IMMUNOLOGY NOTES | @sciencera.learntothink
IMMUNOLOGY NOTES
BMI2607 – UNISA
TOPICS COVERED:
1. CELLS OF IMMUNE SYSTEM
2. IMMUNE RESPONSE
3. MAJOR HISTOCOMPATIBILITY
COMPLEX
, IMMUNOLOGY NOTES | @sciencera.learntothink
Table of Content:
1. Primary Immune Response
2. Lag phase
3. Exponential Phase
4. Plateau Phase
5. Decline phase 2
6. Secondary Immune Response
7. Thymus-Dependent and Thymus-Independent Antigens Vs Immune Responses
8. Factors that Influence the Type of Immune responses
9. Primary Immune Response vs Secondary Immune response
10.Major Histocompatibility Complex (MHC) Molecules Characteristics
11.HLA complex
12.Gene Products of HLA complex
13.Major Histocompatibility Complex (MHC) Types
a. Class I MHC Molecule
b. Class II MHC Molecule
c. Class III MHC Molecule 9
14.Distribution of MHC
15.Importance of MHC
16.Antigen Presentation and Processing
17.Antigen Presentation Pathway: Class I MHC molecules (Cytosolic pathway)
18.Antigen Presentation Pathway: Class II MHC molecules (Endocytic Pathway)
19.Clinical Significance of Antigen Presentation and Processing
20.List of Cells of Immune System
21.Lymphoid cells (Lymphocytes)
1. B-lymphocytes
2. T-Lymphocytes
3. Natural killer cells (NK cells)
22.Mononuclear Phagocytes
23.Granulocytic Cells 17
24.Neutrophils
25.Eosinophils
26.Basophils
27.Mast Cells
28.Dendritic Cells
, IMMUNOLOGY NOTES | @sciencera.learntothink
IMMUNOLOGY NOTES
Immunology is a rapidly growing field of medicine that investigates several
elements of the immune system, including cells, structure, function, antigen
response, and diseases.
• The immune system is made up of cells, chemicals, processes, and systems
that work together to protect the body from external antigens such as
bacteria, fungi, and parasites, as well as viruses, cancer cells, and poisons.
• The immune system has two lines of defense: innate immunity and adaptive
immunity. In addition to the structural and chemical barriers that protect us
from infection, the immune system has two lines of defense: innate immunity
and adaptive immunity.
• Innate immunity is the host's initial line of defense against antigens, and it's
an antigen-independent defense system that kicks in instantly or within hours
of an antigen contact.
• Adaptive immunity, on the other hand, is antigen-dependent and antigen-
specific, with a lag time between antigen exposure and maximal response.
• Immunology research focuses on determining the physiological functioning
of the immune system in both healthy and diseased states, as well as the
system's malfunctioning in the event of illnesses and the physical, chemical,
and physiological features of immune system cells.
• Immunology is rapidly growing in importance in clinical medicine due to its
intimate ties to organ transplantation, cancer, virology, bacteriology, and
even dermatology.
• Immunology is concerned with organs such as the bone marrow and
lymphatic system, as well as white blood cells in the blood.
• These cells, or the organs that produce them, are directly or indirectly
responsible for the body's defense system against a pathogenic agent or
other antigens.
• These cells circulate throughout the body via blood or lymph to identify
antigens that enter the body from a variety of sources.
• Immunotherapy, in which components of the immune system or antigens are
employed to treat a disease or problem, is an essential area of immunology.
, IMMUNOLOGY NOTES | @sciencera.learntothink
IMMUNE RESPONSE
Immune Response is a mechanism of how the immune system of the
host’s body responds to a harmful foreign particle or pathogen (antigen) in
the body.
• It requires detecting antigens and triggering defense mechanisms against
invading invaders. Immune responses are elicited in order to guard against
antigens, which are chemicals found on the surfaces of cells, viruses,
bacteria, and fungi. In nature, antigens are proteins; however, antigens can
also be medications, poisons, toxins, and foreign particles like splinters.
• Bacteria, viruses, fungi, and parasites are examples of pathogens that cause
an immune response. As a result, the immune system plays a critical role in
identifying and killing (or attempting to destroy) antigen-containing
compounds.
• The immune system responds in two ways:
o Immune Response (Primary)
o Response of the Secondary Immune System
Primary Immune Response
• When the immune system of the body encounters an antigen for the first
time, it is called a primary immunological reaction.
• The body learns to recognize the antigen, produces antibodies against it,
and induces a long-term memory reaction against it during this
immunological response.
• The development of immunological memory lymphocytes facilitates memory
induction.
• The activation of naive B-cells and naive T-cells was part of the reaction
elicited.
• The resolution of the response takes roughly 14 days.
• When the body reacts to an antigen for the first time, it goes through four
steps of immunological response. This is because the primary reaction
induced by the immune system when it detects an antigen for the first time
is brief and mild, and it occurs in these phases: lag, exponential, plateau,
and decline.
