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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The course of the disease, cutaneous leishmaniasis, caused by the intracellular protozoan parasite Leishmania tropica, differs markedly amongst various common inbred mouse strains. After intradermal injection of 1 x 10(6) promastigotes to young female specific pathogen-free (SPF) derived mice, persistent infection characterized by an expanding ulcerous lesion is seen in BALB/c and DBA/2 mice. In the strains CBA/H, C3H/He and A/J, lesions resolve within 8 weeks, and in C57B1/6 mice no real lesion typical of cutaneous leishmaniasis develops at the injection site. NZB mice are highly resistant. Macrophages harvested from the thioglycollate-stimulated peritoneal cavity of NZB and C57B1/6 mice appear to differ from macrophages of the other mouse strains in not supporting multiplication of L. tropica organisms in vitro. Nevertheless, hypothymic nude (nu/nu) mice of C57B1/6 genotype, as well as CBA/H-nu/nu and BALB/c-nu/nu mice, develop large lesions with metastases to other cutaneous and visceral locations. In the intact mice in which infection resolves spontaneously, resistance to reinfection is complete. Using mouse antipromastigote sera and an indirect fluorescent antibody test in carefully controlled experiments, L. tropica antigens were detected on in vitro infected macrophages of both highly susceptible BALB/c and relatively resistant CBA/H genotypes. After incubation with a crude soluble antigen preparation from cultured promastigotes, infected BALB/c macrophages differed from infected CBA/H macrophages (and uninfected macrophages of both genotypes) in being unable to sensitize syngeneic recipients for a delayed-type hypersensitivity response to that antigen. When infected and uninfected macrophages were used as "blocking cells" in an in vitro alloreactive cytotoxic T cell system involving cells from congenic mice, evidence was obtained for reduced H-2d expression on infected macrophages of the susceptible mouse strains, BALB/c. The data in this model system of cutaneous leishmaniasis raise the possibility that genetic susceptibility is associated with both a permissive macrophage and defective T cell recognition of parasite antigens on infected macrophages. Defective recognition may be the result of reduced functional expression of H-2d antigens on infected BALB/c macrophages required for efficient recognition by syngeneic T cells of one or more subpopulations.
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PMID:Murine cutaneous leishmaniasis: disease patterns in intact and nude mice of various genotypes and examination of some differences between normal and infected macrophages. 31 86

Quantitative methods for enumerating viable L. enriettii in tissues have been used to determine the course of cutaneous leishmaniasis in guinea-pigs. The development and kinetics of acquired resistance have been evaluated in self-healing and chronic metastatic forms of the disease. It is revealed that 3 weeks after a primary local infection, a standard challenge infection is totally eliminated within 7 days. This resistance is as strong in animals with a current infection as it is in those that have fully recovered from such an infection. Animals developing metastatic disease also develop resistance to the standard challenge. This is initially as strong as in animals with only localized disease, but wanes with the progression of the infection. Although the quality of resistance becomes poorer in animals with metastatic infection, it is not lost completely. The relationship between acquired resistance and the resolution of the primary infection is discussed.
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PMID:The kinetics and quality of acquired resistance in self-healing and metastatic leishmaniasis. 38 Aug 55

Successful immunization of highly susceptible BALB/c mice against progressive infection by Leishmania mexicana amazonensis, using whole solubilized promastigotes was achieved. The best immunization schedule consisted of three weekly injections of 5 X 10(7) parasite equivalents. Intravenous was superior to intraperitoneal or subcutaneous immunization. Protection persisted for up to 2 months after immunization, and beneficial effects could be observed in long-term follow-up (24 weeks after infection). Immunized mice exhibited marked reduction in primary lesion size, as well as reduction of the number of parasites in the spleen, and developed less metastases. High titres of specific anti-L. m. amazonensis IgG antibodies resulted from immunization, but titres did not correlate with protection. Groups with widely differing pre-infection antibody titres were equally protected, and similar antibody titres resulted in different levels of protection. Immunization alone did not induce significant serum interferon-gamma levels and specific delayed-type hypersensitivity (DTH) reactions, but resulted in the persistence of positive (DTH) reactions after infection, at a time when infected control animals had suppressed responses. Resistance to leishmaniasis appears to depend on cell mediated immune mechanisms, and the possibility of immunization with a solubilized antigen without adjuvant is intriguing and opens new perspectives in this area.
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PMID:Specific immunization of mice against Leishmania mexicana amazonensis using solubilized promastigotes. 244 13

A clear understanding of the etiology of the various forms of leishmaniasis will require knowledge of how physiological properties of the parasite and host immunity influence the pattern of development of the disease. Of particular importance are how these factors affect the growth rate of Leishmania spp. at the site of inoculation in the skin, their capacity to disseminate to visceral and distant cutaneous sites, and their capacity to multiply once there. This paper details the pattern of development of disseminated Leishmania major infection in susceptible BALB/c nu/+ and BALB/c nu/nu mice. It was found that the parasite disseminates from the hind footpad to distant cutaneous sites soon after metastatic foci are established in the liver and spleen. Both mononuclear phagocytes and neutrophils may be the vehicles for the transport of the parasite in the blood. Once visceral and cutaneous metastases are established, the parasites in those foci increase in number progressively. L. major has the capacity to multiply at visceral and cutaneous sites at the same rate. Despite the presence of viable parasites in a number of skin sites, cutaneous metastatic lesions developed almost exclusively on the feet and the tail. Furthermore, these lesions appeared to develop preferentially at sites near joints, suggesting that factors other than temperature may influence the development of cutaneous metastatic lesions.
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PMID:Pathophysiology of experimental leishmaniasis: pattern of development of metastatic disease in the susceptible host. 369 85

Highly resistant (C57BL/10) and intermediately resistant (DBA/2) mice were infected subcutaneously with Leishmania mexicana amazonensis in a hind footpad subsequent to removal of the draining popliteal node. These mice developed greatly exacerbated Leishmania infections as compared to sham-operated controls or to mice infected in the contralateral footpad. The majority of mice in which the draining lymph nodes were removed prior to infection developed metastases, lost their delayed hypersensitivity responses to Leishmania, and some died. Significantly fewer metastases and no deaths were observed in the control groups. The results emphasize the importance of lymphatic control of Leishmania m. amazonensis infection in relatively resistant mouse strains.
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PMID:Leishmania mexicana amazonensis infections in 'resistant' inbred mice following removal of the draining lymph node. 373 29

Male B10 X 129 (10M) ScSn mice were relatively resistant to cutaneous leishmaniasis, while females frequently developed non-healing expanding ulcers, leading to loss of infected extremities, metastasis to distal skin sites, and in some animals, death. Anti-leishmanial antibody titers were higher, and delayed-type hypersensitivity responses to parasite antigens, lower, in infected females than in males. Sex differences in response to cutaneous infection were not marked in BALB/cJ mice, a highly susceptible strain, and both males and females ultimately lost infected extremities, developed metastases, and died.
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PMID:Sex-influenced response in the pathogenesis of cutaneous leishmaniasis in mice. 396 May 90

Weanling Sprague-Dawley rats were injected intradermally with Leishmania major or with L. donovani promastigotes. Parasites could be cultivated from the skin at times from 2 to 28 days after infection. At necropsy, no parasites were observed in spleen or liver impression smears, nor could they be cultivated from heart blood or spleen, even when skin cultures were positive. Rats were not highly susceptible to infection with L. donovani, since parasites could be cultured from skin only at 2 days after infection. L. major could establish an infection in rat skin, elicit antibodies, and in some cases, metastasize from the inoculation site. At necropsy, anti-leishmanial antibodies were detected in rats with parasites in their skin, although cutaneous lesions were not observed. These findings suggest that commonly used survey techniques are relatively insensitive, and might indicate possible involvement of Rattus norvegicus in the transmission cycle of cutaneous leishmaniasis.
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PMID:Induction and detection of leishmanial infections in Rattus norvegicus. 408 56

Relatively susceptible BALB/c and relatively resistant A/J mice were infected subcutaneously in the right hind footpad with promastigotes of Leishmania mexicana amazonensis. A large localized lesion developed within 2 months after infection in the BALB/c mice, while A/J mice exhibited a small discrete fibrotic nodule. Sequential immunologic and histologic examination demonstrated that BALB/c mice developed a nodular foam-cell type of lesion and progressive depression of a delayed-type hypersensitivity (DTH) response to leishmania antigen, while the A/J mice had a mixed cellular fibrosing and encapsulating reaction and developed and maintained positive DTH responses to leishmania antigen. Anti-leishmania antibody responses were positive at similar levels in both strains. The lesions in BALB/c mice were found in bone marrow, tendon, skin appendages, and regional lymph nodes, with a tendency toward cutaneous metastases. Lesions in A/J mice remained localized. Fibrosis, focal fibrinoid necrosis, and lymphocytic and macrophagic infiltration were the outstanding features. Light and transmission electron microscopic studies indicated that no outstanding destruction of leishmanias seemed to occur within macrophages of either mouse strain. In the more resistant A/J mice, however, parasitized macrophages were frequently necrotic, and degenerating leishmanias were often seen free in the interstitial tissue. These observations help the interpretation of the histologic features, as well as the pathogenesis, of cutaneous and mucocutaneous leishmaniasis in man.
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PMID:Immunopathology of experimental cutaneous leishmaniasis. 669 11

BALB/c, C57B1/6 and (BALB/c x C57B1/6)F1 mice all proved susceptible to infection by a strain of Leishmania isolated from a Central Brazilian with espundia. The course of disease differed markedly between BALB/c and C57B1/6 mice. BALB/c mice suffered from a rapidly progressive and widely metastatic, but non-ulcerative, disease resembling diffuse cutaneous leishmaniasis. In contrast, C57B1/6 mice initially contained parasite multiplication effectively and appeared clinically cured. However, the parasite could persistently be cultured up to about 1 year post-infection. At that time, the parasite load in the infected footpad increased and a patent disease developed characterized by distinctive ulcerative metastases with destruction of soft-tissue in the nasal region similar to the one observed in espundia. Development of disease in both strains of mice was associated with depression of cell-mediated immunity as monitored by delayed-type hypersensitivity in vivo and lymphocyte transformation in vitro. Thus, our study suggests that diffuse cutaneous leishmaniasis and espundia can be caused by the same strain of parasite, and that the particular clinical expression in the individual mouse is determined by the host response.
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PMID:Late metastatic Leishmaniasis in the mouse. A model for mucocutaneous disease. 683 39

The effect of initiating leishmanial infection in guinea-pigs with organisms contained within macrophages has been examined. Infection of animals in this way resulted in the development of metastatic disease with inocula 2 logs lower than required when free parasites were injected. The macrophage localization was found to protect the parasite from innate resistance, and, at certain times, from mechanisms of acquired immunity. Despite this, initiation of infection with parasites secluded in macrophages did result in the development of specific cell-mediated and humoral immunity. The results indicate that protection of the parasite by the macrophage contributes to the development of metastatic disease. Furthermore, it was revealed that metastatic disease can devlop in the face of acquired mechanisms of resistance. The possibility that non-healing diffuse leishmaniasis is the cause rather than the result of the suppressed immunological reactivity associated with this disease is discussed.
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PMID:Mechanisms of immunity to leishmaniasis. II. Significance of the intramacrophage localization of the parasite. 738 16


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