Safety evaluation of a high lipid Whole Algalin Flour (WAF) from Chlorella protothecoides.

Microalgae such as Chlorella spp. have a long history of use in human food. A high lipid Whole Algalin Flour (WAF) composed of dried milled Chlorella protothecoides was evaluated for subchronic toxicity and genotoxic potential. Likelihood of food allergy potential was also evaluated by human repeat-insult patch test. In the subchronic study, rats were fed dietary levels of 25,000, 50,000 or 100,000 ppm WAF in feed for 93-94 days. No mortalities occurred. No treatment-related effects were identified for general condition, body weight, food consumption, ophthalmology, urinalysis, hematology, clinical chemistry, gross pathology, organ weights, and histopathology. Although statistically significant effects were noted for several endpoints, none was test-substance related. The no-observed-adverse-effect level (NOAEL) for WAF was based on consumption of the 100,000 ppm diet, the highest dietary concentration tested, and was 4807 mg/kg bw/d in male rats and 5366 mg/kg bw/d in female rats. Additionally, WAF (≤ 5000 µg/plate) was not mutagenic in Salmonella typhimurium or Escherichia coli tester strains nor did WAF induce a clastogenic response in bone marrow from mice given a single oral dose (2000 mg/kg bw). Further, WAF did not elicit skin sensitization in a repeat-insult dermal patch test which indicates little potential for food allergy.

Analytical Validation of a Highly Quantitative, Sensitive, Accurate, and Reproducible Assay (HERmark) for the Measurement of HER2 Total Protein and HER2 Homodimers in FFPE Breast Cancer Tumor Specimens.

We report here the results of the analytical validation of assays that measure HER2 total protein (H2T) and HER2 homodimer (H2D) expression in Formalin Fixed Paraffin Embedded (FFPE) breast cancer tumors as well as cell line controls. The assays are based on the VeraTag technology platform and are commercially available through a central CAP-accredited clinical reference laboratory. The accuracy of H2T measurements spans a broad dynamic range (2-3 logs) as evaluated by comparison with cross-validating technologies. The measurement of H2T expression demonstrates a sensitivity that is approximately 7-10 times greater than conventional immunohistochemistry (IHC) (HercepTest). The HERmark assay is a quantitative assay that sensitively and reproducibly measures continuous H2T and H2D protein expression levels and therefore may have the potential to stratify patients more accurately with respect to response to HER2-targeted therapies than current methods which rely on semiquantitative protein measurements (IHC) or on indirect assessments of gene amplification (FISH).

Development and characterization of a novel single-cycle recombinant-virus assay to determine human immunodeficiency virus type 1 coreceptor tropism.

Most human immunodeficiency virus type 1 (HIV-1) strains require either the CXCR4 or CCR5 chemokine receptor to efficiently enter cells. Blocking viral binding to these coreceptors is an attractive therapeutic target. Currently, several coreceptor antagonists are being evaluated in clinical trials that require characterization of coreceptor tropism for enrollment. In this report, we describe the development of an automated and accurate procedure for determining HIV-1 coreceptor tropism (Trofile) and its validation for routine laboratory testing. HIV-1 pseudoviruses are generated using full-length env genes derived from patient virus populations. Coreceptor tropism is determined by measuring the abilities of these pseudovirus populations to efficiently infect CD4+/U87 cells expressing either the CXCR4 or CCR5 coreceptor. Viruses exclusively and efficiently infecting CXCR4+/CD4+/U87 cells are designated X4-tropic. Conversely, viruses exclusively and efficiently infecting CCR5+/CD4+/U87 cells are designated R5-tropic. Viruses capable of infecting both CXCR4+/CD4+/U87 and CCR5+/CD4+/U87 cells are designated dual/mixed-tropic. Assay accuracy and reproducibility were established by evaluating the tropisms of well-characterized viruses and the variability among replicate results from samples tested repeatedly. The viral subtype, hepatitis B virus or hepatitis C virus coinfection, and the plasma viral load did not affect assay performance. Minority subpopulations with alternate tropisms were reliably detected when present at 5 to 10%. The plasma viral load above which samples can be amplified efficiently in the Trofile assay is 1,000 copies per ml of plasma. Trofile has been automated for high-throughput use; it can be used to identify patients most likely to benefit from treatment regimens that include a coreceptor inhibitor and to monitor patients on treatment for the emergence of resistant virus populations that switch coreceptor tropism.