scispace - formally typeset
Search or ask a question
Journal ArticleDOI

Frozen sections of arthropods for histological studies and fluorescent antibody investigations.

01 Feb 1961-Experimental Parasitology (Academic Press)-Vol. 11, Iss: 1, pp 50-55
TL;DR: A method for the rapid sectioning of arthropods is described whereby specimens are quick-frozen in gelatin and sectioned in a freezing cabinet at −15 °C and Rickettsia rickettsii was demonstrated successfully in frozen sections prepared from whole ticks.
About: This article is published in Experimental Parasitology.The article was published on 1961-02-01. It has received 8 citations till now. The article focuses on the topics: Ornithodoros moubata.
Citations
More filters
Journal ArticleDOI
TL;DR: Field investigations by Ricketts in western Montana on Rocky Mountain spotted fever established the principal features responsible for the persistence of Rickettsia rickettsii in nature and proved conclusively that the wood tick, bermacentor andersoni, is the vector.
Abstract: Field investigations by Ricketts in western Montana on Rocky Mountain spotted fever established the principal features responsible for the persistence of Rickettsia rickettsii in nature. Unfamiliar with the causative agent, Ricketts proved conclusively that the wood tick, bermacentor andersoni, is the vector. He further demonstrated that the etiologic agent acquired by immature ticks from a variety of small mammals, particularly rodents and lagomorphs, is maintained transstadially and may be transmitted via eggs to the progeny of infected female ticks.* Ricketts’ observations on transovarial infection were based on infectivity of larval ticks derived from females that were infected as adults by feeding on guinea pigs sick with spotted fever. Because no more than half of the females transmitted rickettsiae via eggs, he concluded that under natural conditions, this phenomenon does not occur in more than 50% of infected tick females. He also pointed out that the brood of an infected female may include many uninfected larvae. Although these findings were confirmed by many workers, quantitative data that pertain to transovarial infection did not become available until 1954, when Price reported that transovarial transmission in the field occurs about 30% of the time and that, when it does occur, rickettsiae are not passed to all filial ticks. Unfortunately, experimental data were not given, although the results were based “on a great many studies carried out with several strains of R. rickettsii and several lots of D . andersoni.” In a similar study with a low-virulence strain of R. rickettsii in D . variubilis, the same author found that 30-40% of female ticks that had been infected as larvae and as nymphs by feeding on rickettsemic meadow voles passed rickettsiae to their offspring. Filial infection rates, determined by injection of oviposited eggs and engorged larvae into chick embryos, varied. Fifty percent of the transmitting females laid eggs, of which one of every 10 was infected, 15% showed one of every two to four eggs infected, and 35% had one of every 20-40 eggs infected. Similar results were obtained with engorged filial larval ticks. In contrast to these findings, Burgdorfer reported almost 100% transovarial and filial infection rates for D . andersoni infected either experimentally or naturally with virulent strains of R. rickettsii. Applying direct immunofluorescence to the examination of eggs, larvae, nymphs, and adults, this author found that rickettsia1 infections were retained throughout all developmental stages of the first filial generation and were again passed to 100% of eggs and larvae of the second generation. Since publication of these observations,

156 citations

Journal ArticleDOI
TL;DR: Examination of fluorescent-antibody stained sections of ovarian tissues of infected female ticks revealed the presence of rickettsiae in every ovum; organisms were regularly found in the cytoplasm but never in the nuclei of developing eggs.

35 citations

Journal ArticleDOI
TL;DR: Red-coloured lipid within mites, matching red-colour lipid on outer epidermis, was evidence for the epidermal origin of P. ovis ingesta in the early stages of an infestation.

22 citations

Journal ArticleDOI
TL;DR: The indirect fluorescent-antibody technique was used for the first time to study an insect-microbe association; specifically that existing between the apple maggot, Rhagoletis pomonella, and the apple pathogenic bacterium, Pseudomonas melophthora.

8 citations

Journal ArticleDOI
TL;DR: Mit Hilfe der Fluoreszenzmarkierung von Proteinen und Ouchterlonys Methode wurde festgestellt, dass Insekten keine Immunität besitzen.
Abstract: Mit Hilfe der Fluoreszenzmarkierung von Proteinen und Ouchterlonys Methode wurde festgestellt, dass Insekten keine Immunitat besitzen; Blutserum des Kaninchens blieb wahrend 197 h im Hamolymph der Insekten.

4 citations

References
More filters
Journal ArticleDOI
TL;DR: It was found that each of the three proteins was present in the nuclei of each cell type enumerated above, often in higher concentration than in the cytoplasm, which employs the serological specificity of the protein as a natural "marker".
Abstract: The fate of three proteins, crystalline hen's egg albumin, crystalline bovine plasma albumin, and human plasma gamma-globulin, was traced after intravenous injection into mice. This was done by preparing frozen sections of quick-frozen tissue, allowing what foreign protein might be present in the section to react with homologous antibody labelled with fluorescein, and examining the section under the fluorescence microscope. By this means, which employs the serological specificity of the protein as a natural "marker," all three of these proteins were found in the cells of the reticulo-endothelial system, the connective tissue, the vascular endothelium, the lymphocytes of spleen and lymph node, and the epithelium of the kidney tubules, the liver, and in very small amounts in the adrenal. The central nervous system was not studied. All three persisted longest in the reticulo-endothelial system and the connective tissue, and in the doses employed egg white (10 mg.) was no longer detectable after 1 day, bovine albumin (10 mg.) after 2 days, and human gamma-globulin (4 mg.) after 6 days, although in a somewhat higher dose (10 mg.) human gamma-globulin persisted longer than 8 days. Egg albumin differed from the others in not being detectable in the cells of the renal glomerulus. It was found that each of the three proteins was present in the nuclei of each cell type enumerated above, often in higher concentration than in the cytoplasm. Further, some of the nuclei not only contained antigen, soon after injection, but were also surrounded by a bright ring associated with the nuclear membrane. By means of photographic records under the fluorescence microscope of sections stained for antigen, and direct observation under the light microscope of the same field subsequently stained with hematoxylin and eosin, it could be determined that the antigen was not adsorbed to chromatin or nucleoli, but was apparently in solution in the nuclear sap.

219 citations

Journal ArticleDOI
TL;DR: Although the general arrangement of the musculature in the two families of the Ixodoidea is not fundamentally different, the comparative anatomy of the muscles offers some difficulty, owing to the great morphological differences which the two Families present.
Abstract: The muscular system is so highly developed in the Ixodoidea, that it is no matter of surprise that it has been the subject of more or less detailed treatment in most of the publications dealing with tick anatomy; but, with a single exception, the existing descriptions do not extend beyond a general classification of the various muscles, with the addition of brief remarks, in some instances, on the histological structure of the muscle fibres. In the majority of cases, also, the observations only apply to the Ixodid ticks, and although the general arrangement of the musculature in the two families of the Ixodoidea is not fundamentally different, the comparative anatomy of the muscles offers some difficulty, owing to the great morphological differences which the two families present.

64 citations

Journal ArticleDOI
TL;DR: A fluorescence microscope possessing an efficient ultraviolet light source, the 1000 watt A-H6, is described with special reference to its application in studies concerned with the fluorescent antibody technique and the tissue localization of the tetracyclines.
Abstract: A fluorescence microscope possessing an efficient ultraviolet light source, the 1000 watt A-H6, is described with special reference to its application in studies concerned with the fluorescent antibody technique and the tissue localization of the tetracyclines. The spectral characteristics of the light source are discussed and methods outlined whereby combinations of certain ultraviolet transmitting and absorbing filters can be used for maximum stimulation and visualization of fluorescent substances in tissue specimens. In fluorescent antibody studies when fluorescein isocyanate is used as the fluor, superior results have been obtained by excitation of tissue sections with blue-violet radiation at a wavelength band of 390-440 mµ rather than with ultraviolet radiation at 360-370 mµ. The two outstanding advantages of the longer wavelength stimulation are: 1) The increased fluorescence and consequent visual enhancement; and 2) the greater cellular detail for visual orientation and photographic clarity thus o...

29 citations