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1.
Cytometry A ; 77(5): 420-8, 2010 May.
Article in English | MEDLINE | ID: mdl-20151452

ABSTRACT

In recent years, slide-based cytometry has become a key technology for polychromatic cytometric investigations, and many efforts have been made to increase the number of measurable fluorochromes for multiparametric analysis. Sequential photobleaching of fluorochromes next to very photostable dyes is one approach for this technology. As the ALEXA dyes are known to be photostable as compared to the conventional fluorochromes FITC, PE (Riggs et al., Am J Pathol 1958;34:1081-1097), and APC, a differentiation within a fluorochrome pair is possible. Here, we have analyzed the newly available NorthernLights secondary antibodies for use in slide-based cytometry and microscopy. Currently, these fluorochrome-conjugates are now available with three distinct excitation- and emission maxima (NL493, NL557, NL637). Their spectral properties are similar to the frequently used fluorochromes FITC, PE, and APC and can, therefore, be used with most common excitation sources of cytometers or microscopes. As the NorthernLights are bright, resistant to photobleaching, stable in alcohols and xylene and of affordable price, these dyes are promising candidates for use with most laser- and HBO/XBA-based fluorescence microscopy-like techniques.


Subject(s)
Antibodies/analysis , Flow Cytometry/methods , Fluorescent Dyes/analysis , Microscopy, Fluorescence/methods , Antibodies/chemistry , Cell Line, Tumor , Fluorescein-5-isothiocyanate/metabolism , Humans , Leukocytes/cytology , Leukocytes/radiation effects , Photobleaching/radiation effects , Phycoerythrin/metabolism , Staining and Labeling , Ultraviolet Rays
2.
Cell Prolif ; 41(2): 365-74, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18336479

ABSTRACT

OBJECTIVE: The aim of this study was to establish a preclinical mouse model to study metastases of paediatric rhabdomyosarcoma at the macroscopic and cellular levels, with different imaging methods. EXPERIMENTAL DESIGN: The alveolar rhabdomyosarcoma cell line Rh30 was stably transfected with the red fluorescent protein (DsRed2) then was xenotransplanted (intravenous injection [n = 8], and footpad injection [n = 8]) into nude mice (NMRI nu/nu). Macroscopic imaging of metastases was performed using DsRed2-fluorescence and flat-panel volumetric computed tomography scan. In a further series of animals (n = 8), in vivo cell trafficking of rhabdomyosarcoma cells using cellular imaging with an Olympus OV100 variable-magnification small-animal imaging system was used. RESULTS: Metastases in the pelvis, thoracic wall and skin were visualized by fluorescence imaging. Pelvic metastases were found after tail vein injection and at other metastatic sites after footpad injection. Flat-panel volumetric computed tomography scan data allowed highly specific analysis of contrast between tumour and surrounding tissue. Correlation between fluorescence and flat-panel volumetric computed tomography scan imaging data was observed. Single-cell imaging visualized tumour cells in the vessels and demonstrated the arrest of tumour cells at vessel junctions followed by extravasation of the tumour cells. CONCLUSION: We established a model for visualization of experimental metastatic invasion and describe relevant tools for imaging childhood rhabdomyosarcoma metastases at the macroscopic and cellular levels. Imaging of cell trafficking visualized the behaviour of tumour cells and development of metastases by accumulation and extravasation of rhabdomyosarcoma cells.


Subject(s)
Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Rhabdomyosarcoma/pathology , Rhabdomyosarcoma/secondary , X-Ray Intensifying Screens , Animals , Cell Movement , Cell Proliferation , Disease Models, Animal , Humans , Image Interpretation, Computer-Assisted/instrumentation , Imaging, Three-Dimensional/instrumentation , Luminescent Proteins/chemistry , Mice , Mice, Nude , Microscopy, Fluorescence , Neoplasm Invasiveness , Neoplasm Metastasis , Neovascularization, Pathologic/pathology , Sensitivity and Specificity , Tumor Cells, Cultured , Red Fluorescent Protein
3.
Cytometry A ; 71(8): 542-9, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17598185

ABSTRACT

The multiparametric molecular cell and tissue analysis in vitro and in vivo is characterized by rapid progress in the field of image generation technologies, sensor biotechnology, and computational modeling. Fascinating new potentials in unraveling the detailed functions of single cells, organs, and whole organisms are presently emerging and permit the close monitoring i.e. tumor development or basic cell development processes with an unprecedented multiplicity of promising investigative possibilities. To answer basic questions of in vivo tumor development and progression fluorescence based imaging techniques provide new insights into molecular pathways and targets. Genetic reporter systems (eGFP, DsRED) are available and high sensitive detection systems are on hand. These techniques could be used for in vitro assays and quantified e.g. by microscopy and CCD based readouts. The introduction of novel fluorescent dyes emitting in the near infrared range (NIR) combined with the development of sensitive detector systems and monochromatic powerful NIR-lasers for the first time permits the quantification and imaging of fluorescence and/or bioluminescence in deeper tissues. Laser based techniques particularly in the NIR-range (like two-photon microscopy) offer superb signal to noise ratios, and thus the potential to detect molecular targets in vivo. In combination with flat panel volumetric computed tomography (fpVCT), questions dealing e.g. with tumor size, tumor growth, and angiogenesis/vascularization could be answered noninvasively using the same animal. The resolution of down to 150 microm/each direction can be achieved using fpVCT. It is demonstrated by many groups that submillimeter resolutions can be achieved in small animal imaging at high sensitivity and molecular specificity. Since the resolution in preclinical small animal imaging is down to approximately 10 microm by the use of microCT and to subcellular resolutions using ( approximately 1 microm) microscope based systems, the advances of different techniques can now be combined to "multimodal" preclinical imaging and the possibilities for in vivo intravital cytometry now become within one's reach.


Subject(s)
Diagnostic Imaging/methods , Neoplasms, Experimental/pathology , Animals , Imaging, Three-Dimensional , Magnetic Resonance Imaging , Neoplasms, Experimental/diagnosis , Neoplasms, Experimental/diagnostic imaging , Tomography, X-Ray Computed , Whole Body Imaging
4.
J Wildl Dis ; 27(3): 482-5, 1991 Jul.
Article in English | MEDLINE | ID: mdl-1920670

ABSTRACT

Three hundred thirty-three blue grouse (Dendragapus obscurus) were examined for blood parasites from 11 sites: southern Yukon Territory, southeast coastal Alaska, northern and central interior British Columbia, south coastal British Columbia, northcentral Washington, southcentral Oregon, northwestern California, eastcentral Nevada, northwestern Colorado, and westcentral Montana. Three species of protozoan parasites (Leucocytozoon lovati, Haemoproteus mansoni, Trypanosoma avium) and a splendidofilariid nematode (Microfilaria sp. B) were found in nearly all locations. Prevalence levels were consistently high for L. lovati (92%). The other hematozoa were found less frequently (H. mansoni 29%; T. avium 46%; and microfilaria 29%). The range of these parasites in blue grouse was extended to a more northern (Yukon Territory) and more southern distribution (Nevada than previously reported. Ranges were also extended to blue grouse populations in Alaska, Washington, Oregon and California.


Subject(s)
Bird Diseases/epidemiology , Filariasis/veterinary , Protozoan Infections, Animal , Alaska/epidemiology , Animals , Bird Diseases/blood , Birds , British Columbia/epidemiology , Filariasis/blood , Filariasis/epidemiology , Microfilariae/isolation & purification , Northwestern United States/epidemiology , Prevalence , Protozoan Infections/blood , Protozoan Infections/epidemiology , Southwestern United States/epidemiology , Trypanosoma/isolation & purification , Yukon Territory/epidemiology
5.
Infect Immun ; 57(8): 2283-8, 1989 Aug.
Article in English | MEDLINE | ID: mdl-2744847

ABSTRACT

A neonatal BALB/c mouse model of cryptosporidiosis was used to examine the potential passive transfer of immunity via immune colostrum and oral treatment with anticryptosporidial monoclonal antibodies. Neonates suckled by dams that recovered from Cryptosporidium parvum infections were equally susceptible to infection as their control counterparts suckled by naive dams. Parasite loads among the control and immune colostrum-fed mice were indistinguishable. Neonates receiving orally administered antisporozoite monoclonal antibodies were equally susceptible to infections compared with the control and immune colostrum-fed mice. Parasite loads among the mice receiving daily oral treatment with monoclonal antibody mixtures exhibited significantly lower parasite loads compared with the control mice (P less than 0.05).


Subject(s)
Animals, Newborn/immunology , Antibodies, Monoclonal/administration & dosage , Antibodies, Protozoan/administration & dosage , Coccidia/immunology , Colostrum/immunology , Cryptosporidiosis/immunology , Cryptosporidium/immunology , Administration, Oral , Analysis of Variance , Animals , Antibodies, Protozoan/analysis , Cross Reactions , Cryptosporidiosis/parasitology , Cryptosporidiosis/prevention & control , Cryptosporidium/growth & development , Disease Susceptibility , Mice , Mice, Inbred BALB C
6.
Infect Immun ; 57(1): 146-51, 1989 Jan.
Article in English | MEDLINE | ID: mdl-2521213

ABSTRACT

Mice recovering from a primary infection with an intestinal protozoan parasite, Eimeria falciformis (Apicomplexa: Eimeriidae), showed a classic delayed-type hypersensitivity (DTH) reaction to oocyst antigen challenge. This reaction was characterized by a biphasic pattern of footpad swelling. The first swelling peaked at 2 h after antigen challenge, whereas the second swelling peaked at 24 to 48 h after challenge. The DTH reaction was transferable with a T-cell-enriched spleen cell population from mice that had recovered from E. falciformis infection. Cytotoxic depletion of immune T cells with anti-L3T4 antibody and complement abrogated DTH transfer, indicating that L3T4-positive T cells were required. A T-cell-enriched spleen cell population from acutely infected mice suppressed the transfer of DTH with immune cells from recovered animals, implicating the existence of infection-induced immunoregulatory cells controlling the parasite-specific immune response during infection. Immune spleen cells also transferred resistance to infection as measured by oocyst production and death rate of recipients. Together, these results indicate that the DTH reaction, induced by infection with E. falciformis, is mediated by L3T4-positive T cells and is associated with resistance to infection.


Subject(s)
Coccidiosis/immunology , Hypersensitivity, Delayed/immunology , Acute Disease , Animals , Antigens, Protozoan/immunology , Immunization, Passive , Kinetics , Male , Mice , Mice, Inbred C57BL , Phenotype , Spleen/immunology , T-Lymphocytes/classification , T-Lymphocytes/transplantation , T-Lymphocytes, Regulatory/immunology
7.
Infect Immun ; 56(1): 270-1, 1988 Jan.
Article in English | MEDLINE | ID: mdl-3335404

ABSTRACT

The genetics of the immune response to Eimeria falciformis were investigated in three inbred and six congenic strains of mice. There were significant differences among strains in oocyst production and age-related mortality from parasitic infection. Genes within the H-2 complex and also non-H-2 genes share in the immune response to eimerian infection.


Subject(s)
Eimeria/immunology , H-2 Antigens/genetics , Animals , Coccidiosis/genetics , Coccidiosis/immunology , Coccidiosis/mortality , H-2 Antigens/immunology , Immunity, Innate , Mice , Mice, Inbred BALB C , Mice, Inbred C3H , Mice, Inbred C57BL , Species Specificity
8.
J Protozool ; 34(4): 363-6, 1987 Nov.
Article in English | MEDLINE | ID: mdl-3123644

ABSTRACT

Population dynamics of round and elongate gametocytes of Leucocytozoon in wild and captive blue grouse (Dendragapus obscurus (Say)) from Hardwicke Island, British Columbia, were studied from 1980 to 1982. Blue grouse chicks were sampled weekly throughout each transmission season. Three patterns in the type of gametocyte produced during primary infection were observed in naturally infected captive and wild blue grouse chicks. Such variation in the expression of the gametocyte stage within a single host population suggests a different interpretation than has been previously reported for species of Leucocytozoon. The data from the primary patterns and profiles coupled with reexposure data and the asynchronous appearance of round and elongate gametocytes can be best interpreted as infection with two concurrent species of Leucocytozoon in blue grouse. More detailed research on the life cycle is necessary to confirm if two species of Leucocytozoon exist in blue grouse.


Subject(s)
Apicomplexa/growth & development , Bird Diseases/parasitology , Protozoan Infections, Animal , Animals , Bird Diseases/epidemiology , Birds/parasitology , British Columbia , Protozoan Infections/epidemiology , Protozoan Infections/parasitology , Regression Analysis
9.
Am J Vet Res ; 44(10): 1813-8, 1983 Oct.
Article in English | MEDLINE | ID: mdl-6416114

ABSTRACT

Laboratory-reared dogs were fed moose musculature infected with Sarcocystis alceslatrans. These dogs shed sporocysts [15.6 X 11.4 microns (14.4 to 15.8 X 10.8 to 11.5)] 11 to 15 days after inoculation. The prepatent period was 10 to 14 days. Two cats and 1 coyote that also ate infected moose musculature did not pass sporocysts. Histologic examination of intestinal tissue from experimentally infected dogs revealed microgamonts, macrogametes, and oocysts. All stages were present in the lamina propria of the small intestine, usually in the luminal third of the villi. Infections were concentrated in the proximal half of the small intestine. Oocysts were first noticed in dogs killed 7 days after inoculation and a sequence of sporogonic development occurred in dogs killed on subsequent days. Ultrastructural observations were made on the oocyst and sporocyst walls during sporogony.


Subject(s)
Dogs/parasitology , Intestine, Small/parasitology , Sarcocystis/growth & development , Animals , Carnivora/parasitology , Cats/parasitology , Deer/parasitology , Food Contamination , Intestinal Mucosa/microbiology , Meat , Microscopy, Electron , Sarcocystis/pathogenicity , Sarcocystis/ultrastructure , Species Specificity
11.
Z Parasitenkd ; 65(3): 317-29, 1981.
Article in English | MEDLINE | ID: mdl-6797140

ABSTRACT

Two distinct types of cysts of Sarcocystis from the musculature of moose (Alces alces) were compared by electron microscopy. The fusiform Type A cysts differed from the spherical Type B cysts in the appearance and thickness of the primary cyst wall, organization of cyst interior, and the presence of a secondary cyst wall around Type B. The respective merozoites also differed in size as well as in the number of rhoptries and diameter and arrangement of micronemes. Comparison of the ultrastructure of the moose sarcocysts with those described from other ungulates revealed substantial differences. It appears that two hitherto undescribed species of Sarcocystis are present in moose although cross-transmission and additional life cycle studies are necessary for a complete description.


Subject(s)
Deer/parasitology , Sarcocystis/ultrastructure , Sarcocystosis/veterinary , Alberta , Animals , Cell Wall/ultrastructure , Muscles/parasitology , Sarcocystosis/parasitology
12.
J Wildl Dis ; 16(4): 571-6, 1980 Oct.
Article in English | MEDLINE | ID: mdl-6780701

ABSTRACT

Muscle samples from 557 wild ungulates in Alberta, comprising seven species, were examined grossly and/or histologically for cysts of Sarcocystis. Sarcocystis was found in 100, 96, 94, 75, 75, 73, and 49% of the wapiti (Cervus canadensis), moose (Alces alces), bison (Bison bison), mule deer (Odocoileus hemionus), bighorn sheep (Ovis canadensis), mountain goat (Oreamnos americanus), and white-tailed deer (O. virginianus), respectively.


Subject(s)
Artiodactyla , Sarcocystosis/veterinary , Age Factors , Alberta , Animals , Animals, Wild , Muscles/parasitology , Sarcocystosis/epidemiology , Sarcocystosis/parasitology , Species Specificity , Tongue/parasitology
15.
J Parasitol ; 64(6): 1067-73, 1978 Dec.
Article in English | MEDLINE | ID: mdl-739301

ABSTRACT

The endogenous development of canine Isospora rivolta (Mahrt, J Protozool 14: 754--759, 1967) was compared with the development of I. ohioensis (Dubey, Parasitology, 1978, In press) in intestines of dogs. A new name, Isospora neorivolta, is proposed for the canine I. rivolta because of developmental differences from I. ohioensis. The major difference between these 2 coccidia is their site of development. Isospora neorivolta develops predominantly in the lamina propria of the posterior half of the small intestine, whereas I. ohioensis develops only in the epithelium and infection occurs throughout the small intestine. Additional information on the development of I. neorivolta in dogs is given.


Subject(s)
Dogs/parasitology , Isospora/growth & development , Animals , Cecum/parasitology , Cell Nucleus/ultrastructure , Intestine, Small/parasitology , Isospora/classification , Isospora/ultrastructure
16.
J Wildl Dis ; 13(3): 226-9, 1977 Jul.
Article in English | MEDLINE | ID: mdl-410954

ABSTRACT

Blood films from 60 mallard (Anas platyrhynchos) and 67 pintail (A. acuta) ducks, collected in Alberta and the Mackenzie Delta, Northwest Territories, during 1973 and 1974, were examined for blood parasites. Twenty-two (37%) of the mallards and fourteen (21%) of the pintails were infected with one or more species of hematozoa. Infections of Leucocytozon simondi occurred more frequently (86%) than Haemoproteus nettionis (22%) in the infected birds. Trypanosoma avium occurred in one individual of each species of duck; one pintail harbored an unidentified microfilaria. Differences of prevalence between species are predicted on the basis of host attractancy to vectors and/or host habitat selection, and are discussed.


Subject(s)
Bird Diseases/parasitology , Blood/parasitology , Ducks , Protozoan Infections, Animal , Alberta , Animals , Apicomplexa , Canada , Female , Protozoan Infections/parasitology
19.
C R Acad Hebd Seances Acad Sci D ; 280(18): 2117-9, 1975 May 12.
Article in French | MEDLINE | ID: mdl-807396

ABSTRACT

Ultrastructure of Eimeria nieschulzi unsporulated oocyst is revealed by freeze etching. The two layers of the oocyst wall are observed; they are separated from the multilayered cytoplasmic pellicule by an intraoocystic fluid. Nuclear envelope with pores, endoplasmic reticulum and mitochondrias surrounded by amylopectin granules are easy to identify. This technique makes possible the study of sporulation in Eimeria, which cannot be done with the classical Electron Microscope methods.


Subject(s)
Eimeria/ultrastructure , Animals , Cell Nucleus/ultrastructure , Cytoplasm/ultrastructure , Endoplasmic Reticulum/ultrastructure , Female , Freeze Fracturing , Microscopy, Electron , Mitochondria/ultrastructure
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