Why IP route is more protective than Subcu ? - (Jan/03/2007 )

Hi

I am trying to investigate how far my vaccine( protein from a Gram negative bacteria )can protect the BALB/C mice from LD50 challenge.

I found the mouse injected intraperitonealy have shown better immunity than the mouse injected subcutaneously.

Why it is not giving the same protection? It that to do with the pathogen infection mood?

Anyone can give me some suggestion?

Thank you so much!

There could be alot of reasons for this. How do you infect the mice with the Gram negative bacteria? How many times do you give the vaccine befoe challenging the mice and do you use an adjuvant?

This is pure speculation but one possible explanation may be access to antigen present cells. The peritoneal cavity contains high numbers of resident professional antigen presenting cells (APC) such as macrophages and dendritic cells. Sub-cut. may be less efficient as the vaccine will encounter less APC. Maybe using higher amounts of protein to vaccinate sub cut or trying a few booster injections will give you better results sub-cutaneously. Again I'm speculating here.