Prior Toxin Sensitization Modulates Response to RSV Infection

[Guest guest]

Also evidence that the administration of Pertussis vaccine may lead

to increase in RSV problems

http://www.medscape.com/reuters/prof/2000/10/10.09/20001006scie005.html

Prior Toxin Sensitization Modulates Response to RSV Infection

Reuters Medical News

WESTPORT, CT (Reuters Health) Oct 9 - In animal experiments, priming with

pertussis toxin alters the pathogenicity of subsequent respiratory

syncytial virus

(RSV) infection, according to researchers from Vanderbilt University,

Nashville,

Tennessee.

Dr. Barney S. Graham and colleagues treated BALB/c mice with pertussis toxin

(PT) parenterally before challenge with RVS. " Priming with purified and

detoxified

PT before RVS challenge increased postchallenge weight loss and mortality, "

according to their report in the October issue of the Journal of Infectious

Diseases.

Further, Dr. Graham's group found that " PT priming changed the kinetics,

location

and composition of the cellular infiltrate in the lung but altered neither

antibody

responses nor virus titers. "

In addition, they report that " priming with purified, but not genetically

detoxified, PT

propagated a modest type 2 cytokine response to RSV antigens. " They also found

that " anti-interlukin-4 treatment before RSV challenge failed to abrogate

the effects

of PT priming. "

" The preexisting immune environment, " Dr. Graham and colleagues conclude, " can

change virus-specific immunity. They add, " the ability of bacterial

antigens to alter

the immune response to live virus has implications that should be

considered in the

rational design of vaccines and immunization schedules, as well as in the

analysis of

the pathogenesis of natural infections. "

J Infect Dis 2000;182:1029-1038.