Question

1. Two students are studying for an exam on the body’s defensive systems. One of them insists that complement is part of the non-specific second line defense, but the partner insists that complement is part of a humoral immune response in the third line of defense. How would you explain to them that they are both correct?

2. In general, what sorts of pathogens would successfully attack a patient with an inability to synthesize B lymphocytes?

3. Plasma cells are vital for protection against infection, but memory B cells are not. Why not?

4. What sorts of pathogens could successfully attack a patient with an inability to produce T lymphocytes?

5. Do you think "All diseases begin in gut" as reported by Hippocrates?

Answer 1

1. Both are correct because complement system works in both the ways. Several complement factors provides non-specific innate immunity by acting against common bacterial antigens. Complement system promotes inflammation to helps fight the common pathogens.

In addition, other complement factors also contribute to humoral immunity by interacting with antigen-antibody complexes and enhances the ability of antibodies to clear the microbes or damaged cells.

2. Pathogens such as extracellular microbes are best fought by immune system vua antibody responses. Immune system identifies by binding with antigens present on microbes. Hence, foreign bacteria would successfully attack a patient with an inability to synthesize B lymphocytes.

3. Memory cells do not participate directly into the current infections. However they helps in identification of previously encountered pathogens. Plasma cells produces amtibodies that fight the infections.

4. All sorts of pathogens could successfully attack a patient with an inability to produce T lymphocytes because helper T cells would not be able to coordinate humoral as cell as cell-mediated immunity.