( als are thus a reservoir for these para...)Visceral Leishmaniasis: Successful Vaccine Trial In Dogs

als are thus a reservoir for these parasites, which continuously feed the mammal-sand fly-human cycle. In this context, development of a canine vaccine would help reduce the portion of the animal population infected. The risks of transmission of the disease to humans would in this way be indirectly reduced.

Up to now, several dog vaccines, mostly developed from whole dried parasites, have proved not to be really effective. A team from the IRD Montpellier research centre, working with the Rocher veterinary clinic (La Garde, Var, France) and the biopharmaceutical firm Bio Véto Test (La Seyne-Sur-Mer, Var), have recently produced and tested a new type of treatment, composed solely of antigen proteins excreted by the parasite (1). The first trials indicate that this would completely and lastingly protect dogs against the disease.

Twelve out of 18 dogs included in the study were treated with increasing doses of protein antigens excreted by the parasite (that is 50, 100, 200 micrograms) made up to a formula with an adjuvant. The other six received no treatment. Two injections at an interval of three weeks resulted in infection of all the animals with L. infantum. They were followed up for two years in order to monitor the progress of the disease. The mixture of parasite proteins proved to be especially effective, as 100% protection was obtained for the doses of 100 micrograms (six immunized dogs out of six) and 200 micrograms (three out of three).

The researchers also focused on the changes to the immune system brought on by the vaccination. Laboratory experiments showed that the effectiveness of the vaccine stems from the activation of certain cells of the immune system, the T lymphocytes of type Th1. These induce the infected macrophages to produce nitric oxide, highly toxic for cells. This process, which did not occur in the untreated dogs, thus enables macrophages to get rid of the parasites that are infecting them. The animal thus acquires lon
'"/>

Source:Institut de Recherche Pour le D茅veloppement

Page: 1 2 3 4
Related biology news :

1. Successful Test Of Single Molecule Switch Opens The Door To Biomolecular Electronics
2. Penn Surgeons Use Completely Robotic Surgery to Successfully Treat Prostate Cancer
3. Successful cell engineering may lead to mad cow prevention, say researchers
4. Successful transplantation from pig embryos to mice
5. Successful lung cancer surgery not enough to break nicotine dependence in many smokers
6. FDA Approves Human Hookworm Vaccine for Phase I Safety Trials
7. Live Recombinant Adenovirus Vaccine Technique Explored
8. Gene Vaccine Protects Mice Against Development Of Her2/neu Breast Cancer
9. NIAID Initiates Trial of Experimental Avian Flu Vaccine
10. Study Models Impact Of Anthrax Vaccine
11. New Insights Into HIV Immunity Suggest Alternative Approach to Vaccines