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
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
Cell Biology: Host-parasite cellular and molecular
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
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