TLR2 in pleural fluid is modulated by talc particles during pleurodesis

Making cold malignant pleural effusions hot: driving novel immunotherapies

Malignant pleural effusions, arising from either primary mesotheliomas or secondary malignancies, heralds advanced disease and poor prognosis. Current treatments, including therapeutic thoracentesis and tube thoracostomy, are largely palliative. The immunosuppressive environment within the pleural cavity includes myeloid derived suppressor cells, T-regulatory cells, and dysfunctional T cells. The advent of effective immunotherapy with checkpoint inhibitors and adoptive cell therapies for lung cancer and other malignancies suggests a renewed examination of local and systemic therapies for this malady. Prior strategies reporting remarkable success, including instillation of the cytokine interleukin-2, perhaps coupled with checkpoint inhibitors, should be further evaluated in the modern era.

New biomarkers in the selection of patients for talcage of pleural cavity in the palliative therapy of malign pleural exudate

BACKGROUND

Chemical pleurodesis using videothoracoscopically applied powdered talc under general anaesthesia and selective pulmonary ventilation is the most effective method of palliative therapy for malign pleural exudate. Talc produces an intense systemic inflammatory reaction with the development of aseptic pleurisy. The result is obliteration of the pleural cavity provided there is an intense inflammatory reaction in the pleural cavity and good contact of both pleural leaves. The course of the adherence of pleural leaves can be followed using skiascopy. In routine practice, the course of local inflammatory markers is difficult to evaluate. Selection of suitable patients who will respond to this procedure is another principal obstacle of this surgical method.

AIM

To evaluate the course of local inflammatory changes in the pleural cavity following application of talc and to quantify their dynamics. Selection of specific biomarkers to predict the intensity of inflammation in the pleural exudate for targeted selection of patients suitable for talcage was the second aim of this study.

MATERIALS AND METHODS

114 patients were retrospectively divided into Group A (N1 = 98) or patients without relapse and Group B (N2 = 16), patients with relapse of exudate formation. The need for repeated thoracic punctures or drainage over the course of a 12-month monitoring period was a criterion of treatment failure. Quantification of the effusion was performed by ultrasonic examination over a one year observational period at 3-monthly intervals. The concentration of soluble CD163 scavenger receptor and soluble Apo/Fas molecule was determined in exudate by ELISA.

RESULTS

Soluble receptors in the 2 groups differed significantly. Group B showed higher sCD163 levels before talcage (P0 = 0.00024), faster dynamic decline in 2 h (P2 = 0.0092) and in 24 h (P24 = 0.0087). During monitoring, decrease in group B was statistically significant at 2 h (P2 = 0.056) and at 24 hrs (P24 = 0.0066).

CONCLUSION

This pilot study showed that high values of sCD163 and sApo/Fas in the pleural exudate can predict treatment failure. Unsuitable candidates for this type of therapy couldbe selected in this way.

Predictive value of systemic and local inflammation parameters in talc pleurodesis assessment

BACKGROUND

One option for the palliative treatment of recurrent malignant pleural effusion is powdered talc using thoracoscopy. This paper presents the results of selected systemic and local manifestations of the talc-induced inflammatory reaction using a videothoracoscope.

METHOD

A total of 114 patients with repeated malignant pleural effusion were treated at the Cardiac Surgery Clinic in Hradec Kralove from January 2010 to December 2012. Those with a life expectancy more than ≥ 3 months were eligible for talcage surgery. The group was retrospectively divided according to treatment results into Group A (N1 = 98 - successful) and Group B (N2 = 16 - relapsing). The pleural effusion was quantified using ultrasound over 1 year at 3-month intervals. Systemic changes due to the inflammatory reaction (body temperature, serum leukocyte and CRP levels) were evaluated. Local indicators of inflammation included changes in the leukocyte cell population in the effusion and changes in the pleural CRP levels. The dynamics of local expression of membrane receptors TLR-2 and CD-64 on granulocyte and monocyte cell populations in the pleural effusion were also evaluated.

RESULTS

The reaction after talcage, included a significant increase in axillary temperature and leukocyte count, 12 h after the procedure. The dynamics were different in the two groups. The dynamics of local inflammatory changes were an early increase in the pleural CRP levels in both groups. The time interval of local inflammatory development and duration was related to the treatment efficacy and showed a significant rise 2 h after talcage in Group A. In Group B the local inflammatory reaction was slower and the rise was only observed 24 h after talc application. A decrease in lymphocyte count and an increase in granulocyte count 2 h after talcage were found. After an initial drop in monocyte level, a rise occurred within 24 h after talcage. Changes in the expression of TLR-2 and CD-64 receptors in relation to their cell carriers were observed depending on time after talcage.

CONCLUSION

The differences in the serum and pleural effusion CRP levels suggest that the surgical stress manifests itself locally in the pleural space with a lower intensity and time delay. The TLR-2 and CD-64 receptors exhibit different behaviour depending on the type of cell membrane where they are found. The inverse relation between the granulocyte increase and TLR-2 receptor decrease in the membrane immediately after talcage is a new finding. The dynamics of TLR-2 expression on the monocytes demonstrates a direct proportion between the increasing expression of the TLR-2 receptor and increasing percent fraction of the cell carrier.