Safety and Pharmacokinetic Assessments of a Novel Ivermectin Nasal Spray Formulation in a Pig Model.

Recently published data indicates that high ivermectin (IVM) concentrations suppress in vitro SARS-CoV-2 replication. Nasal IVM spray administration may contribute to attaining high drug concentrations in nasopharyngeal tissue, a primary site of virus entrance/replication. The safety and pharmacokinetic performances of a novel IVM spray formulation were assessed in a pig model.

Natural Killer Cells for Immunotherapy - Advantages of the NK-92 Cell Line over Blood NK Cells.

Natural killer (NK) cells are potent cytotoxic effector cells for cancer therapy and potentially for severe viral infections. However, there are technical challenges to obtain sufficient numbers of functionally active NK cells from a patient's blood since they represent only 10% of the lymphocytes and are often dysfunctional. The alternative is to obtain cells from a healthy donor, which requires depletion of the allogeneic T cells to prevent graft-versus-host reactions.

Impact of gene patents on the development of molecular diagnostics.

There is a widely held view that gene patents in particular and patents in general, because of the exclusionary rights that they provide, are inhibiting the development of and access to critical molecular diagnostic testing. This is a highly relevant issue for healthcare delivery as we move towards personalized medicine, which relies heavily on genetic testing to tailor treatments that are specific for individual characteristics. Critics of the patent system hope to void or diminish the exclusionary aspect of patents by removing genes from the definition of what is patentable, by increasing the number of activities that fall within the research use exemption, or by compelling patent holders to license their rights non-exclusively.

Academic technology transfer and radiology: a strong partnership for the future.

To date, technology transfer from academia to industry has been strongest in the biotechnology and pharmaceutical sector. The medical imaging and medical device industries have traditionally been smaller players and, as a result, some, perhaps many, investigators in radiology are unaware of the potential value of technology transfer and the opportunity to receive sponsorship for research from medical imaging companies. Many investigators are also unaware of opportunities to introduce important academic discoveries into clinical practice through licensing and technology transfer.

T-cell presentation of antigen requires cell-to-cell contact for proliferation and anergy induction. Differential MHC requirements for superantigen and autoantigen.

MHC class II+ human T-cell clones are able to simultaneously present and respond to peptide Ag and superantigen resulting in both proliferation and subsequent anergy. A major question remains as to whether a single T cell can present to itself or whether T-T cell interactions are required. We have employed a novel technique for inhibiting cell-to-cell contact that encapsulates individual T cells in agarose gel microdrops.

Effect of different promoters on expression of genes introduced into hematopoietic and marrow stromal cells by electroporation.

Electroporation is a simple and relatively efficient means of introducing genes into hematopoietic cells. However, achieving and maintaining high levels of gene expression in transfected hematopoietic progenitor cells remains problematic. In order to address this problem we examined the effect of different viral and cellular promoters on the transient expression of reporter genes transferred into K562, KG1a, and human marrow stromal cells.

Gene transfer by electroporation: a model for gene therapy.

We examined electroporation for the introduction of DNA into hematopoietic cells in order to develop an in vitro model for human gene therapy. We demonstrated that electroporation is a relatively efficient and reproducible method of gene transfer in permanent hematopoietic lines. Characterization of DNA transfer revealed that genes are integrated in single or low copy number.

A system for on-line detection and resolution of radiolabeled DNA molecules and its application to automated DNA sequence analysis.

We describe a system for the real-time detection of radioactively labeled DNA molecules in gel matrix, and we demonstrate the application of this system to DNA sequence analysis. DNA sequencing reactions prepared by the Sanger chain termination method are resolved by electrophoresis on 8% polyacrylamide gels. During electrophoresis the 32P-labeled DNA fragments are detected by solid state detectors positioned 22 cm from the top surface of the gel.

Electric field-mediated gene transfer: characterization of DNA transfer and patterns of integration in lymphoid cells.

Southern analysis of individual transfectants generated by electroporation demonstrated a strong preference for the integration of DNA in low copy number even when electroporation was performed in the presence of increasing DNA concentrations. Although transfer of multiple DNA copies was detected at higher DNA concentrations (16 pmoles/ml or greater), the average gene copy number even at 36 pmoles DNA per ml, was only 13. Multiple gene copies were integrated at either a few chromosomal sites, or at a single site within individual transfectants.

Use of a chemically modified T7 DNA polymerase for manual and automated sequencing of supercoiled DNA.

Procedures are presented for reliable and accurate nucleotide sequence analysis using as template supercoiled DNA prepared by a modified rapid boiling minipreparation protocol. This method yields DNA templates suitable for sequencing within 1 h of bacterial harvest. We describe optimal reaction conditions for supercoiled miniprep DNA sequencing using a modified T7 DNA polymerase (Sequenase) in dideoxynucleotide chain termination reactions.

A genetically engineered murine/human chimeric antibody retains specificity for human tumor-associated antigen.

Chimeric immunoglobulin genes were constructed by fusing murine variable region exons to human constant region exons. The ultimate goal was to produce an antibody capable of escaping surveillance by the human immune system while retaining the tumor specificity of a murine monoclonal. The murine variable regions were isolated from the functionally expressed kappa and gamma 1 immunoglobulin genes of the murine hybridoma cell line B6.

Stable expression of selectable genes introduced into human hematopoietic stem cells by electric field-mediated DNA transfer.

The successful introduction of DNA into human bone marrow cells by electric field-mediated transfer was initially demonstrated by the detection of transient chloramphenicol acetyltransferase (acetyl-CoA:chloramphenicol O3-acetyltransferase, EC 2,3.1.28) activity in marrow cell extracts.

Electric field-mediated DNA transfer: transient and stable gene expression in human and mouse lymphoid cells.

The technique of DNA transfer by electroporation was investigated in an effort to evaluate its utility for the identification of developmentally controlled regulatory sequences. Transient and stable gene expression was detected in a variety of lymphoid cell lines subjected to electroporation. No correlation existed between the levels of chloramphenicol acetyltransferase (acetyl-CoA; chloramphenicol 3-O-acetyltransferase, EC 2.

Viral membrane glycoproteins: comparison of the amino terminal amino acid sequences of the precursor and mature glycoproteins of three serotypes of vesicular stomatitis virus.

The NH2-terminal amino acid sequences of the envelope glycoproteins and the in vitro synthesized, nonglycosylated precursors of the glycoproteins of three serotypes, namely Indiana (Toronto), Cocal, and New Jersey (Concan) of vesicular stomatitis virus were determined. A comparison of the sequences showed little homology in the signal peptides present in the nonglycosylated precursors except for their high hydrophobic amino acid content. In contrast, the NH2-terminal amino acid sequences of the mature envelope glycoproteins revealed extensive homology suggesting that this region is conserved and may be involved in essential biological function(s) of the rhabdovirus.

Synthesis and assembly of membrane glycoproteins. Membrane anchoring COOH-terminal domain of vesicular stomatitis virus envelope glycoprotein G contains fatty acids.

Two polypeptides associated with the envelope of vesicular stomatitis virus are obtained by exhaustive proteolytic digestion of the virion. Analysis of the tryptic peptides and determination of the partial amino acid sequence show that the larger membrane-anchoring peptide is derived from the hydrophobic COOH terminus of the viral transmembrane glycoprotein G. The smaller peptide is, however, derived from the nonglycosylated matrix protein M.

Synthesis and assembly of membrane glycoproteins: presence of leader peptide in nonglycosylated precursor of membrane glycoprotein of vesicular stomatitis virus.

Translation of mRNA encoding vesicular stomatitis virus envelope glycoprotein G by as membrane-free ribosomal extract obtained from HeLa cells yielded a nonglycosylated protein (G1 (Mr 63,000). In the presence of added microsomal membranes, G1 was converted to the glycosylated protein (G2 (Mr 67,000) which is inserted in the membrane vesicles as a transmembrane protein. Labeling with methionine donated by wheat germ initiator tRNA1Met showed that G1 but not G2 contains methionine in the NH2-terminal position.

In vitro synthesis of vesicular stomatitis virus membrane glycoprotein and insertion into membranes.

Translation in vitro of the mRNA coding for the vesicular stomatitis virus membrane glycoprotein G in a membrane-free ribosomal extract from HeLa cells allowed the synthesis of only the unglycosylated protein G1 (molecular weight, 63,000). Addition of stripped crude microsomal membranes from HeLa cells resulted in the conversion of G1 to the glycosylated protein G2 (molecular weight, 67,000). The G2 protein synthesized by the reconstructed microsomal membrane/ribosome system was found to be segregated inside the microsomal membrane vesicles and was thus protected from the proteolytic action of trypsin and chymotrypsin.

Synthesis and glycosylation in vitro of glycoprotein of vesicular stomatitis virus.

Coupling of ribonucleoprotein particles from L cells infected with vesicular stomatitis virus to a pre-incubated ribosomal system obtained from uninfected HeLa cells allowed synthesis of two proteins. G1 (molecular weight 63,000) and G2 (molecular weight 67,000), and all other proteins of vesicular stomatitis virus except the spike protein G (molecular weight 69,000). Analyses of the tryptic peptides showed that G1, G2, and G had identical peptide sequences.

Characterization and translation of methylated and unmethylated vesicular stomatitis virus mRNA synthesized in vitro by ribonucleoprotein particles from vesicular stomatitis virus-infected L cells.

Ribonucleoprotein particles isolated from extracts of vesicular stomatitis virus (VSV) -infected L cells synthesized in vitro four classes of polyadenylated RNA sedimenting at 29S, 19S, 17S, and 13S. When synthesized in vitro in the presence of the methyl donor S-adenosyl methionine, these RNA species contained the following 5'-terminal structures: (i) m7G5ppp5'AmpAp(70%) ; (ii) m7G5'ppp5'AmpAmpNp (20%) and (iii) pppAp (10%). In the presence of the methylation inhibitor S-adenosylhomocysteine, however, the mRNA contained the 5'-terminal structures G5'ppp5'Ap (80%) and pppAp (20%).