Therapy of cancer by insect cells containing recombinant baculovirus encoding genes

Provided are compositions and methods of use for insect cells comprising baculovirus encoding non-surface expressed proteins and peptides. The claimed invention particularly relates to compositions comprising insect cells containing baculovirus that express cytokines. Such compositions may be administered by, for example, direct intratumoral injection into tumors in mammals, resulting in tumor reduction or recission. Another aspect of the claimed invention concerns methods of promoting resistance to the reoccurence of tumors in mammals who have undergone such tumor recission. In a specific aspect of the claimed invention, the mammals are human subjects presenting with various forms of cancer.Board of Regents, University of Texas Syste

In vitro culture of the fastidious bacteria Candidatus Liberibacter asiaticus in association with insect feeder cells

Ca. Liberibacter asiaticus (LAS) is vectored by psyllids and is able to proliferate inside the insect. We therefore hypothesize that insect cells could act like feeder cells, providing nutrients in a continuous way and a favorable environment to the bacteria. Various insect cell lines and sources of LAS inoculums were tested in an empiric way to select for the suitable cell line and to establish a protocol for primo-cultures. LAS presence in the inoculated cell cultures was checked by direct PCR and confirmed by sequencing of the amplicons. Nine different cell lines were tested from Mamestra, Spodoptera, Drosophila, Aedes, Diaphorina insects. Mamestra and Spodoptera cell lines were not suitable for LAS growth. Two Drosophila and one Aedes cell lines showed to sustain Liberibacter survival and growth. Diaphorina cell lines were recently received and are under investigation regarding their capacity to maintain the bacteria. To reach higher bacterial concentrations, we analyzed metabolic pathways potentially encoded by the released Ca. Liberibacter genome sequences to define limiting factors and/or growth inhibitors and we complemented the primo-cultures with various additives (sugars, vitamins,...). A culture of LAS was obtained with Aedes cells as feeder cells. This culture has been continuously growing for 9 months and 16 successive transfers. We are currently working on the axenization of this culture. We also succeeded in getting high concentrations of LAS (>106 cells/ml) in an Aedes cell culture + additives and are currently looking into best ways to maintain/increase those concentration levels and to stock those LAS cultures. (Texte intégral

Distribution of glycan motifs at the surface of midgut cells in the cotton leafworm (Spodoptera littoralis) demonstrated by lectin binding

Glycans are involved in many biological phenomena, including signal transduction, cell adhesion, immune response or differentiation. Although a few papers have reported on the role of glycans in the development and proper functioning of the insect midgut, no data are available regarding the localization of the glycan structures on the surface of the cells in the gut of insects. In this paper, we analyzed the spatial distribution of glycans present on the surface of the midgut cells in larvae of the cotton leafworm Spodoptera littoralis, an important agricultural pest insect worldwide. For this purpose, we established primary midgut cell cultures, probed these individual cells that are freely suspended in liquid medium with a selection of seven fluorescently labeled lectins covering a range of different carbohydrate binding specificities [mannose oligomers (GNA and HHA), GalNAc/Gal (RSA and SSA), GlcNAc (WGA and Nictaba) and Neu5Ac(alpha-2,6)Gal/GalNAc (SNA-I)], and visualized the interaction of these lectins with the different zones of the midgut cells using confocal microscopy. Our analysis focused on the typical differentiated columnar cells with a microvillar brush border at their apical side, which are dominantly present in the Lepidopteran midgut and function in food digestion and absorption, and as well as on the undifferentiated stem cells that are important for midgut development and repair. Confocal microscopy analyses showed that the GalNAc/Gal-binding lectins SSA and RSA and the terminal GlcNAc-recognizing WGA bound preferentially to the apical microvillar zone of the differentiated columnar cells as compared to the basolateral pole. The reverse result was observed for the mannose-binding lectins GNA and HHA, as well as Nictaba that binds preferentially to GlcNAc oligomers. Furthermore, differences in lectin binding to the basal and lateral zones of the cell membranes of the columnar cells were apparent. In the midgut stem cells. GNA and Nictaba bound more strongly to the membrane of these undifferentiated cells compared to the microvillar pole of the columnar cells, while SSA, HHA, WGA, and SNA-I showed stronger binding to the microvilli. Our results indicated that polarization of the midgut cells is also reflected by a specific distribution of glycans, especially between the basal and microvillar pole. The data are discussed in relation to the functioning and development of the insect midgut

Understanding the Wolbachia-mediated inhibition of arboviruses in mosquitoes: progress and challenges

Arthropod-borne viruses (arboviruses) pose a considerable threat to human and animal health, yet effective control measures have proven difficult to implement, and novel means of controlling their replication in arthropod vectors, such as mosquitoes, are urgently required. One of the most exciting approaches to emerge from research on arthropods is the use of the endosymbiotic intracellular bacterium Wolbachia to control arbovirus transmission from mosquito to vertebrate. These α-proteobacteria propagate through insects, in part through modulation of host reproduction, thus ensuring spread through species and maintenance in nature. Since it was discovered that Wolbachia endosymbiosis inhibits insect virus replication in Drosophila species, these bacteria have also been shown to inhibit arbovirus replication and spread in mosquitoes. Importantly, it is not clear how these antiviral effects are mediated. This review will summarize recent work and discuss determinants of antiviral effectiveness that may differ between individual Wolbachia/vector/arbovirus interactions. We will also discuss the application of this approach to field settings and the associated risks

Comparison of Encoding Properties of Campaniform Sensilla on the Fly Wing

The wing blade of the blowfly Calliphora vomitoria (L.) carries an array of campaniform sensilla which have previously been divided into slowly and rapidly adapting classes based on their responses to step indentations. In the present study, the physiological characteristics of six sensilla of these two classes are examined within a 20–400 Hz frequency range, using a noise analysis that quantifies linear and nonlinear encoding properties. Both classes exhibit a broad response maximum near 150 Hz, corresponding to the typical wingbeat frequency of the blowfly, and display rectification, limiting the spike response to a narrow portion of a stimulus cycle. The similarity in the encoding properties between the two groups is largely a consequence of the high wingbeat frequency of flies, which precludes any individual neurone from acting as a magnitude detector. Instead, during flight the campaniform neurones might act as ‘one-shot’ detectors, firing a single action potential at a precise phase of each wing stroke cycle. An array of such detectors would be capable of monitoring the passage of a deformational wave as it travels along the wing during each wingbeat

Histopathological effects of cypermethrin and Bacillus thuringiensis var. israelensis on midgut of Chironomus calligraphus larvae (Diptera: Chironomidae)

Pesticides are extensively used for the control of agricultural pests and disease vectors, but they also affect non-target organisms. Cypermethrin (CYP) is a synthetic pyrethroid used worldwide. Otherwise, bioinsecticides like Bacillus thuringiensis var. israelensis (Bti) have received great attention as an environmentally benign and desirable alternative. In order to evaluate the toxicity of those pesticides, Chironomus calligraphus was selected due to its high sensitivity to some toxicants. Third and fourth instars larvae were exposed to serial dilutions of CYP and Bti to determine LC50 values. In order to evaluate the potentially histopathological alterations as biomarkers, after 96-h of exposure, live larvae were fixed for histological analysis of the mid region of digestive tract. The 96-h LC50 values were 0.52 and 1.506 μg/L for CYP and Bti, respectively. Midgut histological structure of the control group showed a single layer of cubical cells with microvilli in their apical surface and a big central nucleus. The midgut epithelium of larvae exposed to a low concentration of CYP (0.037 μg/L) showed secretion activity and vacuolization while at high concentration (0.3 μg/L) cells showed a greater disorganization and a more developed fat body. On the other hand, Bti caused progressive histological damage in this tissue. Chironomus calligraphus is sensitive to Bti and CYP toxicity like other Chironomus species. The histopathological alterations could be a valuable tool to assess toxicity mechanism of different pesticides.Fil: Lavarias, Sabrina Maria Luisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Arrighetti, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Siri, Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; Argentin

Anatomy and Histology of the Male Reproductive Complex of the Onion Maggot Fly, \u3ci\u3eDelia Antiqua\u3c/i\u3e, (Diptera: Anthomyiidae) Including Some Comparisons With \u3ci\u3eD. Platura\u3c/i\u3e and \u3ci\u3eD. Radicum\u3c/i\u3e

In Delia antiqua (Meigen) (Diptera: Anthomyiidae), the male reproductive complex is composed of a pair of testes, paired vas deferens connecting the testes to the anterior ejaculatory duct, and a pair of paragonial (accessory) glands. Each D. antiqua paragonial gland consists of a single layer of secretory epithelial cells surrounded by a thin sheath of muscle tissue. The paragonial cells appear to be largely homogeneous in form, however a minor number of cells exhibit unique staining characteristics distinct from the main cells of the gland. This is preliminary evidence for a secondary cell type as has been found for Drosophila and Aedes paragonial glands. In contrast to the testis and vas deferens, where most of the growth occurs during the pupal stage, the D. antiqua paragonial glands expanded markedly due to secretory accumulation during the first days of adult life. Based on histochemical analyses, the paragonial secretion contained abundant protein, with evidence of glycoprotein. The reproductive complex in all three Delia species (D. antiqua, D. radicum (Bouche) and D. platura (Meigen)) appears similar, with the exception of size differences and timing of paragonial secretory accumulation and sperm maturation. Paragonial glands of D. radicum were the largest in both length and width, and only this species possessed abundant sperm upon eclosion. Of the three species, D. radicum appears most capable of mating immediately after eclosion based on the histology of its reproductive complex, which is consistent with biochemical and behavioral observations made earlier in this laboratory

Immunity in society: diverse solutions to common problems

Understanding how organisms fight infection has been a central focus of scientific research and medicine for the past couple of centuries, and a perennial object of trial and error by humans trying to mitigate the burden of disease. Vaccination success relies upon the exposure of susceptible individuals to pathogen constituents that do not cause (excessive) pathology and that elicit specific immune memory. Mass vaccination allows us to study how immunity operates at the group level; denser populations are more prone to transmitting disease between individuals, but once a critical proportion of the population becomes immune, “herd immunity” emerges. In social species, the combination of behavioural control of infection—e.g., segregation of sick individuals, disposal of the dead, quality assessment of food and water—and aggregation of immune individuals can protect non-immune members from disease. While immune specificity and memory are well understood to underpin immunisation in vertebrates, it has been somewhat surprising to find similar phenomena in invertebrates, which lack the vertebrate molecular mechanisms deemed necessary for immunisation. Indeed, reports showing alternative forms of immune memory are accumulating in invertebrates. In this issue of PLoS Biology, Konrad et al. present an example of fungus-specific immune responses in social ants that lead to the active immunisation of nestmates by infected individuals. These findings join others in showing how organisms evolved diverse mechanisms that fulfil common functions, namely the discrimination between pathogens, the transfer of immunity between related individuals, and the group-level benefits of immunisation