Chicago Medical School/RFUMS
Dr. Chang received his BS in 1965 from the Department of Entomology, National Taiwan University, Taipei, Taiwan, his M.A. in 1968 and his PhD in 1972 in cell biology/endosymbiosis from University of Guelph, Ontario, Canada. He was a postdoctoral fellow in parasitology at Rockefeller University in New York City from 1972 to 1974. He held the position of research associate from 1974 through 1976, assistant professor from 1976 to 1979, and associate professor from 1979 through 1983 at Rockefeller University.
He joined the faculty at Chicago Medical School in 1983 as professor of microbiology and immunology.
Dr. Chang's main research interest is to develop strategies of treatment and prevention for infectious and non-infectious diseases through understanding molecular mechanisms of microbial virulence. Biological models studied include parasitic protozoa in mammalian cells and endosymbiotic bacteria in insects and protozoa.
His work, supported by NIH, has been focused on Leishmania model for microbial virulence. The key concept is the separation of invasive/evasive determinants responsible for infection and pathoantigenic determinants for immunopathology as the manifestation of the disease or virulence phenotype. Leishmania invasive/evasive determinants include enzymes, i.e. zinc protease/major surface glycoprotein (gp63), microsomal glycosyltransferase for protein glycosylation and nucleoside diphosphate kinase. Gp63 expression is regulated posttranslationally by N-glycosylation, which is in turn controlled by the glycosyltransferase gene expression. Secreted nucleoside diphosphate kinase is an evasive determinant to prevent ATP-induced P2X7-mediated apoptosis of macrophages. Other ongoing projects include genetic dissection of the unique metabolic defects, for example, in heme biosynthesis of trypanosomatid protozoa.
Dr. Chang's specific research interests include the following:
Molecular Biology: Structure, regulation and expression of virulence and virulence-regulating genes studied by molecular genetic approach, i.e. gene replacement and transfection.
Biochemistry: Purification and characterization of Leishmania gp63, microsomal N-acetylglucosamine-1-phosphate transferase and nucleoside diphosphate kinase.
Cell Biology: Host-parasite cellular and molecular interactions.
Applied Immunology: Oxidative photo-inactivation of Leishmania spp. for photodynamic vaccination and therapy.
Molecular Epidemiology: Leishmania genotype-phenotype polymorphism in clinical pathology and epidemiology.
His long-term research interests further include:
Evolution, application and function aspects of bacterial endosymbiosis.
Regulation of Leishmania gene expression and vector designs.
Development of photo-medicines for prophylaxis and therapy against infectious and malignant diseases.
Neglected Tropical Diseases - South Asia
Photodynamic vaccination for cancer/mosquitocides