Targeted Interleukin-10 Gene Therapy in
Sepsis Syndromes
(R01-GM63041)
The treatment of the hospitalized patient with sepsis remains a
clinical conundrum, due in large part to the complexity of the host
response to infection and tissue injury. Pro- and antiinflammatory
cytokines play critical roles in the development of sepsis syndromes,
but their production is often localized to individual tissues, rather
than the systemic circulation. Current therapeutic approaches for the
treatment of sepsis syndromes involve the systemic administration of
biological response modifiers, such as cytokine antagonists or
antiinflammatory agents. To date, none of these agents has proven
effective, and one explanation may be that their systemic
administration is an inefficient or even inappropriate means to treat
a more localized inflammatory or immunosuppressive response.
We have proposed that the targeted delivery of protein-based therapies
using a recombinant adenoviral vector can directly modulate the
inflammatory or apoptotic processes occurring in the target tissue,
without systemic immune suppression or activation. Therefore, the
overall objective of these studies is to determine the feasibility of
adenovirus gene transfer as a therapeutic modality. More specifically,
the goals of this proposal are to determine whether the forced
overexpression of initially IL-10, but also in later years, a dominant
negative I-kB super-repressor, will blunt the sepsis responses in
target organs without producing systemic immune suppression.
The two specific aims of the current application are: 1) To determine
whether targeted expression of IL-10 in the lungs of mice with an
adenoviral vector can prevent the development of respiratory distress
syndrome in a zymosan-induced model of multisystem organ failure,
without increased expression in other organs or the induction of
T-cell hyporesponsiveness and immune suppression, and 2)
To determine the mechanisms by which targeted expression of IL-10 in
the thymus of mice can reduce caspase-3 dependent thymocyte apoptosis
and improve outcome in a cecal ligation and puncture model of a
compensatory antiinflammatory response syndrome. The studies proposed
in this application will ultimately determine the utility and safety
of adenovirus based gene therapy as a means of targeting protein-based
therapies to individual tissues and organs in sepsis syndromes.
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