IL17 Mediates Pelvic Pain in Experimental Autoimmune Prostatitis (EAP)

<div><p>Chronic pelvic pain syndrome (CPPS) is the most common form of prostatitis, accounting for 90–95% of all diagnoses. It is a complex multi-symptom syndrome with unknown etiology and limited effective treatments. Previous investigations highlight roles for inflammatory mediators in disease progression by correlating levels of cytokines and chemokines with patient reported symptom scores. It is hypothesized that alteration of adaptive immune mechanisms results in autoimmunity and subsequent development of pain. Mouse models of CPPS have been developed to delineate these immune mechanisms driving pain in humans. Using the experimental autoimmune prostatitis (EAP) in C57BL/6 mice model of CPPS we examined the role of CD4+T-cell subsets in the development and maintenance of prostate pain, by tactile allodynia behavioral testing and flow cytometry. In tandem with increased CD4+IL17A+ T-cells upon EAP induction, prophylactic treatment with an anti-IL17 antibody one-day prior to EAP induction prevented the onset of pelvic pain. Therapeutic blockade of IL17 did not reverse pain symptoms indicating that IL17 is essential for development but not maintenance of chronic pain in EAP. Furthermore we identified a cytokine, IL7, to be associated with increased symptom severity in CPPS patients and is increased in patient prostatic secretions and the prostates of EAP mice. IL7 is fundamental to development of IL17 producing cells and plays a role in maturation of auto-reactive T-cells, it is also associated with autoimmune disorders including multiple sclerosis and type-1 diabetes. More recently a growing body of research has pointed to IL17’s role in development of neuropathic and chronic pain. This report presents novel data on the role of CD4+IL17+ T-cells in development and maintenance of pain in EAP and CPPS.</p></div

Increased IL7 in EPS is correlated with patient symptom scores.

<p>A (i-iv) Positive correlation between increasing patient scores and levels of IL7 in EPS. B Negative correlation between Total score and IL1RA. C (i-iii) Positive correlations between each patient score metric. * = p<0.05, ** = p<0.01.</p

IL7 expression is increased in a prostate specific manner in EAP mice.

<p>A (i-iv) QRTPCR of IL7 from murine splenic, bladder, prostate and iliac lymph tissues. B. Immuno-blotting and densitometry for IL7 using prostate tissue lysates. C. Immuno-histochemical staining for IL7, (i-ii) Isotype staining on EAP prostate (iii-iv) IL7 staining on control prostate and (v-vi) IL7 staining on EAP prostate, circle; epithelial, arrowhead; stromal cell staining. Immunoblot densitometry performed in ImageJ using area under the curve values followed by a T-test. Mean +/- SEM are shown, statistics performed in Prism using unpaired T-test, QRTPCR samples normalized to relevant controls with L19 as housekeeping gene and displayed as fold change, performed in technical duplicate and biological triplicate with N = 4/5 mice per group. * = p<0.05, ** = p<0.01.</p

EAP induces pain and expression of IL17 in C57BL/6 mice.

<p>A(i). EAP induces pain as assessed by tactile allodynia Von Frey testing in C57BL/6 mice. Pain is depicted as increased percentage response frequency above baseline every 7 days for 28 days. A(ii-iii), Responses frequencies to filaments on increased force showing increased response as early as day 7 post-EAP induction. B. Flow cytometry staining for T-cell extra and intracellular markers showing increases in CD4+ve IL17+ve cells in both EAP prostate, (i) and iliac lymph node, (iv) tissues compared to controls. Staining for CD4+ve IFNγ (ii, v) cells and CD4+ve CD25+ve FoxP3+ve (iii, vi) show no significant changes between EAP group and controls. Mean +/- SEM is shown, gating was performed as depicted in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0125623#pone.0125623.s001" target="_blank">S1 Fig</a> Flow cytometry experiments are the average of at least two experiments with N = 4/5 mice per group. * = p<0.05, ** = p<0.01.</p

Reproducibility Project: Psychology

Reproducibility is a defining feature of science, but the extent to which it characterizes current research is unknown. We conducted replications of 100 experimental and correlational studies published in three psychology journals using high-powered designs and original materials when available