Immune System: A Report on Three Lines of Defense Mechanisms

This report examines the human immune system's three primary lines of defense against pathogens. The first line, including skin and mucous membranes, acts as a physical barrier. The second line involves nonspecific cellular responses, such as phagocytes, which engulf foreign bodies. The third line of defense, the adaptive immune response, involves lymphocytes that produce antibodies specific to antigenic fragments, providing long-term immunity. References from Engelkirk, Duben-Engelkirk & Burton (2011) and Cardamone et al. (2016) support the discussion of these mechanisms, detailing how the immune system combats infections and maintains bodily health.

Running head: IMMUNITY
IMMUNITY
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Three line defence mechanism of the health to combat pathogen:
The immune system works as a network of cells and tissues for protecting the body.
Attacking viruses and bacteria try to invade the body where immune system targeted them while
leaving healthy tissue alone. In this context, the body uses three lines of defences against
pathogenic infection. The first line of defence against infection is skin, mucous membrane and
physical barriers which can prevent the entry of the pathogen (Engelkirk, Duben-Engelkirk &
Burton, 2011). The second line of defence is nonspecific phagocytes and other internal
mechanisms that comprises innate immunity. The third line of defences that can produce
antibodies as a part of adaptive immunity.
The first line of defence:
It is the chief defence against infections and these surfaces include skin where dryness,
acidity and temperature inhibit the growth of the pathogen (Engelkirk, Duben-Engelkirk &
Burton, 2011).. Both skin and mucous membrane release chemicals that can restrict the
multiplication of microbes. A prominent example is acidity and temperature of skin that can
prevent entry.
The second line of defence:
The second line of defence is against impurity are nonspecific cellular as well as a
molecular response which do not differentiate pathogens types and response in similar ways.
One of the prominent examples is phagocytic leucocytes that migrate to the infection site and
engulf the foreign bodies or antigen that were detected (Cardamone et al., 2016). This response
can induce swelling amongst individuals.

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The third line of defence:
The final line of defence is the lymphocytes which produce antibiotics to specific
antigenic fragments. One of the prominent examples of the third line of defence is an antibody
for a specific fragment. After the identification of antigens, B cells produce specific antibodies in
response to the T cell and antibodies recruited in the area to diminish the antigen and provide
long term immunity (Cardamone et al., 2016).

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References:
Cardamone, C., Parente, R., De Feo, G., & Triggiani, M. (2016). Mast cells as effector cells of
innate immunity and regulators of adaptive immunity. Immunology letters, 178, 10-14.
Engelkirk, P. G., Duben-Engelkirk, J. L., & Burton, G. R. W. (2011). Burton's microbiology for
the health sciences. Lippincott Williams & Wilkins.