Ruth Foxwell writes:
> I have recently conducted a number of depletion studies in mice using rat
> anti mouse monooclonal antibodies. The mice I was depleting of various
> cells and cytokines, had been previously immunised against a bacterial
> infection. The depleted immunised mice were challenged with bacteria.
> Measurement of IgG specific to the bacteria in the serum post challenge of
> the mice was found to be adversly effected in the cell or cytokine depleted
> mice compared with those immunised but not depleted. IgA levels showed a
> slght adverse effect but not nearly as noticeable as the IgG levels. Has
> anyone done similar studies or have any theories to throw light on why
> depleted animals are not showing similar serum antibody levels as the non
> depleted animals?
>> I look forward to your thoughts - Ruth
Ruth:
I am a bit confused. Wouldn't you expect that cell or cytokine depleted
animals ought to respond less vigorously to bacterial challenge than the
non-treated animals? After all, it presumably is the cytokines (and
their cell sources) that orchestrate the response to antigenic
re-challenge. Without knowing what specific depletions you used (and
the relative success of those depletions) its hard to say why IgA
responses might have been less impacted than IgG -- but there certainly
could be reasons depending on which cytokines were affected (I would
expect depleting IL-4 to have this effect, for example). Similar
studies are rampant in the literature -- this is how the activities of
many cytokines were intially elucidated. These days, the depletions are
often accomplished genetically -- using "knockout" mice.
Cheers -- Dom Spinella