Article

Robert, J. & Ohta, Y. Comparative and developmental study of the immune system in Xenopus. Dev. Dyn. 238, 1249-1270

Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, USA.
Developmental Dynamics (Impact Factor: 2.38). 06/2009; 238(6):1249-70. DOI: 10.1002/dvdy.21891
Source: PubMed

ABSTRACT

Xenopus laevis is the model of choice for evolutionary, comparative, and developmental studies of immunity, and invaluable research tools including MHC-defined clones, inbred strains, cell lines, and monoclonal antibodies are available for these studies. Recent efforts to use Silurana (Xenopus) tropicalis for genetic analyses have led to the sequencing of the whole genome. Ongoing genome mapping and mutagenesis studies will provide a new dimension to the study of immunity. Here we review what is known about the immune system of X. laevis integrated with available genomic information from S. tropicalis. This review provides compelling evidence for the high degree of similarity and evolutionary conservation between Xenopus and mammalian immune systems. We propose to build a powerful and innovative comparative biomedical model based on modern genetic technologies that takes take advantage of X. laevis and S. tropicalis, as well as the whole Xenopus genus. Developmental Dynamics 238:1249-1270, 2009. (c) 2009 Wiley-Liss, Inc.

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    • "Although metamorphosis is generally rudimentary, or even cryptic in urodelian species (e.g. salamanders, newts), in anuran species it is a major developmental transition between two distinct immune systems [reviewed in (Flajnik et al., 1987; Robert and Ohta, 2009)]. In addition, the different ecological niches occupied by tadpole and adult stages are presumably populated by different pathogens, thus representing unique immunological pressures. "
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    ABSTRACT: Macrophage lineage cells represent the cornerstone of vertebrate physiology and immune defenses. In turn, comparative studies using non-mammalian animal models have revealed that evolutionarily distinct species have adopted diverse molecular and physiological strategies for controlling macrophage development and functions. Notably, amphibian species present a rich array of physiological and environmental adaptations, not to mention the peculiarity of metamorphosis from larval to adult stages of development, involving drastic transformation and differentiation of multiple new tissues. Thus it is not surprising that different amphibian species and their respective tadpole and adult stages have adopted unique hematopoietic strategies. Accordingly and in order to establish a more comprehensive view of these processes, here we review the hematopoietic and monopoietic strategies observed across amphibians, describe the present understanding of the molecular mechanisms driving amphibian, an in particular Xenopus laevis macrophage development and functional polarization, and discuss the roles of macrophage-lineage cells during ranavirus infections.
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    • "This reduction in infection rate may result from the interplay between virus load, which depends on the exposure/re-exposure scenario, and the development of the tadpole immune system over time. Over the course of the larval development, the potential immune response increases in strength, complexity and diversity as the initial innate components are gradually supplemented by the adaptive components of immunity (Robert & Ohta, 2009). In Xenopus, for example, the larvae gradually develop spleen B cells, Lymphopoiesis, lymphocytes and immunoglobulin from Gosner stages 20 to 35 with the maximal immunity reached around Gosner stages 34–35. "
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    • "Xenopus has been and still is one of the top model systems for the study of fundamental questions related to development, immunology, toxicology, neurobiology, embryology and regenerative biology (Du Pasquier et al., 1989; Khokha, 2012; Robert and Ohta, 2009). More recently Xenopus has also been increasingly used as a model for understanding tumor biology, transplantation biology, self tolerance and autoimmunity [reviewed in (Edholm and Robert, 2013). "
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