xenopus mhc class ii molecules. ii. polymorphism as determined by two-dimensional gel electrophoresis.the class ii antigens from four inbred strains of xenopus laevis (r, f, g, and j haplotypes) and six gynogenetic lg clones (two xenopus laevis, two xenopus gilli haplotypes) with functionally well-defined mhc types have been immunoprecipitated with the rabbit anti-human class ii beta-chain serum anti-p29boost and analyzed by two-dimensional gel electrophoresis. the glycosylated material from 15-hr biosynthetically labeled cells runs as a broad fuzzy band around 33kd that, upon removal of n-linke ...19853980992
during frog ontogeny, pha and con a responsiveness of splenocytes precedes that of thymocytes.the in-vitro proliferation of splenocytes and thymocytes from xenopus laevis-gilli (hybrid clone lg-15) to the t cell mitogens, concanavalin a (con a) and phytohaemagglutinin-p (pha), were examined at specific stages of larval development (stages 51-66 of nieuwkoop & faber, 1967) and at 2 months post-metamorphosis. the responses of splenic lymphocytes to each mitogen were significant at all stages with stimulation indices ranging from 1.9 to 50.5 and 2.6 to 45.5 for pha and con a, respectively. ...19846611296
restoration of antibody responsiveness in early thymectomized xenopus by implantation of major histocompatibility complex-mismatched larval thymus.the restorative potential of isogeneic and fully allogeneic thymic implants to restore in vivo antibody responsiveness to a thymus-dependent antigen has been examined in thymectomized clawed toads. isogeneic clones (xenopus laevis/gilli and x. laevis/muelleri hybrids) of known major histocompatability complex (mhc) haplotypes were thymectomized at 5-7 days, implanted with mhc-identical or -mismatched (normal or irradiated ) thymuses from 5-week-old larvae and 4 months later injected with dinitro ...19826749529
the third component of xenopus complement: cdna cloning, structural and functional analysis, and evidence for an alternate c3 transcript.although the third component of complement has been purified from two amphibian species, xenopus laevis and the axolotl, only limited information is available about its primary structure in these species. we now present (a) 95% of the cdna sequence encoding c3 from a xenopus laevis/xenopus gilli (xenopus lg) hybrid (b) an analysis of the c3 convertase and factor i cleavage sites in xenopus c3, and (c) evidence for an alternative form of c3. the xenopus lg sequence has a 57% nucleotide and 52% am ...19957875221
comparative molecular phylogeography of two xenopus species, x. gilli and x. laevis, in the south-western cape province, south africa.xenopus gilli is a vulnerable anuran with a patchy distribution along the south-western coast of the cape province, south africa. this species is sympatric with xenopus laevis laevis, a widespread relative found over much of southern africa. we examined the molecular phylogeography and population structure of the contact zone between these species to obtain information about historical biogeography and conservation management of this region. analyses of the distribution, frequency, and cladistic ...19979131811
optimized transgenesis in xenopus laevis/gilli isogenetic clones for immunological studies.xenopus laevis provides a unique animal model, alternative to mouse, to study immunology. even though, several methodologies have been developed for the generation of transgenic xenopus, to date none have been adapted for the x. laevis/gilli (lg) isogenetic clones that are essential for immunological studies. since lg clones are generated via gynogenesis, transgenic methods using transgene integration into the sperm nuclei are not suited. therefore, we have tested three alternative methods for l ...201121954010
competition and feeding ecology in two sympatric xenopus species (anura: pipidae).the widespread african clawed frog (xenopus laevis) occurs in sympatry with the iucn endangered cape platanna (xenopus gilli) throughout its entire range in the south-western cape, south africa. in order to investigate aspects of the interspecific competition between populations of x. laevis and x. gilli, an assessment of their niche differentiation was conducted through a comprehensive study on food composition and trophic niche structure at two study sites: the cape of good hope (cogh) and kle ...201728439453
limited genomic consequences of hybridization between two african clawed frogs, xenopus gilli and x. laevis (anura: pipidae).the cape platanna, xenopus gilli, an endangered frog, hybridizes with the african clawed frog, x. laevis, in south africa. estimates of the extent of gene flow between these species range from pervasive to rare. efforts have been made in the last 30 years to minimize hybridization between these two species in the west population of x. gilli, but not the east populations. to further explore the impact of hybridization and the efforts to minimize it, we examined molecular variation in one mitochon ...201728439068
semi-solid tumor model in xenopus laevis/gilli cloned tadpoles for intravital study of neovascularization, immune cells and melanophore infiltration.tumors have the ability to grow as a self-sustaining entity within the body. this autonomy is in part accomplished by the tumor cells ability to induce the formation of new blood vessels (angiogenesis) and by controlling cell trafficking inside the tumor mass. these abilities greatly reduce the efficacy of many cancer therapies and pose challenges for the development of more effective cancer treatments. hence, there is a need for animal models suitable for direct microscopy observation of blood ...201525601449
evidence from peptidomic analysis of skin secretions that allopatric populations of xenopus gilli (anura:pipidae) constitute distinct lineages.the international union for conservation of nature (iucn) endangered cape platanna xenopus gilli inhabits disjunct ranges at the tip of cape peninsula and near the town of kleinmond on opposite sides of false bay in the extreme southwest of africa. peptidomic analysis of host-defense peptides in norepinephrine-stimulated skin secretions from frogs from the cape peninsula range resulted in the identification of two magainins, two peptide glycine-leucine-amide (pgla) peptides, two xenopsin-precurs ...201525433327
mind the gaps: investigating the cause of the current range disjunction in the cape platanna, xenopus gilli (anura: pipidae).low-lying areas of the cape at africa's south-westernmost tip have undergone dramatic marine-remodelling, with regular changes in sea-level following glacial cycles. species for which marine barriers are impenetrable underwent concomitant radical distribution changes which may account for current range disjunctions. the cape platanna, xenopus gilli, is a frog distributed in only three disjunt areas within low-lying regions of the southwestern cape. we determined the relationship between frogs fr ...201324109551
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