In vitro binding and survival assays of Leishmania parasites to peripherical blood monocytes and monocyte-derived macrophages isolated from dogs naturally and experimentally infected with Leishmania (Leishmania) chagasi

<p>Abstract</p> <p>Background</p> <p>There are a few works considering the characterization of canine monocyte-derived macrophages as well as a standardized procedure for isolation, culture, and infection of these cells with <it>Leishmania</it>. We have performed several modifications in order to improve the canine monocyte-derived macrophage cultures. In addition, we have done a comparative study between monocytes and monocyte-derived macrophages from dogs naturally and experimentally infected with <it>L. chagasi</it>.</p> <p>Results</p> <p>In the presence of exogenous serum, opsonized <it>Leishmania </it>promastigotes binds better to monocytes/macrophages than without serum. Otherwise, this binding occurs due to the strict correlation between the opsonized biologic particles with the third receptor of the complement (CR3-CD11b/CD18). In fact, our assays with CD11b confirmed the importance of this receptor for canine cells and the <it>L. chagasi </it>experimental system. Moreover, monocytes obtained from naturally infected dogs have shown a higher number of monocytes bounded to promastigotes. The experimental results regarding survival have shown that promastigote forms of opsonized <it>L. chagasi </it>were more infective, because we found higher numbers of promastigotes bound to the different cells. As a consequence, after forty-eight hours of binding, higher numbers of amastigotes appeared inside monocyte-macrophages.</p> <p>Conclusion</p> <p>These studies have given support to continue comparative studies involving canine monocytes, monocyte-derived macrophages and peritoneal macrophages. Since we have standardized the canine cell culture, we are looking forward to determining the phenotypic properties of these cells before and after <it>L. chagasi </it>infection using flow cytometry.</p

Complement activation-related pseudoallergy in dogs following intravenous administration of a liposomal formulation of meglumine antimoniate

The increasing use of nanotechnologies in advanced therapies has allowed the observation of specific adverse reactions related to nanostructures. The toxicity of a novel liposome formulation of meglumine antimoniate in dogs with visceral leishmaniasis after single dose has been investigated. Groups of 12 animals received by the intravenous route a single dose of liposomal meglumine antimoniate (group I [GI], 6.5 mg Sb/kg), empty liposomes (GII) or isotonic saline (GIII). Evaluation of hematological and biochemical parameters showed no significant changes 4 days after administration. No undesired effects were registered in the GIII. However, adverse reactions were observed in 67.7% of dogs from both groups that received liposomal formulations. The side effects began moments after bolus administration and disappeared during the first 15 minutes after treatment. Prostation, sialorrhea and defecation were the most frequent clinical signs, registered in 33.3% and 41.6 % of animals from the groups GI and GII, respectively. Tachypnea, mydriasis, miosis, vomiting and cyanosis were also registered in both groups. The adverse reactions observed in this study were attributed to the activation of the complement system by lipid vesicles in a phenomenon known as Complement Activation-Related Pseudoallergy (CARPA). The influence of the physical-chemical characteristics of liposomal formulation in the triggering of CARPA is discussed

In vitro binding and survival assays of parasites to peripherical blood monocytes and monocyte-derived macrophages isolated from dogs naturally and experimentally infected with -6

<p><b>Copyright information:</b></p><p>Taken from "In vitro binding and survival assays of parasites to peripherical blood monocytes and monocyte-derived macrophages isolated from dogs naturally and experimentally infected with "</p><p>http://www.biomedcentral.com/1746-6148/3/11</p><p>BMC Veterinary Research 2007;3():11-11.</p><p>Published online 30 May 2007</p><p>PMCID:PMC1894629.</p><p></p>Average of peritoneal macrophages binding to from experimental infected animals with the presence or absence of C5D serum, after 50 min incubation (2,5 × 10parasites/well). (C) Average of infected peritoneal macrophages binding to from naturally infected animals with the presence or absence of C5D serum after, fourth eight hour incubation (5 × 10parasites/well) (*) p < 0.01

In vitro binding and survival assays of parasites to peripherical blood monocytes and monocyte-derived macrophages isolated from dogs naturally and experimentally infected with -7

<p><b>Copyright information:</b></p><p>Taken from "In vitro binding and survival assays of parasites to peripherical blood monocytes and monocyte-derived macrophages isolated from dogs naturally and experimentally infected with "</p><p>http://www.biomedcentral.com/1746-6148/3/11</p><p>BMC Veterinary Research 2007;3():11-11.</p><p>Published online 30 May 2007</p><p>PMCID:PMC1894629.</p><p></p>(B) Average of monocyte-derived macrophages binding to from experimental infected animals with the presence or absence of C5D serum, after 50 min incubation (5 × 10parasites/well). (C) Average of infected peritoneal macrophages binding to from experimental infected animals with the presence or absence of C5D serum after, fourth eight hour incubation (5 × 10parasites/well) (*) p < 0.01

In vitro binding and survival assays of parasites to peripherical blood monocytes and monocyte-derived macrophages isolated from dogs naturally and experimentally infected with -0

<p><b>Copyright information:</b></p><p>Taken from "In vitro binding and survival assays of parasites to peripherical blood monocytes and monocyte-derived macrophages isolated from dogs naturally and experimentally infected with "</p><p>http://www.biomedcentral.com/1746-6148/3/11</p><p>BMC Veterinary Research 2007;3():11-11.</p><p>Published online 30 May 2007</p><p>PMCID:PMC1894629.</p><p></p>overslips (assay with absence of serum C5D). Giemsa. 1000×

In vitro binding and survival assays of parasites to peripherical blood monocytes and monocyte-derived macrophages isolated from dogs naturally and experimentally infected with -1

<p><b>Copyright information:</b></p><p>Taken from "In vitro binding and survival assays of parasites to peripherical blood monocytes and monocyte-derived macrophages isolated from dogs naturally and experimentally infected with "</p><p>http://www.biomedcentral.com/1746-6148/3/11</p><p>BMC Veterinary Research 2007;3():11-11.</p><p>Published online 30 May 2007</p><p>PMCID:PMC1894629.</p><p></p>e of promastigotes bound to monocytes of animals experimentally infected (AEI) with in the presence or absence of C5D serum (2,5 × 10parasites/well) (*p < 0.01)

In vitro binding and survival assays of parasites to peripherical blood monocytes and monocyte-derived macrophages isolated from dogs naturally and experimentally infected with -5

<p><b>Copyright information:</b></p><p>Taken from "In vitro binding and survival assays of parasites to peripherical blood monocytes and monocyte-derived macrophages isolated from dogs naturally and experimentally infected with "</p><p>http://www.biomedcentral.com/1746-6148/3/11</p><p>BMC Veterinary Research 2007;3():11-11.</p><p>Published online 30 May 2007</p><p>PMCID:PMC1894629.</p><p></p>e of C5D serum. (C) Promastigotas adhesion with the absence of serum. (D) Note some amastigotas could be seen 48 hours after interaction with the absence of C5D serum Giemsa. 1000×

In vitro binding and survival assays of parasites to peripherical blood monocytes and monocyte-derived macrophages isolated from dogs naturally and experimentally infected with -3

<p><b>Copyright information:</b></p><p>Taken from "In vitro binding and survival assays of parasites to peripherical blood monocytes and monocyte-derived macrophages isolated from dogs naturally and experimentally infected with "</p><p>http://www.biomedcentral.com/1746-6148/3/11</p><p>BMC Veterinary Research 2007;3():11-11.</p><p>Published online 30 May 2007</p><p>PMCID:PMC1894629.</p><p></p>C) CD11b positive cells; (D) CD11b expression during the binding to mononuclear cells with the presence of C5D serum. () CD11b expression during the binding to mononuclear cells with the absence of C5D serum