Multiplex Cytokine Assay of Cervicovaginal Lavage (CVL) Samples from Women Attending an Urban STD Clinic

Background:
Genital tract immune responses may protect from pathogens or cause harm. Interactions between immunity, flora, and pathogens are not well defined.

Objective:
To apply a targeted multiplex assay to evaluate immune mediators and their inter-relationships with pathogens.

Method:
A CVL specimen and a slide for gram stain were collected from women ≥ 18 years old attending an STD clinic. The cytometric bead array multiplex assay was applied to the CVL specimens. Data analysis was performed by Mann Whitney.

Result:
Eighty-five patients donated CVL specimens. Seventy-seven specimens were tested with the multiplex assay, assessing IL-6, IL-1β and IL-8. Cytokine levels for each clinical diagnosis was compared to levels found in women with a normal clinical exam (n=13). For bacterial vaginosis (BV) diagnosis only (n=11): IL-6, 23 vs. 7 pg/ml (p=.0063); IL-1β, 460 vs. 72 pg/ml (p=.0019); IL-8, 2996 vs. 1320 pg/ml (p=.045). For trichomoniasis diagnosis only (n=5): IL-6, 6 vs. 7 pg/ml (p=.57); IL-1β, 522 vs. 72 pg/ml (p=.009); IL-8, 5000 vs. 1320 pg/ml (p=.011). For all gonorrhea/cervicitis (n=6): IL-6, 473 vs. 7 pg/ml (p=.08); IL-1β, 625 vs. 72 pg/ml (p=.005); IL-8, 3229 vs. 1320 pg/ml (p=.033). The remainder of specimens were mixed infections. The mean assay levels for the entire sample for IL-6, IL-1β, and IL-8 respectively were 112, 609, and 2909 pg/ml.

Conclusion:
The cytokines IL-1β and IL-8 levels were significantly elevated when compared to normal specimens for all clinical diagnoses. IL-6 levels were significantly higher in those with a BV only diagnosis.

Implications:
This preliminary study of local immune response to genital infection demonstrates that all infections studied produce some response while others produce unique patterns of inflammatory cytokines. Further research expanding the number of cytokines and sample size to assess the immune status of the genital tract is needed to develop a predictable test.