L7

Question 1

Antibodies

Answer 1

Contribute to immune responses via neutralization, opsonization, agglutination, complement activation, ADCC, and degranulation

Question 2

IgM

Answer 2

First antibody isotype produced, efficient in complement activation and agglutination

Question 3

IgG

Answer 3

Functions in opsonization, complement activation, neutralization, and mediates ADCC

Question 4

IgA

Answer 4

Provides mucosal immunity by neutralizing pathogens in secretions

Question 5

IgE

Answer 5

Involved in allergic reactions and defense against parasites through degranulation

Question 6

IgD

Answer 6

Found on mature B cells and aids in activating basophils and mast cells

Question 7

Fc receptor

Answer 7

Protein on immune cells binding the Fc region of antibodies to mediate effector functions

Question 8

Macrophages and neutrophils

Answer 8

Express Fc_ receptors for antibody-mediated phagocytosis

Question 9

NK cells

Answer 9

Express Fc_RIII for antibody-dependent cell-mediated cytotoxicity (ADCC)

Question 10

Mast cells and eosinophils

Answer 10

Express Fc_RI for degranulation in allergic and parasitic responses

Question 11

Complement activation by IgM

Answer 11

More efficient than IgG due to pentameric structure binding multiple C1q molecules

Question 12

Agglutination

Answer 12

Process where antibodies (e.g., IgM, IgA) cause pathogens to clump, enhancing clearance

Question 13

Viral neutralization

Answer 13

Antibodies bind viral surface proteins, preventing entry into host cells

Question 14

Antibody-dependent cell-mediated cytotoxicity (ADCC)

Answer 14

Antibodies tag cells for killing by NK cells or other immune cells

Question 15

Cross-presentation

Answer 15

APCs present extracellular antigens on MHC class I to activate cytotoxic T cells

Question 16

Cytotoxic T lymphocytes (CTLs)

Answer 16

Kill infected or tumor cells via perforin/granzyme pathways or Fas/FasL interaction

Question 17

Natural Killer (NK) cells

Answer 17

Target cells lacking MHC class I, killing them via cytotoxic granules

Question 18

Natural Killer T (NKT) cells

Answer 18

Hybrid cells contributing to immune regulation and cytotoxic responses

Question 19

Perforin

Answer 19

Protein forming pores in target cell membranes to allow entry of granzymes

Question 20

Granzyme

Answer 20

Protease inducing apoptosis in target cells via activation of caspases

Question 21

Caspase-3

Answer 21

Executioner caspase activated during apoptosis in target cells by CTLs or NK cells