Affiliations:

Doctoral Studies:
Post-doctoral Studies:
Faculty:

State University of New York at Stony Brook
Columbia University, New York, New York
Columbia University, New York, New York
Indiana University, Indianapolis, Indiana

Research Interests:

My laboratory studies endocytic membrane transport in polarized epithelial cells. The function of an epithelium depends upon the polar distribution of transporters and receptors on either the lumenal or basal side of the monolayer. We have shown that endocytosis is critically important to this polarity as the apical and basolateral membranes of epithelial cells are continuously and thoroughly intermixed in endosomes where proteins are sorted for return to the proper domain of the plasma membrane. We have developed powerful methods of quantitative confocal microscopy to address membrane transport in cultured cells labeled with fluorescent conjugates of endocytic ligands and expressing GFP chimeras of endocytic regulatory proteins. 

For the past eleven years I have become increasingly involved in developing quantitative methods of three-dimensional and intravital multiphoton microscopy, a program that has been supported since 2002 by an NIDDK OBrien Center grant.   Along with a group of colleagues from the Nephrology Division, I helped form INphoton, a new company providing intravital microscopy to biotechnology and pharmaceutical companies.  Currently funded by the NIH to develop new methods for characterizing renal drug effects, INphoton has also supported development of methods of quantitative intravital microscopy of the liver, which my laboratory is now using to evaluate the effects of cholestatic drugs on the trafficking and function of hepatocyte transporters in vivo. 

As scientific director of the Indiana Center of Biological Microscopy for the past 15 years, I have worked to expand the effective use of microscopy by IU investigators, and particularly to expand the use of intravital microscopy.  These efforts have resulted in collaborations in which we have developed methods for intravital microscopic analysis of hematopoietic cell biology in the bone marrow, biology of islet cells in the pancreas and in transplants and vascular function in the lung.