Jc. Goodall et al., Identification of Chlamydia trachomatis antigens recognized by human CD4(+) T lymphocytes by screening an expression library, EUR J IMMUN, 31(5), 2001, pp. 1513-1522
Identification of the immunogenic proteins that induce Chlamydia trachomati
s (CT)-specific T cell responses is crucial to the development of protectiv
e vaccines and understanding the mechanisms of chlamydia-induced pathology.
To characterize the targets of the human T cell response we have used chla
mydia-reactive human T cell clones as cellular probes to screen a CT genomi
c library expressed in Escherichia coli using peripheral blood mononuclear
cells to present antigens. The library was screened with three chlamydia-re
active T cell clones of unknown specificity and three novel stimulatory chl
amydia antigens were identified. These E. coli recombinants were shown to e
xpress the chlamydia proteins, enolase, pmpD and CT579. Enolase and pmpD pr
oteins were purified and shown to induce the proliferation of synovial flui
d mononuclear cells isolated from the knee joints of patients suffering fro
m chlamydia-associated reactive arthritis. We suggest that these stimulator
y antigens are common targets of the T cell response in this group of patie
nts. A greater understanding of T cell-mediated immunity in uncomplicated C
T infection, and in patients with CT-induced chronic inflammatory disease (
trachoma, salpingitis, arthritis) may identify the principal immune respons
es associated with immunopathology.