8|P age
Innate (non-specific) immunity and
Adaptative (specific) immunity
• Immunity is the ability of the body to resist infection.
• It is the defence mechanisms against antigens or foreign agents in the body.
Infection is the growth of pathogens (bacteria, virus, fungi, parasite) in
the body.
Antigen is anything that stimulates the immune response. It could be
pathogens, pathogen toxins, abnormal cells or infected cells, tumour
cells, an allergen. It is anything that the body recognises as being for-
eign agents or non-self.
Pathogens or infectious agents are microorganisms that have the po-
tential to cause disease. They include bacteria (bacterium in singular),
viruses, parasites, and fungi.
Microbe is short for microorganism. Microorganism means only visible
using a microscope. Not all microbes are pathogens, some live in the
human body and form commensal microbial flora.
Commensal microbes are beneficial or symbiotic microorganisms
which prevent pathogens from being able to colonise and enter the
body.
Allergen is any substances that induce an allergic reaction.
.
,9|P age
Key attributes of immunity
Immunity is divided into 2 types: non- specific or innate immunity and specific or ad-
aptative immunity
Innate or non-specific immunity Adaptative, acquired or specific im-
munity
Present at birth (innate) Not present at birth, it is learned and re-
quires an exposure to a specific antigen
to develop (acquired).
Acts against a wide variety of antigens The immune response is specific to one
but the reaction is the same regardless particular antigen (specific).
of the cause(non-specific) The immunity response to an antigen
adapts, refines, and strengthens to
several exposures with the same anti-
gen(adaptative).
No immunological memory, the re- Immunological memory which results
sponse to an antigen will be the same from primary immune response against
regardless of the number of exposures a particular antigen, leading to a faster
with the antigen. and more effective response to future
exposures to the same antigen.
Immunocompetency which is the Immunocompetency
ability of immune cells to identify and
bind to antigens.
Tolerance which the ability of immunity Tolerance
cells to recognise marker proteins on
body cell membranes or self-markers
from non-self-cell markers such as can-
cer cells, pathogens.
, 10 | P a g e
Components of non-specific immunity and
specific immunity
Non-specific immunity Specific immunity / Acquired
• Normal anatomy and physiology Can be active or passive
( physical and chemical barriers) Active: the body immunity makes its
• Inflammation own antibodies to the specific antigen
• Phagocytosis (Macrophages, that causes the immunity reaction.
neutrophils, and dendritic cells) • Natural: Infection
• Complement • Artificial: Vaccination
• Interferons (cytokines) Passive: antibodies are given to the
• Natural killer lymphocytes body
• Natural: Transplacental, colos-
trum and breast milk
• Artificial: Injections of immuno-
globulins
Active on passive immunity: When babies are born, they have got
passive immunity that they receive from their mothers which do not last
for very long. As they are exposed to antigens or potential infections in
the environment, babies will start making their own antibodies via active
specific acquired immunity while still passively immune.
Innate (non-specific) immunity and
Adaptative (specific) immunity
• Immunity is the ability of the body to resist infection.
• It is the defence mechanisms against antigens or foreign agents in the body.
Infection is the growth of pathogens (bacteria, virus, fungi, parasite) in
the body.
Antigen is anything that stimulates the immune response. It could be
pathogens, pathogen toxins, abnormal cells or infected cells, tumour
cells, an allergen. It is anything that the body recognises as being for-
eign agents or non-self.
Pathogens or infectious agents are microorganisms that have the po-
tential to cause disease. They include bacteria (bacterium in singular),
viruses, parasites, and fungi.
Microbe is short for microorganism. Microorganism means only visible
using a microscope. Not all microbes are pathogens, some live in the
human body and form commensal microbial flora.
Commensal microbes are beneficial or symbiotic microorganisms
which prevent pathogens from being able to colonise and enter the
body.
Allergen is any substances that induce an allergic reaction.
.
,9|P age
Key attributes of immunity
Immunity is divided into 2 types: non- specific or innate immunity and specific or ad-
aptative immunity
Innate or non-specific immunity Adaptative, acquired or specific im-
munity
Present at birth (innate) Not present at birth, it is learned and re-
quires an exposure to a specific antigen
to develop (acquired).
Acts against a wide variety of antigens The immune response is specific to one
but the reaction is the same regardless particular antigen (specific).
of the cause(non-specific) The immunity response to an antigen
adapts, refines, and strengthens to
several exposures with the same anti-
gen(adaptative).
No immunological memory, the re- Immunological memory which results
sponse to an antigen will be the same from primary immune response against
regardless of the number of exposures a particular antigen, leading to a faster
with the antigen. and more effective response to future
exposures to the same antigen.
Immunocompetency which is the Immunocompetency
ability of immune cells to identify and
bind to antigens.
Tolerance which the ability of immunity Tolerance
cells to recognise marker proteins on
body cell membranes or self-markers
from non-self-cell markers such as can-
cer cells, pathogens.
, 10 | P a g e
Components of non-specific immunity and
specific immunity
Non-specific immunity Specific immunity / Acquired
• Normal anatomy and physiology Can be active or passive
( physical and chemical barriers) Active: the body immunity makes its
• Inflammation own antibodies to the specific antigen
• Phagocytosis (Macrophages, that causes the immunity reaction.
neutrophils, and dendritic cells) • Natural: Infection
• Complement • Artificial: Vaccination
• Interferons (cytokines) Passive: antibodies are given to the
• Natural killer lymphocytes body
• Natural: Transplacental, colos-
trum and breast milk
• Artificial: Injections of immuno-
globulins
Active on passive immunity: When babies are born, they have got
passive immunity that they receive from their mothers which do not last
for very long. As they are exposed to antigens or potential infections in
the environment, babies will start making their own antibodies via active
specific acquired immunity while still passively immune.
