Leishmania parasites are able to survive in host macrophages despite the harsh phagolysosomal vacuoles conditions. This could reflect, in part, their capacity to secrete proteins that may play an essential role in the establishment of infection and serve as targets for cellular immune responses. To characterize Leishmania major proteins excreted/secreted early after promastigote entry into the host macrophage, we have generated antibodies against culture supernatants of stationary-phase promastigotes collected 6 h after incubation in conditions that partially reproduce those prevailing in the parasitophorous vacuole. The screening of an L. major cDNA library with these antibodies led us to isolate 33 different cDNA clones that we report here. Sequence analysis revealed that the corresponding proteins could be classified in 3 groups: 9 proteins have been previously described as excreted/secreted in Leishmania and/or other species; 11 correspond to known proteins already characterized in Leishmania and/or other species although it is unknown whether they are excreted/secreted and 13 code for unknown proteins. Interestingly, the latter are transcribed as shown by RT-PCR and some of them are stage regulated. The L. major excreted/secreted proteins may constitute putative virulence factors, vaccine candidates and/or new drug targets.

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The aim of this study is to estimate the prevalence of Toxoplasma gondii infection in 527 sheep from 4 governorates of Tunisia by Elisa (350 animals) and PCR (177 animals). The seroprevalence in sheep was estimated to be 1.8% (N = 166) in the governorate of Siliana (North Tunisia) and 19% (N = 184) in the governorate of Kasserine (Central Tunisia) with a commercial Elisa kit. T. gondii DNA was extracted from the apex of the heart in 25.5% (N = 106) of sheep from the Sidi-Bouzid governorate (Central Tunisia) and 12.7% (N = 71) from the Ben-Arous governorate (North Tunisia). There was no statistically significant difference between different age categories' prevalence within each locality. Our results indicate that T. gondii infection is frequent in Tunisian sheep. The implementation of a national control programme against toxoplasmosis should not neglect sheep as a frequently infected intermediate host.

Background Ocular manifestations in dogs with leishmaniasis are frequent and complications in affected tissues can lead to blindness. Immune processes play a very important role in the pathogenesis of ocular inflammation. Therefore, the immunology of ocular manifestations in dogs with leishmaniasis remains complex and poorly understood. Objectives Estimation and characterisation of ocular and periocular manifestations in dogs naturally infected with Leishmania infantum and investigation of the production site of specific anti‐Leishmania infantum IgG. Methods The present investigation used 53 confirmed dogs infected with Leishmania infantum, presenting ocular and periocular lesions, and 10 control non‐infected dogs. Complete macroscopic ophthalmic examination of eyelids and globes was performed. Both total and anti‐Leishmania infantum IgG antibodies were studied in sera and aqueous humour (AH) of all dogs by ELISA technique. A Goldmann–Witmer coefficient (C value) was calculated. Results The main ophthalmological findings were keratoconjunctivitis (71.7%; 38/53), hyperplasia of conjunctival lymphoid follicles (54.7%; 29/53), blepharitis (50.9%; 27/53) and uveitis (20.7%; 11/53). Ocular production of anti‐Leishmania infantum IgG was detected in 73.6% (39/53) of infected dogs. There was no correlation between the antibody levels in AH and sera of the same dog. The mean anti‐Leishmania infantum IgG in AH was higher in uveitis, followed by lesions affecting only the adnexa (p < 0.0001). The highest mean C values were observed for uveitis, conjunctivitis and keratitis. Conclusions Our findings suggest that production of anti‐Leishmania IgG in dogs infected with Leishmania infantum with ocular manifestations begin in situ and follows by a transfer of antibodies from the bloodstream to the AH.

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BackgroundVisceral leishmaniasis is a zoonotic disease of major public health concern in several countries in the world. The local population awareness would improve prevention, early detection and treatment of both human and animal leishmaniasis.MethodsThe aim of this survey was to assess the knowledge about visceral leishmaniasis in a sample of dog owners visiting the National School of Veterinary Medicine of Sidi Thabet, Tunisia, through a structured questionnaire.FindingsTwo hundred dog owners were interviewed, 87% were men and 47% had higher education level. Ninety four per cent were from neighbouring districts to Ariana, where the National School of Sidi Thabet is located. Out of 200 respondents, 79 confirmed knowing leishmaniasis. The correct answers concerning canine visceral leishmaniasis (CVL) (77%) were significantly higher than those concerning human visceral leishmaniasis (HVL) (23%). Correct answers concerning CVL were given in part by previously diseased dogs' owners. The respondent could not explain what is exactly leishmaniasis, but the majority of questioned persons know that human and dogs are the most important hosts. Forty-four out 79 (56%) of the persons think that mosquitoes or insects are the vectors of leishmaniasis and 63% (53/79) knows that it is a zoonotic disease but 72% (38/53) were not able to define how.ConclusionDespite the frequent visits to veterinarians for vaccination or other medical issues and their long experience in dog breeding, the sample of dog owners had not enough knowledge and several misconceptions regarding leishmaniasis. Large education programmes should be implemented in Tunisia to improve the knowledge of the Tunisian population, especially dog owners, concerning leishmaniasis.

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