Patents by Inventor Clas Kallander

Clas Kallander has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20040170958
    Abstract: A method of testing phenotypic drug susceptibility in an enveloped virus-infected mammalian individual by testing on an enzyme packed into an enveloped virus, such as HIV, recovered from a biological sample, such as blood or plasma, from said individual is described. The method comprises the steps of a) adding an enzyme inactivating agent to the sample for inactivating polymerase activity other than that present in the enveloped virion, b) removing the enzyme inactivating agent, enzyme activity blocking antibodies, endogenous enzyme activity inhibitors and antiviral drugs, c) lysing the virus particle to release the enzyme, d) recovering the concentrated purified viral enzyme, such as a HIV reverse transcriptase (RT), resulting from c) and determining the drug sensitivity profile of the individual from the recovered enzyme by using sensitive enzyme assays. The drug sensitivity profile may be used for selecting drug treatment therapy. A commercial package is included.
    Type: Application
    Filed: December 10, 2003
    Publication date: September 2, 2004
    Inventors: Clas Kallander, Anders Malmsten, Simon Gronowitz, Xingwu Shao
  • Publication number: 20040157230
    Abstract: A method for measuring DNA-dependent DNA polymerisation in a biological sample, is described. The method comprises the steps of providing a primer with a single stranded short specific sequence, which is unable to base pair internally, bound to a solid phase; contacting the primer construct with a reaction mixture containing a single stranded deoxynucleotide template with a part of the sequence complementary to the primer and the four deoxynucleoside triphosphates, one of which is modified so that it is specifically recognized by a labeled antibody; adding a biological sample comprising the DNA polymerase, such as retrovirus reverse transcriptase (RT), to the mixture; allowing the polymerase reaction to proceed; incubating the immobilized reaction product with the labeled antibody; detecting the amount of bound labeled antibody; and measuring the amount of incorporated modified deoxynucleoside triphosphate, as a measure of the DNA polymerisation, which may be used drug susceptibility testing.
    Type: Application
    Filed: December 10, 2003
    Publication date: August 12, 2004
    Inventors: Clas Kallander, Ingvar Petterson, Simon Gronowitz, Xingwu Shao
  • Publication number: 20040110265
    Abstract: A method of recovering an enzyme activity, such as reverse transcriptase (RT) activity, from enveloped viruses, such as HIV, in a biological sample containing a non-protected enzymes, is described. A cysteine-modifying substance is used to destroy the activity of the non-protected enzymes, followed by removal of the enveloped virus particles or inactivation of the cysteine-modifying substance with a chemical. Then the virus envelope is lysed and the released enzymes are recovered. Commercial packages containing written and/or data carrier instructions and some chemicals for performing laboratory steps for recovery of an enzyme activity from enveloped viruses, are also disclosed.
    Type: Application
    Filed: October 3, 2003
    Publication date: June 10, 2004
    Inventors: Clas Kallander, Simon Gronowitz, Tommy Gatu
  • Publication number: 20030104441
    Abstract: A method of concentrating and recovering an enzyme activity from enveloped viruses present in a biological sample, is described. The method comprises contacting the biological sample in a first buffer solution with a virus-binding matrix, such as an anion exchanger matrix, to attach virus particles present in the sample to the matrix, washing the matrix carrying the virus particles with a second buffer solution to remove components interfering with viral enzyme activity, lysing the immobilized virus particles in a third buffer solution and recovering the concentrated viral enzyme activity from the third buffer solution. Additionally, a commercial package containing written and/or data carrier instructions for performing laboratory steps for concentration and recovery of an enzyme activity from enveloped viruses present in a biological sample and at least one component necessary for the assay, is disclosed.
    Type: Application
    Filed: September 25, 2002
    Publication date: June 5, 2003
    Inventors: Anders Malmsten, Ingvar Pettersson, Tommy Gatu, Clas Kallander, Simon Gronowitz
  • Patent number: 6132995
    Abstract: A method for determining the activity of a nucleotide polymerizing enzyme in a sample, and use of the method for determining HIV 1 RT- and Herpes Simplex DNA-polymerase activity. The enzyme is captured by means of a nonoclonal antibody which is immobilized to a solid carrier and is capable of binding the enzyme without detrimentally effecting the enzyme activity. Contaminants and disturbing factors are removed and the nucleotide polymerization starts by the addition of a reaction solution containing a primer/template construct and nucleotides substrate, the reaction conditions being chosen such that they promote permanent association between antibody enzyme- and primer/template constructs. When necessary a nucleotide substrate, primer/template and reaction solution are washed away from the newly synthesized polymer, and the amount of nucleotide which as been incorporated into the polymer is determined, and the activity of the enzyme is determined with the guidance of this determination.
    Type: Grant
    Filed: April 13, 1998
    Date of Patent: October 17, 2000
    Assignee: Cavidi Tech AB
    Inventors: Jan-Simon Gronowitz, Clas Kallander, Johan Lennerstrand