Seroreactivity toChlamydia trachomatisHsp10 Correlates with Severity of Human Genital Tract Disease

Abstract

We have identified the chlamydial heat shock protein Hsp10 as a potential correlate to the immunopathogenic process in women with tubal factor infertility (TFI). The human serologic response to chlamydial Hsp10, Hsp60, and major outer membrane protein (MOMP) was measured by enzyme-linked immunosorbent assay. Three populations of women were studied: uninfected controls (CU), acutely infected (AI) women, and women with TFI. Sera from women in the AI and TFI groups both recognized Hsp10 more frequently and at a higher overall level than sera from healthy uninfected controls. Moreover, the infertile women had significantly greater Hsp10 seroreactivity than acutely infected women, indicating a concomitant increase of Hsp10 recognition in populations with increasing levels of disease severity. Hsp60 reactivity showed a similar correlation in these populations, while MOMP reactivity peaked at the same level in both AI and TFI populations but did not increase with disease severity. Test populations were standardized by level of reactivity to formalin-fixed Chlamydia trachomatis elementary bodies (EBs) to address whether these associations were reflections of increased overall chlamydial exposure rather than a property specific to Hsp10. Associations between Hsp10 seropositivity and TFI were greater in the EB ؉ subgroup while associations among the EB ؊ subgroup were diminished. When restricted to the EB ؉ subgroups, Hsp60 and MOMP responses in the TFI population did not increase significantly over the level of AI group responses. Thus, among women with similar exposure to chlamydiae, the serologic response to Hsp10 exhibited a stronger correlation with TFI than did the response to Hsp60 or MOMP. These findings support the hypothesis that the serological response to C. trachomatis heat shock proteins is associated with the severity of disease and identifies Hsp10 as an antigen recognized by a significant proportion of women with TFI.

Chlamydial Heat Shock Protein 60 Activates Macrophages and Endothelial Cells Through Toll-Like Receptor 4 and MD2 in a MyD88-Dependent Pathway

“…Chlamydia trachomatis serovar A HSP60, fused with eight additional amino acids (arginine, serine, and six histidine residues) at the carboxyl terminus, was expressed in Escherichia coli, and recombinant protein was purified by affinity chromatography with Ni-NTA resin, as previously described (34). The endotoxin concentration of this preparation was Ͻ0.04 EU/g, as determined by Limulus amebocyte lysate assay (Associates of Cape Cod, Falmouth, MA).…”

“…Recombinant chlamydial HSP60 protein was isolated and purified as described earlier (34). Chlamydia trachomatis serovar A HSP60, fused with eight additional amino acids (arginine, serine, and six histidine residues) at the carboxyl terminus, was expressed in Escherichia coli, and recombinant protein was purified by affinity chromatography with Ni-NTA resin, as previously described (34).…”

Chlamydia Heat Shock Protein 60 Induces Trophoblast Apoptosis through TLR4

“…This preparation of LPS is active on TLR4-transfected HEK 293 cells and not on TLR2 transfectants (S. N. Vogel, unpublished observation). Recombinant chlamydial HSP60 protein was isolated and purified as described earlier (33). C. trachomatis serovar A HSP60, fused with eight additional amino acids (arginine, serine, and six histidine residues) at the C terminus, was expressed in E. coli, and recombinant protein was purified by affinity chromatography with Ni-NTA resin, as previously described (33).…”

“…Recombinant chlamydial HSP60 protein was isolated and purified as described earlier (33). C. trachomatis serovar A HSP60, fused with eight additional amino acids (arginine, serine, and six histidine residues) at the C terminus, was expressed in E. coli, and recombinant protein was purified by affinity chromatography with Ni-NTA resin, as previously described (33). The endotoxin concentration of this preparation was Ͻ0.04 EU/g, as determined by Limulus amebocyte lysate assay (Associates of Cape Cod).…”

Serum Immunoglobulin G Antibodies to Chlamydial Heat Shock Protein 60 but Not to Human and Bacterial Homologs Are Associated With Coronary Artery Disease

“…20 Briefly, Immunolon 2 plates (Dynex Technologies) were coated with 0.5 g of each antigen in PBS for 48 hours at 4°C. After this period, plates were washed 3 times (with wash buffer containing PBS/0.1% Tween 20) using a Labsystems Wellwash 4 Mk 2Ј plate washer and then blocked for 90 minutes at 37°C with PBS/3% ovalbumin (grade II)/0.1% Tween 20.…”