Sirolimus and kidney growth in autosomal dominant polycystic kidney disease

BACKGROUND: In autosomal dominant polycystic kidney disease (ADPKD), aberrant activation of the mammalian target of rapamycin (mTOR) pathway is associated with progressive kidney enlargement. The drug sirolimus suppresses mTOR signaling. METHODS: In this 18-month, open-label, randomized, controlled trial, we sought to determine whether sirolimus halts the growth in kidney volume among patients with ADPKD. We randomly assigned 100 patients between the ages of 18 and 40 years to receive either sirolimus (target dose, 2 mg daily) or standard care. All patients had an estimated creatinine clearance of at least 70 ml per minute. Serial magnetic resonance imaging was performed to measure the volume of polycystic kidneys. The primary outcome was total kidney volume at 18 months on blinded assessment. Secondary outcomes were the glomerular filtration rate and urinary albumin excretion rate at 18 months. RESULTS: At randomization, the median total kidney volume was 907 cm(3) (interquartile range, 577 to 1330) in the sirolimus group and 1003 cm(3) (interquartile range, 574 to 1422) in the control group. The median increase over the 18-month period was 99 cm(3) (interquartile range, 43 to 173) in the sirolimus group and 97 cm(3) (interquartile range, 37 to 181) in the control group. At 18 months, the median total kidney volume in the sirolimus group was 102% of that in the control group (95% confidence interval, 99 to 105; P=0.26). The glomerular filtration rate did not differ significantly between the two groups; however, the urinary albumin excretion rate was higher in the sirolimus group. CONCLUSIONS: In adults with ADPKD and early chronic kidney disease, 18 months of treatment with sirolimus did not halt polycystic kidney growth. (ClinicalTrials.gov number, NCT00346918.

Continuous population-level monitoring of SARS-CoV-2 seroprevalence in a large European metropolitan region.

Effective public health measures against SARS-CoV-2 require granular knowledge of population-level immune responses. We developed a Tripartite Automated Blood Immunoassay (TRABI) to assess the IgG response against three SARS-CoV-2 proteins. We used TRABI for continuous seromonitoring of hospital patients and blood donors (n = 72'250) in the canton of Zurich from December 2019 to December 2020 (pre-vaccine period). We found that antibodies waned with a half-life of 75 days, whereas the cumulative incidence rose from 2.3% in June 2020 to 12.2% in mid-December 2020. A follow-up health survey indicated that about 10% of patients infected with wildtype SARS-CoV-2 sustained some symptoms at least twelve months post COVID-19. Crucially, we found no evidence of a difference in long-term complications between those whose infection was symptomatic and those with asymptomatic acute infection. The cohort of asymptomatic SARS-CoV-2-infected subjects represents a resource for the study of chronic and possibly unexpected sequelae

Genetic polymorphisms associated with the inflammatory response in bacterial meningitis

BACKGROUND Bacterial meningitis (BM) is an infectious disease that results in high mortality and morbidity. Despite efficacious antibiotic therapy, neurological sequelae are often observed in patients after disease. Currently, the main challenge in BM treatment is to develop adjuvant therapies that reduce the occurrence of sequelae. In recent papers published by our group, we described the associations between the single nucleotide polymorphisms (SNPs) AADAT +401C > T, APEX1 Asn148Glu, OGG1 Ser326Cys and PARP1 Val762Ala and BM. In this study, we analyzed the associations between the SNPs TNF -308G > A, TNF -857C > T, IL-8 -251A > T and BM and investigated gene-gene interactions, including the SNPs that we published previously. METHODS The study was conducted with 54 BM patients and 110 healthy volunteers (as the control group). The genotypes were investigated via primer-introduced restriction analysis-polymerase chain reaction (PIRA-PCR) or polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) analysis. Allelic and genotypic frequencies were also associated with cytokine and chemokine levels, as measured with the x-MAP method, and cell counts. We analyzed gene-gene interactions among SNPs using the generalized multifactor dimensionality reduction (GMDR) method. RESULTS We did not find significant association between the SNPs TNF -857C > T and IL-8 -251A > T and the disease. However, a higher frequency of the variant allele TNF -308A was observed in the control group, associated with changes in cytokine levels compared to individuals with wild type genotypes, suggesting a possible protective role. In addition, combined inter-gene interaction analysis indicated a significant association between certain genotypes and BM, mainly involving the alleles APEX1 148Glu, IL8 -251 T and AADAT +401 T. These genotypic combinations were shown to affect cyto/chemokine levels and cell counts in CSF samples from BM patients. CONCLUSIONS In conclusion, this study revealed a significant association between genetic variability and altered inflammatory responses, involving important pathways that are activated during BM. This knowledge may be useful for a better understanding of BM pathogenesis and the development of new therapeutic approaches

Transmigration of polymorphnuclear neutrophils and monocytes through the human blood-cerebrospinal fluid barrier after bacterial infection in vitro

Background: Bacterial invasion through the blood-cerebrospinal fluid barrier (BCSFB) during bacterial meningitis causes secretion of proinflammatory cytokines/chemokines followed by the recruitment of leukocytes into the CNS. In this study, we analyzed the cellular and molecular mechanisms of polymorphonuclear neutrophil (PMN) and monocyte transepithelial transmigration (TM) across the BCSFB after bacterial infection. Methods: Using an inverted transwell filter system of human choroid plexus papilloma cells (HIBCPP), we studied leukocyte TM rates, the migration route by immunofluorescence, transmission electron microscopy and focused ion beam/scanning electron microscopy, the secretion of cytokines/chemokines by cytokine bead array and posttranslational modification of the signal regulatory protein (SIRP) α via western blot. Results: PMNs showed a significantly increased TM across HIBCPP after infection with wild-type Neisseria meningitidis (MC58). In contrast, a significantly decreased monocyte transmigration rate after bacterial infection of HIBCPP could be observed. Interestingly, in co-culture experiments with PMNs and monocytes, TM of monocytes was significantly enhanced. Analysis of paracellular permeability and transepithelial electrical resistance confirmed an intact barrier function during leukocyte TM. With the help of the different imaging techniques we could provide evidence for para- as well as for transcellular migrating leukocytes. Further analysis of secreted cytokines/chemokines showed a distinct pattern after stimulation and transmigration of PMNs and monocytes. Moreover, the transmembrane glycoprotein SIRPα was deglycosylated in monocytes, but not in PMNs, after bacterial infection. Conclusions: Our findings demonstrate that PMNs and monoctyes differentially migrate in a human BCSFB model after bacterial infection. Cytokines and chemokines as well as transmembrane proteins such as SIRPα may be involved in this process

Serum concentrations of high-molecular weight adiponectin and their association with sex steroids in premenopausal women

At present, the association between adiponectin and sex hormones in women is controversial. Recent studies suggest that it is high-molecular weight (HMW) adiponectin and the HMW to total adiponectin ratio rather than total adiponectin that are associated with antiatherogenic activities, insulin sensitivity, metabolic syndrome, and prediction of cardiovascular events. The present study aimed to investigate whether measuring HMW adiponectin and the HMW to total adiponectin ratio rather than total adiponectin might be more useful to detect an association between circulating female sex steroids and adipocytokines. In a clinical trial, we investigated the associations of total adiponectin, HMW adiponectin, and the HMW to adiponectin ratio with several androgens and estradiol in 36 healthy premenopausal women with regular cycles. No association between the investigated sex hormones and adiponectin was observed. The HMW adiponectin was negatively correlated with estradiol after adjustment for age and body mass index. The HMW to total adiponectin ratio was significantly negatively associated with testosterone, free testosterone, and androstenedione. The testosterone to estradiol ratio, as a parameter for the estrogen-androgen balance, was not associated with adiponectin or the HMW isoform. In conclusion, there is a negative association between estradiol and HMW adiponectin, and between testosterone, free testosterone, and androstenedione and the HMW to adiponectin ratio. Thus, one mechanism whereby female sex steroids may influence the cardiovascular risk of women could be alteration of the relationship between HMW and total adiponectin concentrations in plasma

Implanon use lowers plasma concentrations of high-molecular-weight adiponectin

OBJECTIVE: To investigate the effect of the low-dosed etonogestrel-releasing contraceptive implant Implanon on new cardiovascular risk markers, we studied the effect of this implant on adiponectin and its metabolically important isomer high-molecular-weight adiponectin (HMW). Low-dosed progestagen-only contraception is preferentially prescribed to females with increased cardiovascular risks. DESIGN: Longitudinal study. SETTING: Family-planning center of a university hospital. PATIENT(S): Forty healthy nonsmoking women with regular cycles (n=20 controls without hormonal contraception; n=20 cases wishing the insertion of Implanon). INTERVENTION(S): Blood samples for the measurements of adiponectin, HMW, C-reactive protein (CRP), sex hormone binding globulin, sexual hormones, and plasma lipids were taken in the early follicular phase of the cycle in both groups. A second sample was taken 12 weeks after Implanon insertion or in the controls during the early follicular phase of cycle four. MAIN OUTCOME MEASURE(S): At baseline there was a significant correlation between adiponectin and the parameters hsCRP and high-density lipoprotein. Implanon treatment caused a significant decrease in HMW and the HMW/adiponectin ratio. Additionally plasma lipids (cholesterol, high-density lipoprotein, low-density lipoprotein), sex hormone binding globulin, and testosterone levels decreased significantly. Adiponectin plasma concentrations were not affected. CONCLUSION(S): Short-term Implanon use in healthy premenopausal women was associated with a decrease in the cardioprotective adiponectin isomer HMW. It remains to be investigated if this decrease persists after longer use of the implant