Hi,

Please put more details on your work. Which vaccine?? and vaccine development ??or new adjuvant development????

Regards

Vaccines are usually administered sub cut or IM with mice though other routes are possible (eg inhaled).  Bare in mind that some adjuvants cause formation of granulomas so it is inadvisable to inject into the muscle (for example Complete Freunds Adjuvant) where it could restrict movement and cause pain.

Are you going to be injecting with an antigen or just the adjuvant alone?

First of all, you need to select an antigen that ideally should be a poor immunogen so that you may see the adjuvant effect clearly. Secondly, you have to find the antigen or disease target against which you will be developing vaccine and the type of protective response desired - humoral or cell mediated immune response. That will affect the selection of adjuvant. Then you choose your animal model. As most of the licensed vaccines work through generation of functional antibodies (humoral response) against the pathogen or virulence factors, such as toxins, you may be looking for an immunogenicity type animal model. You may select mice or guinea pigs and route of injection should be close to the route of injection for the potential vaccine in humans. Subcutaneous or Intramuscular injections are common in animal models as most of the vaccines in humans are given intramuscularly. For evaluating an adjuvant effect, the immunization schedule should involve only one injection as 2 injections of antigen without adjuvant usually give very high antibodies. Attached article may provide you some references and more information on the selection of animal models for evaluating vaccine adjuvants.

Dear, Giulia the answer would be depend. However I will try to help you to find the right route to your experiment.

When we are administering a drug, usually we want it to be available in the highest concentration in the shortest time possible, usually! But with a vaccine administration it is the other way around. We want the antigen to be in contact with the immune system as long as possible. So, we try to use routes less vascularized, like the subcutaneous (SC), this slower perfusion of the vaccine thought the tissue. But the route the intradermal injection (ID) route could be used also. This route is more difficult to use, mainly when the animal skin is very thin like a mouse. So, it is going to need an experienced professional to administer the vaccine. But I remember read an article where ID route, have the best immune response, compared to SC and IM (Intramuscular). Intramuscular is a common route used in vaccines for people, like Influenza, yellow fever and others. The muscle is a well irrigate tissue.

The ideal route depends on the type of vaccine and intended effect. For example, mucosal routes such as nose and lungs work quite well for influenza and do generate mucosal antibodies required for the neutralization of virus. Although routes such as I.m. do work, but the scarcity of antigen presenting cells at deltoid muscle makes it a less favorable route. More info on the type of vaccine would help in choosing the right route.