Cyclosporine monitoring in renal transplant recipients with induction therapy: C2 levels in patients monitored on C0

Could Salivary Cyclosporine Dosage Replace the Whole Blood Cyclosporine Measurements in Renal Transplant Patients?

Background:

Cyclosporin (CsA) has been extensively used as the immunosuppressant of choice in renal transplantation. Currently available approaches to assess CsA levels, both in serum and blood, fail to accurately reflect the concentration of the pharmacologically active drug fraction. Free CsA levels in biological fluids (blood or saliva) have been advocated to play an important role. Traditional salivary CsA monitoring tests are based on available archaic salivary techniques that are nonspecific and require large amounts of saliva. The aim of this study was to assess salivary CsA correlation using a novel and more accurate technique and to correlate with CsA levels in blood.

Material and Methods:

Patients provided blood samples of 2 ml and 2 ml of unstimulated saliva on the same day 2 h after the morning CsA dose (C₂). Whole blood levels of CsA were determined using the monoclonal fluorescent polarization immunoassay (FPIA) kit. The FPIA kit was adapted to salivary testing by using a novel extraction method developed and patented under the name of Middle East Research Institute (MERI). Wilcoxon signed rank test compared the differences in blood and salivary CsA. Pearson's correlation coefficient assessed the linear association between blood and salivary CsA concentrations. All analyses were performed using IBM-SPSS version 23 (IBM Corp, Armonk, NY, USA).

Results:

No significant correlation was observed between blood and salivary CsA levels.

Conclusion:

Salivary CsA concentrations at C₂ cannot adequately replace C₂ blood levels as an indicator of CsA bioavailability despite improved performance of monoclonal FPIA and application of the MERI technique. More studies may be warranted to design more reliable and less invasive procedures for therapeutic drug monitoring.

Matrix metalloproteinases, tissue inhibitors of matrix metalloproteinases, and inflammation in cyclosporine A-induced gingival enlargement: a pilot in vitro study using a three-dimensional model of the human oral mucosa

BACKGROUND

It has been suggested that cyclosporine A (CsA) induces gingival enlargement by promoting an increase in the gingival extracellular matrix (ECM). Nonetheless, the variable occurrence of CsA-induced gingival enlargement in patients receiving this medication indicates a multifactorial pathogenesis. Clinical observations suggest that local inflammation is associated with the development and severity of CsA-induced gingival enlargement. Therefore, the purpose of this study is to investigate the effects of CsA and inflammation on the production of ECM homeostatic mediators.

METHODS

The effects of CsA and inflammation (as assessed using interleukin [IL]-1β) on the secretion of mediators involved in ECM homeostasis were determined using fibroblast monolayers and three-dimensional (3D) models of the human oral mucosa. Fibroblast monolayers and 3D cultures were treated with CsA alone or in combination with IL-1β for up to 72 hours, and the secretion of matrix metalloproteinases (MMPs) 1, 2, 3, 8, 9, 10, and 13 and tissue inhibitors of MMPs (TIMPs) 1, 2, and 4 into the culture medium was assessed using enzyme-linked immunoassay-based antibody arrays.

RESULTS

Fibroblast monolayers responded to CsA with no changes in the secretion of ECM mediators. Conversely, 3D cultures responded to CsA treatment with a reduction in MMP-10 secretion. IL-1β alone triggered higher secretory levels of MMPs in both fibroblast monolayers (MMP-3 and MMP-10) and 3D cultures (MMP-9 and MMP-10). Importantly, fibroblast monolayers and 3D cultures treated with a combination of IL-1β and CsA showed a decrease in the MMP-1/TIMP-1 ratio.

CONCLUSIONS

These data support the hypothesis that inflammation may alter the pathogenesis of CsA-induced gingival enlargement by promoting a synergistic decrease in the MMP-1/TIMP-1 ratio.