A highly accurate inclusive cancer screening test using Caenorhabditis elegans scent detection.

Early detection and treatment are of vital importance to the successful eradication of various cancers, and development of economical and non-invasive novel cancer screening systems is critical. Previous reports using canine scent detection demonstrated the existence of cancer-specific odours. However, it is difficult to introduce canine scent recognition into clinical practice because of the need to maintain accuracy. In this study, we developed a Nematode Scent Detection Test (NSDT) using Caenorhabditis elegans to provide a novel highly accurate cancer detection system that is economical, painless, rapid and convenient. We demonstrated wild-type C. elegans displayed attractive chemotaxis towards human cancer cell secretions, cancer tissues and urine from cancer patients but avoided control urine; in parallel, the response of the olfactory neurons of C. elegans to the urine from cancer patients was significantly stronger than to control urine. In contrast, G protein α mutants and olfactory neurons-ablated animals were not attracted to cancer patient urine, suggesting that C. elegans senses odours in urine. We tested 242 samples to measure the performance of the NSDT, and found the sensitivity was 95.8%; this is markedly higher than that of other existing tumour markers. Furthermore, the specificity was 95.0%. Importantly, this test was able to diagnose various cancer types tested at the early stage (stage 0 or 1). To conclude, C. elegans scent-based analyses might provide a new strategy to detect and study disease-associated scents.

Urinary tubular biomarkers as potential early predictors of renal allograft rejection.

Confirmation of kidney transplant rejection still requires a histological diagnosis on renal allograft biopsy. Research continues for new non-invasive means for early diagnosis and treatment of kidney allograft rejection. Examination of the urine in renal transplant recipients provides a logical and readily accessible non-invasive window on allograft function, reflecting the function of the kidney in its transplanted environment. Renal tubular epithelial cells (TEC) respond dynamically to the surrounding microenvironment and play an important role in allograft survival. Proteins released from TEC into the urine potentially serve as biomarkers for the early diagnosis of graft dysfunction and rejection. Activated proximal TEC express human leucocyte antigens and co-stimulatory molecules, transiently transforming into non-professional antigen-presenting cells that augment renal allograft rejection. Chemokines and chemoattractants expressed on proximal tubules may also facilitate the migration of alloreactive lymphocytes to local site of injury and stimulate cytokine release from infiltrating lymphocytes. Proximal TEC are also potential targets for circulating alloreactive antibodies and complement leading to cell damage. Changes in cell state during development, regeneration or immune response require a rapid modulation of both surface protein expression and secretion, altering the repertoire of proteins secreted or expressed at the TEC plasma membrane. Due to the proximity of TEC to the tubular lumen, these proteins are passed into the urine. In this regard, TEC possess a unique anatomic location within the transplanted organ and are therefore ideal indicators of graft function. Hence, measurement of the changes of TEC-derived molecules in the urine, in response to different challenges or modification, may predict graft outcome.

GRO alpha in the fetomaternal and amniotic fluid compartments during pregnancy and parturition.

PROBLEM: GRO alpha/MGSA is a new member of the chemokine superfamily CXC(alpha) and is produced by a variety of cells including macrophages, fibroblasts, epithelial, and endothelial cells, and keratinocytes. This chemokine has chemoattractant activity and may participate in neutrophil recruitment and activation during the course of intrauterine infection. This study was conducted to investigate the effect of labor and microbial invasion of the amniotic cavity (MIAC) on amniotic fluid, fetal, and maternal plasma GRO alpha concentrations. METHOD: A cross-sectional study was designed using parameters that included gestational age, results of amniotic fluid (AF) cultures, and labor status at the time of amniocentesis. Fluid was retrieved by transabdominal amniocentesis. MIAC was defined as a positive amniotic fluid culture for bacteria. Umbilical cord blood was retrieved at the time of delivery. Amniotic fluid, maternal and fetal plasma GRO alpha concentrations were measured with a sensitive and specific ELISA (Quantikine, R&D Systems, Minneapolis, MN). RESULTS: 1) GRO alpha was detectable in amniotic fluid, umbilical cord, and maternal plasma samples; 2) GRO alpha concentrations in amniotic fluid increased with advancing gestational age; 3) Both term and preterm gestations with MIAC were associated with higher amniotic fluid GRO alpha concentrations than those with sterile amniotic fluid, independent of the labor status (term, MIAC, labor: median 2.7 ng/ml, range 1.4-12.7 vs. term, no MIAC, labor: median 2.1 ng/ml, range 0.7-3.4, vs term, no MIAC, no labor: median 1.9 ng/ml, range 1.8-4.2; P < 0.005; preterm: MIAC median 5 ng/ml, range 0.6-47.9 vs. no MIAC: median 2.3 ng/ml, range 0.5-10; P < 0.008); 4) A strong correlation was found between umbilical cord plasma GRO alpha concentrations and neonatal neutrophil count, and between GRO alpha concentrations and white blood cell count in the amniotic fluid (r = 0.67, P < 0.0005 and r = 0.38, P < 0.001, respectively). CONCLUSION: GRO alpha is a physiologic constituent of amniotic fluid and cord blood. Amniotic fluid GRO alpha concentrations increase with gestational age. Intrauterine infection both preterm and at term is associated with an increase in GRO alpha concentrations of amniotic fluid, suggesting that GRO alpha may play an important role in recruitment of neutrophils into the amniotic cavity.

Inflammatory mediator profile in urine and bladder wash fluid of patients with interstitial cystitis.

Interstitial cystitis is a syndrome of urinary urgency, frequency and suprapubic pain. We investigated the role of inflammatory mediators in 96 patients with histories and symptoms consistent with interstitial cystitis, and 13 controls from The New York Hospital-Cornell Medical Center, University of Washington and University of California at San Diego. Patients were classified into either group A (meets all criteria of the National Institute of Arthritis, Diabetes, Digestive and Kidney Diseases for inclusion in research studies), group B (meets all of these criteria but without glomerulations) or an "other" group. A small number of group A patients had detectable interleukin-6 in the urine. Urinary concentrations of tumor necrosis factor, prostaglandins E2, D2 and F2 alpha, and thromboxane B2 were not different among either patient groups or controls. Urine specimens contained inhibitors of the bioactivity of interleukin-6 and tumor necrosis factors but no differences between patients or controls were found. No factors chemotactic for human neutrophils were detected in a small patient sample. Bladder wash fluid concentrations of prostaglandins E2, D2 and F2 alpha, and thromboxane were much lower than urinary levels. Bladder wash fluid interleukin-6 and tumor necrosis factor were not detectable. The results suggest that while a small subset of patients may have elevated levels of interleukin-6 the majority of patients do not appear to have elevated levels of inflammatory mediators in the urine or bladder wash fluid. Evaluation of patient bladder tissue may indicate changes not detectable in urine or bladder wash fluid. Alternatively, other etiologies must be considered in those patients.

Detection of monocyte chemotactic and activating factor (MCAF) in normal blood and urine using a sensitive ELISA.

We developed a highly sensitive enzyme-linked immunosorbent assay (ELISA) for human monocyte chemotactic and activating factor (MCAF), an inflammatory cytokine that plays an important role in the recruitment of blood monocytes to areas of inflammation. The ELISA, which is based on a sandwich method using two newly-developed monoclonal antibodies, could quantitatively detect MCAF in the range between 2.5 pg/ml (50 fg/sample) to 300 pg/ml after incubation for a total of 2 h, and showed no cross-reactivity with various structurally-related IL-8 superfamily proteins. It was not affected by blood or urine components non-specifically, and thus was directly applicable to clinical specimens. When serum and urine samples from healthy subjects were measured, they all turned out to contain detectable levels of MCAF (more than 30 pg/ml). By gel-filtration column chromatography analysis, MCAF in the body fluids was eluted as a single peak at the position corresponding to the molecular weight of 10 kD, suggesting that it exists as a monomer form, free from carrier proteins. The established ELISA here is expected to be effectively used for the further investigations on the relationship of MCAF with various inflammatory diseases.

Chemotactic factors as cause of polyleukocyte urine in urinary tract infection: chemotactic activity of urinary protein fraction.

The possible cause of the excessive increase in the number of polymorphonuclear leukocytes in the urine of patients suffering from urinary tract infections was investigated in regard to the chemotactic factor(s) for the leukocyte. We separated urinary protein fractions of 2 controls and 10 patients with urinary tract infections by gel filtration on a Sephadex G-50 column, and tested chemotactic activity in vitro by using Boyden's apparatus and in vivo by injecting the protein fractions into guinea pig skins. Chemotactic activity was found in the urinary protein fractions of 6 patients. The fractions of these 6 patients showed typical infiltration of polymorphonuclear leukocytes in the local tissue of guinea pigs. A high correlation was found between the activity and the leukocyte increase, although there was no relation between the type of infecting bacteria and chemotactic activity. The data suggest that the marked increase in the number of urinary leukocytes is attributable to the chemotactic factor(s) in the urine.