P4-S1.10 Longitudinal changes in cervicovaginal cytokine levels upon incidentChlamydia trachomatisinfection among young women
Authors: Hwang L Y , Scott M , Ma Y , Jonte J , Moscicki A B 
Published: July 2011

Background

Highest rates of genitalChlamydia trachomatis(CT) infection are found in 15–24-year-old women. Animal, in vitro, and ex vivo studies have identified several inflammatory and regulatory cytokines that impact infection clearance, recurrence, and immunopathology. However, the in vivo natural history of the cytokine response is not well-described. Our study aim was to characterise the cytokine levels in the cervicovaginal secretions of young women with incident CT.

Methods

Women were eligible to enrol (as part of a prospective HPV Natural History Study) who were 13–21 years old, sexually active (5 years maximum), and had no history of cervical neoplasia or procedures, or immunosuppression. Women were seen every 4 months for interviews, infection tests, and cervicovaginal lavage samples for cytokine measurement by Luminex® multiplex assay. CT was detected by nucleic-acid amplification. This prospective study selected women (N=64) who had incident CT infection, defined as a negative CT result followed by a positive CT result at a later visit. Cytokine levels were tested at each woman's pair of negative and positive visits. Each sample was run in duplicate wells. To address assay variation among our samples, per cent-differences between duplicate wells were calculated. A woman's cytokine response was defined as positive” if the per cent-increase from her negative visit to her positive visit exceeded the [mean+2 SD] of the inter-well per cent-difference for that cytokine. Similarly, “negative” was defined as an inter-visit per cent-decrease that exceeded the [mean+2 SD] of the inter-well per cent-difference. The remaining women were defined as having “no response”.

Results

The mean age at incident infection was 19 years. Infections concurrent to the positive CT were detected for HPV in 24 (38%) women; yeast in 10 (16%); bacterial vaginosis in 5 (8%);Neisseria gonorrhoeaein 3 (5%); andTrichomonas vaginalisin 1 (2%). Abstract P4-S1.10 table 1 shows the distribution of cytokine responses. Response status was not significantly associated with age or other genital infections (HPV, yeast, bacterial vaginosis,N gonorrhoeae,T vaginalis) detected at either the negative CT or positive CT visits.

Abstract P4-S1.10 Table 1

Longitudinal changes in cervicovaginal cytokine levels upon incidentChlamydia trachomatisinfection among young women (N=64 women)

CytokineMedian cytokine level at negative CT visit (pg/ml)Median cytokine level at subsequent positive CT visit (pg/ml)Women with positive response, n (%)Women with no response, n (%)Women with negative response, n (%)IL-630.330.323 (36)19 (30)22 (34)IL-81855.51832.68 (16)30 (60)12 (24)IL-1α345.3316.123 (36)14 (22)27 (42)IL-1β29.043.331 (48)14 (22)19 (30)MIP-1α14.119.628 (44)16 (25)20 (31)RANTES3.25.130 (47)22 (34)12 (19)IFNγ3.23.216 (25)43 (67)5 (8)

CT,Chlamydia trachomatis.

Conclusions

In young women with incident CT, the in vivo cytokine responses measured in the cervicovaginal fluid compartment are heterogeneous. Differences in the cytokine milieu between individuals may have implications for immune defense and immunopathology.