Abstract: PD01-07
Sources of Funding: This work was supported by Grants from the National Natural Science Foundation of China to (Granted No. 81200548).

Introduction

To explore the function of inflammatory regulation by PD-L1 on the onset and progression of interstitial cystitis (IC).

Methods

The clinical data of IC patients underwent hydrodistension (HD) plus bladder biopsy from 2009 to 2016 at our center were reviewed. The IC was diagnosed as: 1.pressure or pain at bladder accompanied by frequency and nocturia ≥ six weeks; 2. glomerulation or Hunner's ulcer on cystoscopy; 3. exclusion of other disease by pathology. The UPOINT scoring (Urinary symptom, Psychosocial symptom, Organ-specific symptom, Infection, Neurologic symptom and Tenderness) was assessed. HD outcomes were evaluated according to global response assessment (GRA) and UPOINT at postoperative 3 mo. The inflammation degree was semi-quantitatively assessed on Haematoxylin and eosin (H&E) staining. The immunohistochemistry (IHC) for PD-L1 expression dection and immunofluorescence for T cell and B cell counting were performed.

Results

The present study includes 8 males and 32 females with median age of 57 years. The inflammation degree of the bladder wall on H&E is negatively correlated with disease course (P=0.026) and positively correlated with the bladder pain degree (P<0.001). HD is effective at postoperative 3 mo in 19 subjects (GRA≥2), whose UPOINT scores indicate a highest relief rate of the bladder pain (89.5%, 17/19) followed by urinary symptoms (52.6%, 10/19). There are 17, 15, 7 and 1 subjects having none, mild, moderate and high degree of PD-L1 expression (fig. A). And PD-L1 expression degree is correlated with H&E inflammation degree and T cell count (fig. B). Further, PD-L1 expression degree and T cell count are positively correlated with the bladder pain degree (fig. B). Among the 12 subjects with severe inflammation on H&E, HD is more effective for subjects with moderate or high PD-L1 expression (83.3% vs. 16.7%, P=0.04) (fig. C).And subjects with moderate or high PD-L1 expression tended to have more effective hydrodistension outcome than subjects without PD-L1 expression (7/8 vs. 7/17, P=0.038).

Conclusions

PD-L1 expression is more common in IC patients with serious bladder pain and severe bladder inflammation. IC patients with higher degree of PD-L1 expression tend to have more effective HD outcome.

Funding

This work was supported by Grants from the National Natural Science Foundation of China to (Granted No. 81200548).