18. 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?

Gap-fill exercise

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The antibodies of the immune
system act against agents,
like toxins or , but they are not
in the intracellular space they
cannot fight virus .

In case of viral (and also of
cancerous precancerous cells) the
immune is made by the
immune system, mediated by and NK
(natural killers) that
destroy specific cells virus.