Live attenuated Leishmania major p27 gene knockout as a novel vaccine candidate: A study on safety, protective immunity and efficacy against canine leishmaniasis caused by Leishmania infantum.

Canine leishmaniasis (CanL) is an important parasitic e disease caused by Leishmania infantum and is transmitted by female phlebotomine sand flies primarily between canines and secondarily to humans. Recently, we showed that immunization with Leishmania major p27 gene knockout (Lmp27-/-) as a live attenuated vaccine was safe, induced immunogenicity, and protected against the development cutaneous and visceral leishmaniasis in mice. The p27 protein is a component of the COX protein complex which is responsible for ATP production. In this study, we analyzed the Lmp27-/- candidate vaccine potential with this regard to the safety and induction of immunogenicity and protection against CanL. Variables such a clinical manifestation, anti-Leishmania antibodies using direct agglutination test (DAT), lymphocyte proliferation, delayed-type hypersensitivity (DTH), bone marrow aspiration (BMA) and parasite burden using parasitological and molecular examinations were measured. The results demonstrated that the Lmp27-/- vaccinated group showed no clinical signs after inoculation with Lmp27-/- mutant during a 12-month follow-up, and had significantly higher T-cell responses (Lymphocyte proliferation and DTH), lower seroconversion and parasite burdens following a challenge inoculation with L. infantum after 6-mounth. In conclusion, vaccination with Lmp27-/- parasites would be safe and provide significant immunoprotectivity and efficacy against infection with wild type (WT) L. infantum.

Pediatric hydatidosis in Iranian referral pediatrics center.

BACKGROUND: Hydatidosis is one of the major zoonotic diseases that cause considerable public health problems in Iran. The present study was designed to investigate pediatric hydatidosis in patients referred to the Children Medical Center Hospital in Tehran, Iran during 2005-2010. METHODS: Data were collected from the records of 17 patients referred to the center with hydatidosis. Data included demographic data; laboratory results, type, and site of cysts, clinical manifestations, and treatment. RESULTS: Nine patients were boys (52.9%) and eight (47.1%) were girls. Most patients referred from central areas of Iran (58.8%). Seven patients had cysts in their lungs (41.2%) and three cases (17.6%) in liver. Six cases (35.3%) had simultaneous lung and liver cysts, 3 patients (17.6%) had brain cysts (alone or in combination with other organs involvement) and 2 patients (11.7%) showed multi-organ involvement. All patients were treated by albendazole and underwent surgery, recurrence was seen in 4 (23.5%) of the cases and one patient died due to rupture of the cyst and anaphylactic shock. CONCLUSION: Multi-organ involvement seems to be on the rise in children, this has led to the necessity for physicians to be more aware of clinical features, search, and rule out other organs for involvement diagnosis once a cyst is detected in one organ.