Welcome to the Jumping Frog Lab
Evolution of Immune Surveillance, Tumor and Viral Immunity
The overall goal of our research is to understand the co-evolutionary aspects of selected molecules (e.g., heat shock proteins [hsps], hsp-receptors [CD91], NK cell receptors [KIR, FcRs], non-classical class Ib molecules [XNCs]) and their functions in innate and adaptive immunity against tumors and viruses. For this purpose, we use the frog, Xenopus laevis, which has proven to provide a unique and versatile model system. Some attributes of this model are: MHC class I deficient but immunocompetent larvae, T-cell-deficient thymectomized animals, minor and major histocompatibility-defined syngeneic clones, and MHC class I-negative and positive transplantable tumor cell lines, and a well-defined virus. Furthermore, our Xenopus experimental model has sufficient evolutionary distance from mammals to permit distinguishing species-specific adaptation or specialization from more fundamental and conserved features of the immune system.
One specific research area addresses the postulated dual role of heat shock proteins (hsps) in innate (signal of danger) and adaptive immunity (T-cell adjuvant). The Xenopus model offers the unique advantage of allowing one to study the immunological properties of hsps in the presence (adult) or absence (tadpole) of classical MHC class I-restricted antigen presentation and, as such, investigate a postulated more general role of hsps as components of an ancestral system of antigen presentation as well as danger signaling . A second area concerns the biological significance of immune cell effector that presents the dual features of adaptive (CD8 and T-cell receptors) and innate (NK receptors) immunity in defense against tumor and virus. This phylogenetic study of early mediators of cellular immunity is complemented by an extensive study of the molecular and genetic evolution of NK receptor families. A last research area concern basic and applied knowledge of viral immunity in amphibians using Xenopus and an iridovirus (FV3) as model.
Current Research Projects
- Negative effects of low dose atrazine exposure on the development of effective immunity to FV3 in Xenopus laevis. Dev Comp Immunol. 47, 52-58. (2014 Jun 28).
- A prominent role for invariant T cells in the amphibian Xenopus laevis tadpoles. Immunogenetics. In press. (2014 Jun 05).
- Unusual evolutionary conservation and further species-specific adaptations of a large family of nonclassical MHC class Ib genes across different degrees of genome ploidy in the amphibian subfamily Xenopodinae. Immunogenetics. 66, 411-26. (2014 Jun 01).