2. Learning Objectives
• Understand the mechanism used by
the immune system to fight with:-
Extracellular bacteria
Intracellular bacteria
Viruses
3. General features of Immune
response to microbes
Responses always involve innate and adaptive
immunity.
The immune system responds in distinct and
specialized ways to different type of microbes
to be most effective.
Microbes evade or resist the effector
mechanism of immunity.
Many microbes establish latent, or persistent
infections-immune response controls but does
not eliminate the microbe and the microbe
survives without propagating the infection.
5. Immunity to Extracellular
bacteria
Innate:
Complement activation.
Activation of phagocytes.
Inflammatory response.
Adaptive:
Humoral immunity:-
Antibodies block infection
Eliminate microbes
Neutralize toxins
Activation of CD4+
TH cells:-
Enhance phagocytic and microbicidal
activities of macrophages and neutrophils.
Stimulate Antibodies production.
6.
7.
8. Immunity to Intracellular
bacteria
Innate:
Activation of phagocytes.
Activation of NK cells.
Adaptive:
Activation of CD4+
TH lymphocytes.
Activation of CD8+
TC lymphocytes.
9.
10.
11.
12. Immunity to Viruses
Innate:
Activation of Complement system.
Activation of NK cells.
Production of Type 1 Interferons(IFN)
Adaptive:
Humoral Immunity.
Activation of CD8+
TC lymphocytes (Kill
virus infected cells).
13.
14.
15.
16. Latest Research
• CDC Grows SARS-CoV-2, the virus
that causes COVID-19, in Cell
Culture.
• A Systematic Review on the Efficacy
and Safety of Chloroquine for the
Treatment of COVID-19.
• The Trial of Chloroquine in the
Treatment of Corona Virus Disease
2019 (COVID-19) and Its
Research Progress in Forensic
Toxicology
17. MCQs
Q1.Which of the following substances
will not stimulate an immune
response unless they are bound to a
larger molecule?
a. Antigen
b. Virus
c. Hapten
d. Miligen
e. Antibody
A.Hapten is a small molecule; they can
act as antigen if it binds to a larger
protein molecule. So the answer
is “c”
18. Q2. Which of the following immune
cells/molecules are most effective at
destroying intracellular pathogens?
a. T helper cells
b. B cells
c. Antibodies
d. Complement
e. T cytolytic cells
A. cytolytic cell Tc cells and Natural
killer cells kill infected host cells
which are harboring intracellular
pathogen. So answer is option “e”