered by spontaneous hydrolysis of C3 or direct recognition of microbial surfaces. Therefore, the correct trigger for the classical pathway is the formation of immune complexes with antibodies.