Biology Questions and Answers
entire life of the individual, and they
become the memimmune system. When the body isory cells of the (^)
exposed in the future to the same
antigen be faster anthe production d more intense of antibodies willsince the
immune system is already prepared to
react against that antigen. This is calledthe secondary response.
- How can the immune
memory lead to the efficacy of
vaccines and also produce
allergies?
Vaccines arfragments of infectiouse controlled inoculations agents or of of
inactive infectious agents to induce the
primary immuformation of specific memory ne response, theB (^)
lymphocytes against the antigen.
Therefore the organism producesimmunoglobulins and becomes prepared (^)
to destroy antigens when exposed to
new infections by those agents.
In allergies the humoral immunis sensitized (makes antibodies ane systemd
specific memory B lymphocytes) against
some commosubstances wrongly recon environmgnized asental (^)
antigens. For example, pollen-derived
substances,present in foods or in medicines, etc. dust particles, compounds
may be recognized as antigens
triggering the primary rcreating an immune memory aesponse andgainst (^)
them that then become causes of
allergy. The more the individual isexposed to those substances the more (^)
intense is the immune reaction.
The IgE antibodies that cause bind to receptors of leukocytes calledallergy (^)
mastocytes whose cytoplasm is full of
histamine mastocytegranules. T bond causes thhe antibody-ese cells to
release a great amount of histamine in
the circulation, stimulating inand generating the allergic symptomsflammation
and signs. For this reason allergy is
treated with block the histaminicantihistamines, reaction. drugs that
Exacerbated allergic reactions, for
example, medicines likin hypersensitivitye penicillin and sulfas, may to some (^)
cause anaphylactic shock, a severe
clinicalto death. condition that sometimes leads
- How different are the
actions of antibodies against
bacteria and against virus?
Why is the cellular immune
response activated in case of
chronic viral infection?
The antibodies of the humoral immune
system actlike toxins or bacteria, against extracellular a but they are notgents,
active in the intracellular space and they
cannot fight virus efficiently.
In case of viral infection (and also of
cancerimmune attack is made by the cellularous or precancerous cells) the (^)
immune system,(natural killers) lymp mediated by T and NKhocytes that
destroy specific cells and virus.
- How does the cellular
immune response take place?
The lymphocytes that participate in the
cellular immune response are the T
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