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We describe the expression and consistent production of a first target-specific recombinant human polyclonal antibody. An anti-Rhesus D recombinant polyclonal antibody, Sym001, comprised of 25 unique human IgG1 antibodies, was produced by the novel Sympress expression technology. This strategy is based on site-specific integration of antibody genes in CHO cells, using the FRT/Flp-In recombinase system. This allows integration of the expression construct at the same genomic site in the host cells, thereby reducing genomic position effects. Different bioreactor batches of Sym001 displayed highly consistent manufacturing yield, antibody composition, binding potency, and functional activity. The results demonstrate that diverse recombinant human polyclonal antibody compositions can be reproducibly generated under conditions directly applicable to industrial manufacturing settings and present a first recombinant polyclonal antibody which could be used for treatment of hemolytic disease of the newborn and/or idiopathic thrombocytopenic purpura.

The integration of novel surface-enhanced Raman scattering (SERS) nanoprobes and a microfluidic dielectrophoresis (DEP) device is developed for rapid on-line SERS detection of Salmonella enterica serotype Choleraesuis and Neisseria lactamica. The SERS nanoprobes are prepared by immobilization of specific antibody onto the surface of nanoaggregate-embedded beads (NAEBs), which are silica-coated, dye-induced aggregates of a small number of gold nanoparticles (AuNPs). Each NAEB gives highly enhanced Raman signals owing to the presence of well-defined plasmonic hot spots at junctions between AuNPs. Herein, the on-line SERS detection and accurate identification of suspended bacteria with a detection capability down to a single bacterium has been realized by the NAEB-DEP-Raman spectroscopy biosensing strategy. The practical detection limit with a measurement time of 10 min is estimated to be 70 CFU mL(-1) . In comparison with whole-cell enzyme-linked immunosorbent assay (ELISA), the SERS-nanoprobe-based biosensing method provides advantages of higher sensitivity and requiring lower amount of antibody in the assay (100-fold less). The total assay time including sample pretreatment is less than 2 h. Hence, this sensing strategy is promising for faster and effective on-line multiplex detection of single pathogenic bacterium by using different bioconjugated SERS nanoprobes.

Background Readmission rates are a measure of surgical quality and an object of clinical and regulatory scrutiny. Despite increasing efforts to improve quality and contain cost, 6–25% of patients are readmitted after colorectal surgery. Objective Define predictors and costs of readmission following colorectal surgery. Design Retrospective cohort study of elective and non-elective colectomy and/or proctectomy patients in the Healthcare Cost and Utilization Project Florida State Inpatient Database 2007–2011. Readmission defined as inpatient admission within 30 days of discharge. Univariate analyses of sex, age, Elixhauser score, race, insurance type, procedure, indication, readmission diagnosis, cost, and length of stay. Multivariate analysis performed by logistic regression. Sensitivity analysis of non-emergent admissions. Settings Florida acute care hospitals Patients Colectomy and proctectomy patients 2007–2011 Intervention(s) None Main Outcome Measure(s) Readmission, cost of readmission Results 93,913 patients underwent colectomy. 14.7% were readmitted within 30 days. From 2007 to 2011, readmission rates remained stable (14.6% to 14.2%, trend p=0.1585). After multivariate adjustment, patient factors associated with readmission included non-white race, age <65, and a diagnosis code other than neoplasm or diverticular disease (p<0.0001). Patients with Medicare or Medicaid were more likely to be readmitted than those with private insurance (p<0.0001). Patients with longer index admissions, those with stomas and those undergoing all procedures other than sigmoid or transverse colectomy were more likely to be readmitted (p<0.0001). High volume hospitals had higher rates of readmission (p<0.0001). Most common reason for readmission was infection (32.9%). Median cost of readmission care was $7,030 (IQR $4,220, $13,247). Fistulas caused the most costly readmissions ($15,174; IQR $6,725, $26,660). Limitations Administrative data, retrospective design Conclusions Readmissions rates after colorectal surgery remain common and costly. Non-private insurance, inflammatory bowel disease, and high hospital volume are significantly associated with readmission.

Data from this study supports considering early surgery for pain management in patients with chronic pancreatitis, with the potential of a reduced risk of pancreatic insufficiency and the need for further intervention. Further prospective randomized studies are warranted comparing early surgery against conservative step-up approaches.

Helicobacter pyloriis a common human pathogen that has been identified to be carcinogenic. This study isolated the temperate bacteriophage 1961P from the lysate of a clinical strain ofH. pyloriisolated in Taiwan. The bacteriophage has an icosahedral head and a short tail, typical of thePodoviridaefamily. Its double-stranded DNA genome is 26,836 bp long and has 33 open reading frames. Only 9 of the predicted proteins have homologs of known functions, while the remaining 24 are only similar to unknown proteins encoded byHelicobacterprophages and remnants. Analysis of sequences proximal to the phage-host junctions suggests that 1961P may integrate into the host chromosome via a mechanism similar to that of bacteriophage lambda. In addition, 1961P is capable of generalized transduction. To the best of our knowledge, this is the first report of the isolation, characterization, genome analysis, integration, and transduction of aHelicobacter pyloriphage.

Transcellular transport of a variety of ligands may be an important mechanism by which regulatory substances reach their site of action. We have studied the transcellular transport of two 6,000-mol-wt proteins, epidermal growth factor (EGF) and insulin, across polarized Madin-Darby canine kidney (MDCK) cells grown on dual-sided chambers on a nitrocellulose filter substrate. When grown on these chambers, MDCK cells are polarized and express distinct basal and apical surfaces. MDCK cells are capable of unidirectional transport of EGF from the basal-to-apical direction, 50% of bound EGF transported in 2 h. Transport was inhibited by the addition of unlabeled EGF in a dose-dependent manner. Anti-EGF receptor Ab, which inhibited binding, also inhibited transport. No transport in the apical-to-basal direction is noted. Insulin transport is not observed in either direction. Transport correlates with the presence of ligand-specific receptors on the cell surface. Hence, EGF receptors (Ro = 48,000, Kd = 3.5 X 10(-10) M) are found only on the basal surface of the MDCK cells and neither surface expresses insulin receptors. Characterization of the EGF receptors on MDCK cells, as assessed by affinity, molecular mass, and anti-receptor antibody binding reveals that this receptor has similar characteristics to EGF receptors previously described on a variety of cells. Hence, the EGF receptor can function as a transporter of EGF across an epithelial cell barrier.