Publications (2)14.68 Total impact
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Article: Real-time differential labeling of blood, interstitium, and lymphatic and single-field analysis of vasculature dynamics in vivo.
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ABSTRACT: Lymph nodes are highly organized structures specialized for efficient regulation of adaptive immunity. The blood and lymphatic systems within a lymph node play essential roles by providing functionally distinct environments for lymphocyte entry and egress, respectively. Direct imaging and measurement of vascular microenvironments by intravital multiphoton microscopy provide anatomical and mechanistic insights into the essential events of lymphocyte trafficking. Lymphocytes, blood endothelial cells, and lymphatic endothelial cells express sphingosine 1-phosphate receptor 1, a key G protein-coupled receptor regulating cellular egress and a modulator of endothelial permeability. Here we report the development of a differential vascular labeling (DVL) technique in which a single intravenous injection of a fluorescent dextran, in combination with fluorescent semiconductor quantum dot particles, differentially labels multiple blood and lymphatic compartments in a manner dependent on the size of the fluorescent particle used. Thus DVL allows measurement of endothelial integrity in multiple vascular compartments and the affects or pharmacological manipulation in vascular integrity. In addition, this technique allows for real-time observation of lymphocyte trafficking across physiological barriers differentiated by DVL. Last, single-field fluid movement dynamics can be derived, allowing for the simultaneous determination of fluid flow rates in diverse blood and lymphatic compartments.AJP Cell Physiology 02/2012; 302(10):C1460-8. · 3.54 Impact Factor -
Article: Modulating tone: the overture of S1P receptor immunotherapeutics.
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ABSTRACT: Modulation of complex functions within the immune system has proven to be surprisingly sensitive to alterations in the lysophospholipid sphingosine 1-phosphate (S1P) receptor-ligand rheostat. This has become increasingly evident from both chemical and genetic manipulation of the S1P system, with pharmacological effects upon lymphoid cells, dendritic cell function, as well as vascular interfaces. The integrated immune system, perhaps as a result of its relatively recent evolutionary ontogeny, has selected for a number of critical control points regulated by five distinct high affinity G-protein-coupled receptor subtypes with a shared ligand, with receptors distributed on lymphocytes, dendritic cells, and endothelium. All of these cellular components of the axis are capable of modulating immune responses in vivo, with the impact on the immune response being very different from classical immunosuppressants, by virtue of selective spatial and temporal sparing of humoral and myeloid elements of host defense. Pharmacological subversion of the S1P rheostat is proving to be clinically efficacious in multiple sclerosis, and both the scope and limitations of therapeutic modulation of the S1P axis in immunotherapy are becoming clearer as understanding of the integrated chemical physiology of the S1P system emerges.Immunological Reviews 07/2008; 223:221-35. · 11.15 Impact Factor