Pleural injury and pleurisy‐induced progelatinase B/proMMP‐9 is associated with markers of neutrophil degranulation

Abstract

Objective. Progelatinase B/proMMP‐9 has recently been identified as an indicator of pleural inflammation, presumably originating from granulocytes. The aim of this study was to verify the origin of progelatinase B by simultaneous estimation of specific markers of neutrophil recruitment and activation in pleural effusions following induced pleurisy and pleural injury. Material and methods. Sixty‐three samples of pleural fluid from patients undergoing therapeutic talc pleurodesis (n = 8) and explorative thoracoscopy (n = 3) collected before and at different time intervals after the intervention were analyzed for progelatinase B and neutrophil gelatinase‐associated lipocalin (NGAL)‐gelatinase complex by substrate electrophoresis, for myeloperoxidase (MPO) and interleukin‐8 (IL‐8) by immunoadsorbent sandwich assay, as well as for leukocyte count, C‐reactive protein (CRP) and total protein (TP). Results. A significant increase in free and NGAL‐complexed progelatinase B, MPO and IL‐8 was recorded within 48 h following treatment in all subjects. Progelatinase B was strongly correlated with NGAL‐gelatinase complex (r = 0.88, p = 0.001), MPO (r = 0.81, p = 0.001), neutrophil count (r = 0.75, p = 0.01) and IL‐8 (r = 0.71, p = 0.001), but not with CRP and TP. Conclusions. The results support the neutrophil origin of the proenzyme, which confirms progelatinase B as an indicator of a local inflammatory reaction. Quantifying the inflammatory reaction may be helpful in the evaluation of both the technical variants of therapeutic pleurodesis and finer discrimination of paraneoplastic effusions.