Immunology Quiz: Cell-Mediated and Humoral Immunity

Cell-Mediated Immunity

• T lymphocytes (T cells) play a critical role in cell-mediated immunity.
• It involves direct attack on infected or abnormal cells, primarily by cytotoxic T cells.

Humoral Immunity

• Secreted antibodies primarily function to neutralize pathogens and toxins.
• They can opsonize pathogens, marking them for destruction by other immune cells.

Elimination of Infection Reservoirs

• Cell-mediated immunity eliminates reservoirs of infection by activating T cells to destroy infected host cells.
• This response restricts the spread of pathogens within the host.

Immunological Memory

• The immune system's memory allows it to mount larger and more effective responses upon subsequent exposures to the same antigen.
• This is primarily facilitated by memory T and B cells.

Self vs. Non-Self Discrimination

• The property of distinguishing between self and non-self antigens is known as tolerance.
• This ensures that the immune system does not attack the body’s own tissues.

Activation of Macrophages

• CD4+ T cells, also known as helper T cells, are key in activating macrophages to enhance their ability to kill phagocytosed microbes.
• They secrete cytokines that boost the functionality of macrophages.

Antibody Form in Humoral Response

• Antibodies are typically found in a soluble form in bodily fluids, such as blood and lymphatic fluid.
• They are produced by B cells in response to specific antigens.

Recognition of Diverse Antigens

• The immune system can recognize billions of different antigens due to the diverse repertoire of B and T cell receptors generated through random genetic recombination.
• This diversity is essential for effective immune responses against various pathogens.

Antibody-Mediated Immunity

• Humoral immunity is characterized by the use of secreted antibodies to block infections by neutralizing pathogens or preventing their entry into host cells.
• It includes mechanisms like agglutination and activation of the complement system.

Reactivity Against Microbes

• The acquired immune response has the ability to react against a vast array of microbes while avoiding reaction to the host's own antigens, a property known as specificity.
• This balance is crucial for preventing autoimmune disorders.

Test your knowledge of the immune system, including cell-mediated and humoral immunity, and the characteristics of the acquired immune response.