Clinical Validation of a Peritoneal Dialysis Prescription Model in the PatientOnLine Software

Peritoneal transport characteristics and residual renal function require regular control and subsequent adjustment of the peritoneal dialysis (PD) prescription. Prescription models shall facilitate the prediction of the outcome of such adaptations for a given patient. In the present study, the prescription model implemented in the PatientOnLine software was validated in patients requiring a prescription change. This multicenter, international prospective cohort study with the aim to validate a PD prescription model included patients treated with continuous ambulatory peritoneal dialysis. Patients were examined with the peritoneal function test (PFT) to determine the outcome of their current prescription and the necessity for a prescription change. For these patients, a new prescription was modeled using the PatientOnLine software (Fresenius Medical Care, Bad Homburg, Germany). Two to four weeks after implementation of the new PD regimen, a second PFT was performed. The validation of the prescription model included 54 patients. Predicted and measured peritoneal Kt/V were 1.52 ± 0.31 and 1.66 ± 0.35, and total (peritoneal + renal) Kt/V values were 1.96 ± 0.48 and 2.06 ± 0.44, respectively. Predicted and measured peritoneal creatinine clearances were 42.9 ± 8.6 and 43.0 ± 8.8 L/1.73 m2/week and total creatinine clearances were 65.3 ± 26.0 and 63.3 ± 21.8 L/1.73 m2/week, respectively. The analysis revealed a Pearson's correlation coefficient for peritoneal Kt/V of 0.911 and Lin's concordance coefficient of 0.829. The value of both coefficients was 0.853 for peritoneal creatinine clearance. Predicted and measured daily net ultrafiltration was 0.77 ± 0.49 and 1.16 ± 0.63 L/24 h, respectively. Pearson's correlation and Lin's concordance coefficient were 0.518 and 0.402, respectively. Predicted and measured peritoneal glucose absorption was 125.8 ± 38.8 and 79.9 ± 30.7 g/24 h, respectively, and Pearson's correlation and Lin's concordance coefficient were 0.914 and 0.477, respectively. With good predictability of peritoneal Kt/V and creatinine clearance, the present model provides support for individual dialysis prescription in clinical practice. Peritoneal glucose absorption and ultrafiltration are less predictable and are likely to be influenced by additional clinical factors to be taken into consideration.

Intravital and whole-organ imaging reveals capture of melanoma-derived antigen by lymph node subcapsular macrophages leading to widespread deposition on follicular dendritic cells.

Aberrant antigens expressed by tumor cells, such as in melanoma, are often associated with humoral immune responses, which may in turn influence tumor progression. Despite recent data showing the central role of adaptive immune responses on cancer spread or control, it remains poorly understood where and how tumor-derived antigen (TDA) induces a humoral immune response in tumor-bearing hosts. Based on our observation of TDA accumulation in B cell areas of lymph nodes (LNs) from melanoma patients, we developed a pre-metastatic B16.F10 melanoma model expressing a fluorescent fusion protein, tandem dimer tomato, as a surrogate TDA. Using intravital two-photon microscopy (2PM) and whole-mount 3D LN imaging of tumor-draining LNs in immunocompetent mice, we report an unexpectedly widespread accumulation of TDA on follicular dendritic cells (FDCs), which were dynamically scanned by circulating B cells. Furthermore, 2PM imaging identified macrophages located in the subcapsular sinus of tumor-draining LNs to capture subcellular TDA-containing particles arriving in afferent lymph. As a consequence, depletion of macrophages or genetic ablation of B cells and FDCs resulted in dramatically reduced TDA capture in tumor-draining LNs. In sum, we identified a major pathway for the induction of humoral responses in a melanoma model, which may be exploitable to manipulate anti-TDA antibody production during cancer immunotherapy.

Comparison of ovarian cancer markers in endometriosis favours HE4 over CA125

Endometriosis is a gynaecological condition with an associated chronic inflammatory response. The ectopic growth of 'lesions', consisting of endometrial cells outside the uterine cavity, stimulates an inflammatory response initiating the activation of macrophages, and resulting in increased cytokine and growth factor concentrations in the peritoneal fluid (PF). Endometriosis‑associated inflammation is chronic and long lasting. In patients with endometriosis, the risk of developing ovarian cancer within 10 years, particularly of the endometrioid or clear cell subtype, is increased 2.5‑4 times. Endometriosis creates a peritoneal environment that exposes the affected endometriotic and the normal ovarian surface epithelial cells to agents that have been suggested to be involved in the pathogenesis of cancer. Concentrations of several cytokines and growth factors were increased in the PF of patients with endometriosis. The ovarian cancer marker, CA125, was one such growth factor; however, this remains to be confirmed. Human epididymis protein 4 (HE4) was detected at high concentrations in patients with ovarian cancer and was identified as the best biomarker for the detection of ovarian cancer. The present study determined the levels of HE4 and CA125 in the peritoneal fluid of 258 patients with and 100 control individuals without endometriosis attending the Department of Obstetrics and Gynaecology, University of Berne (Berne, Switzerland) between 2007 and 2014. The cases were subdivided into groups without hormonal treatment (n=107), or treated with combined oral contraceptives (n=45), continuous gestagens (n=56) or GnRH agonists (n=50). Both of these markers were significantly increased in the non‑treated endometriosis samples compared with the control group. Hormone treatment with either of the three agents mentioned resulted in the concentration of CA125 returning to the control levels and the concentration of HE4 decreasing to below the control levels. CA125, however not HE4, significantly differed between the proliferative and secretory cycle phases. Since HE4 is sensitive to hormonal treatment and robust towards menstrual cycle variation, HE4 is potentially superior to CA125 as an endometriosis marker and therefore has greater potential as a marker for the identification of women at risk of developing ovarian cancer.