A biological role for haemagglutination activity of<i>Leishmania</i>promastigotes and amastigotes

Svobodová, Milena; Capo, C.; Mege, J.M.

doi:10.1051/parasite/1997043245

Cited by 7 publications

(2 citation statements)

References 9 publications

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“…Potential candidates for this receptor are heparin-binding proteins and lectin-like molecules, reported previously in various Leishmania species, some of which occur on the cell surface and bound GalNAc [22-25]. Heparin-binding and lectin-like activities are known to participate in adhesion of Leishmania to host phagocytes [22, 26, 27] and our studies now extend their function into permissive sand fly vectors.…”

Section: Discussionsupporting

confidence: 53%

A lipophosphoglycan-independent development of Leishmania in permissive sand flies

Myšková

Svobodová

Beverley

et al. 2007

Microbes and Infection

110

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Leishmaniases are serious parasitic diseases the etiological organisms of which are transmitted by insect vectors, phlebotominae sand flies. Two sand fly species, Phlebotomus papatasi and P. sergenti, display remarkable specificity for Leishmania parasites they transmit in nature, but many others are broadly permissive to the development of different Leishmania species. Previous studies have suggested that in 'specific' vectors the successful parasite development is mediated by parasite surface glycoconjugates and sand fly lectins, however we show here that interactions involving 'permissive' sand flies utilize another molecules. We did find that the abundant surface glycoconjugate lipophosphoglycan, essential for attachment of Leishmania major in the specific vector P. papatasi, was not required for parasite adherence or survival in the permissive vectors P. arabicus and Lutzomyia longipalpis. Attachment in several permissive sand fly species instead correlated with the presence of midgut glycoproteins bearing terminal N-Acetyl-galactosamine and with the occurrence of a lectin-like activity on Leishmania surface. This new binding modality has important implications to parasite transmission and evolution. It may contribute to the successful spreading of Leishmania due to their adaptation into new vectors, namely transmission of L. infantum by Lutzomyia longipalpis; this event led to the establishment of L.infantum/chagasi in Latin America.

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Section: Discussionsupporting

confidence: 53%

A lipophosphoglycan-independent development of Leishmania in permissive sand flies

Myšková

Svobodová

Beverley

et al. 2007

Microbes and Infection

110

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“…In the case of artiodactyla, whose platelets lack IA receptors (13), this was observed by coincubating sheep serum‐opsonized promastigotes and isolated platelets; no IA reaction was evident (not shown). Unlike serum‐independent trypanosomatid cytoadherence (18) and haemagglutinating activities (19), the physiological nature of Leishmania IA is supported by the quasi‐natural ex vivo conditions of the infection assay and the velocity of the adherence reaction. Taken together, these data indicate that Leishmania IA is a natural phenomenon that constitutes the earliest infection step, and that promastigote–erythrocyte or promastigote–platelet adhesion, respectively, are the first parasite–host cell interactions after invasion if primate and nonprimate mammals.…”

Section: Discussionmentioning

confidence: 99%

Leishmania immune adherence reaction in vertebrates

Domínguez

Toraño

2001

Parasite Immunology

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In normal human blood, C3-opsonized Leishmania promastigotes immune adhere to erythrocytes, a mechanism believed to enhance their clearance from blood and phagocytosis. Given the potential importance of this reaction in host defence against infection, the promastigote-erythrocyte interaction was studied in blood of individuals from one avian and 12 mammalian genera; [111In]-labelled promastigotes were found to bind only to primate erythrocytes. Nevertheless, previous experiments coincubating platelets isolated from nonprimate mammals with C3-opsonized promastigotes led to promastigote-platelet adherence. To ascertain whether this is a natural mechanism in nonprimate Leishmania infection, normal blood from members of Leishmania animal models of interest, dog, guinea-pig, hamster, mouse and rabbit, was infected ex vivo with promastigotes. Within 1 min of blood contact, the promastigote surface was loaded with platelets, rapidly evolving into large aggregates. These results confirm the physiological nature of the reaction and demonstrate that promastigote-erythrocyte and promastigote-platelet binding are the first parasite-host cell encounters after Leishmania invasion of primates and nonprimate mammals, respectively. Leishmania immune adherence shares the characteristics of the nonanticipatory immune systems, and we consider it should be viewed as an innate vertebrate host effector mechanism.

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Redistribution of plasma-membrane surface molecules during formation of the Leishmania amazonensis -containing parasitophorous vacuole

Henriques

Souza²

2000

Parasitology Research

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Leishmania amazonensis presents two developmental stages that gain access to the host macrophage through phagocytosis. The protozoan resides in a membrane-bound compartment, the parasitophorous vacuole (PV), which can fuse with the endocytic system. For evaluation of the parasite/host-cell interaction process and of PV biogenesis, the two parasite forms or host-cell membrane whose surface had previously been labeled with specific probes for lipids, proteins, and sialoglycoconjugates were allowed to interact for periods varying from 5 to 15 min for adhesion and from 30 to 60 min for PV formation. The fate of fluorescent probes was followed by confocal laser scanning microscopy. In host cells previously labeled with PKH26, DTAF and FITC-thiosemicarbazide, which label membrane lipids, proteins, and sialoglycoconjugates, respectively, interaction with both protozoan forms revealed that adhesion to the macrophage was sufficient for labeling of the parasite surface. In addition, recently formed PVs displayed strongly labeled intravacuolar parasites, except for amastigote-macrophage interaction in a DTAF-labeled macrophage that displayed slight labeling of intravacuolar parasites, with the membrane lining the PV evidently being stained. Therefore, the vacuole modulation presents some particularities such that different host-cell membrane components may be selected, depending on the protozoan form involved. Thereafter, amastigotes labeled with the probes mentioned above displayed a diffuse labeling pattern after interaction with unlabeled macrophages, suggesting the spreading of Leishmania surface molecules during the initial parasite-invasion stages. In particular, intravacuolar DTAF-labeled amastigotes showed a delineating halo around the PV, with the intravacuolar parasite being partially labeled. Promastigotes could not be labeled with 5-(4,6-dichlorotriazinyl)aminofluorescein (DTAF) or with fluorescein-5-thiosemicarbazide, but promastigotes labeled with PKH26 lost the fluorescent probe during the invasion process such that slightly labeled promastigotes were seen inside the PV. These observations indicate the existence of a dynamic process of exchange of membrane-associated glycoproteins and lipids between the parasite and the host cell.

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A biological role for haemagglutination activity ofLeishmaniapromastigotes and amastigotes

Cited by 7 publications

References 9 publications

A lipophosphoglycan-independent development of Leishmania in permissive sand flies

A lipophosphoglycan-independent development of Leishmania in permissive sand flies

Leishmania immune adherence reaction in vertebrates

Redistribution of plasma-membrane surface molecules during formation of the Leishmania amazonensis -containing parasitophorous vacuole

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