Yin Chen

US Patent:

7419964, Sep 2, 2008

Filed:

Dec 6, 2002

Appl. No.:

10/313828

Inventors:

Yin Chen - Pearland TX, US
Malcolm Skolnick - Houston TX, US

Assignee:

Cytogenix, inc. - Houston TX

International Classification:

A01N 43/04
C12Q 1/68
C12N 15/00
C07H 21/02
C07H 21/04

US Classification:

514 44, 435 6, 435 911, 4353201, 435455, 514 1, 536 231

Abstract:

A composition for treatment of HSV-related pathologies including an expression vector for altering expression of a target sequence in an HSV-infected cell by production of single-stranded cDNA (ssDNA) in the cell in vivo suspended for topical application to an affected site in a suitable delivery vehicle. The expression vector is comprised of a cassette comprising a sequence of interest, an inverted tandem repeat, and a primer binding site 3′ to the inverted tandem repeat, and a reverse transcriptase/RNAse H coding gene, and is transfected into the infected cells for inhibition of HSV replication. The resulting ssDNA binds to the target sequence to alter expression of the target sequence for such purposes as gene activation or inactivation using duplex or triplex binding of nucleic acids, site-directed mutagenesis, interruption of cellular function by binding to specific cellular proteins, or interfering with RNA splicing functions.

US Patent:

20030082800, May 1, 2003

Filed:

May 1, 2002

Appl. No.:

10/136218

Inventors:

Charles Conrad - Houston TX, US
Yin Chen - Pearland TX, US

Assignee:

CytoGenix, Inc. - Houston TX

International Classification:

C12N015/00
C12N005/06

US Classification:

435/325000, 435/320100

Abstract:

An expression vector for altering expression of a target nucleic acid sequence in a host cell by production of single-stranded cDNA (ssDNA) in the host cell in vivo. The expression vector is comprised of a cassette comprising a sequence of interest, an inverted tandem repeat, and a primer binding site 3′ to the inverted tandem repeat, and a reverse transcriptase/RNAse H coding gene, and may be transfected into the host cell. Transcription of the cassette by the host cell produces an RNA template which is reverse transcribed with the product of the RT coding gene to produce ssDNA of a specified sequence. The ssDNA is modified to remove flanking vector sequences by taking advantage of the “stem-loop” structure of the ssDNA, which forms as a result of the inverted tandem repeat that allows the ssDNA to fold back on itself, forming a double stranded DNA stem. The double-stranded stem may contain one or more restriction endonuclease recognition sites and the loop, which remains as ssDNA, can be any desired nucleotide sequence. This design allows the double-stranded stem of the stem-loop intermediate to be cleaved by the desired corresponding restriction endonuclease(s) and the loop portion is then released as a linearized, single-stranded piece of DNA. The resulting ssDNA binds to an endogenous target nucleic acid sequence to alter the expression of that sequence for such therapeutic purposes as gene activation or inactivation using duplex or triplex binding of nucleic acids, site-directed mutagenesis, interruption of cellular function by binding to specific cellular proteins, or interfering with RNA splicing functions.

US Patent:

20040248101, Dec 9, 2004

Filed:

Jun 3, 2003

Appl. No.:

10/453410

Inventors:

Yin Chen - Pearland TX, US
Xin Tan - Manvel TX, US

Assignee:

CytoGenix, Inc. - Houston TX

International Classification:

C12Q001/68
C07H021/04
C12N015/74
C12N001/21

US Classification:

435/006000, 536/023100, 435/472000, 435/252300

Abstract:

A selectively inducible, single-stranded DNA (ssDNA) expression library, a method for constructing a ssDNA expression library, a method for screening ssDNA using the expression library, and a method for identifying ssDNA molecules that switch on or off bacterial gene(s) related to cell growth and toxin production and secretion. The screening library is used to, among other things, identify ODNs effective in stopping bacterial growth, killing bacteria or preventing bacteria from synthesizing and secreting their toxins is the focus of the present invention and/or to discover ODNs effective in eukaryotic (e.g., mammalian) cells for targeted gene down regulation. The library is also useful for identifying ssDNAs or ODNs that are used as therapeutic antibacterial reagents, for identifying essential bacterial genes that can serve as targets for antibiotic discovery, and for providing a method for treatment of bacterial infections.

US Patent:

20050020526, Jan 27, 2005

Filed:

Apr 5, 2004

Appl. No.:

10/818158

Inventors:

Yin Chen - Pearland TX, US
Xin Tan - Manvel TX, US

Assignee:

CytoGenix, Inc. - Houston TX

International Classification:

A61K048/00
C12N015/74
C12N005/08

US Classification:

514044000, 435366000, 435320100

Abstract:

A method for producing ODNs in bacterial or fungal cells in vivo for treatment of sepsis so that, when the ODNs reach and knock down their target genes, and thereby kill bacterial or fungal cells or inhibit their growth, the bacterial or fungal accumulation in the bloodstream is held constant or diminished and the sepsis syndrome is reduced or eliminated. The invention also contemplates of certain ODNs for use in treatment of sepsis.

US Patent:

20050136393, Jun 23, 2005

Filed:

Dec 23, 2003

Appl. No.:

10/743956

Inventors:

Yin Chen - Pearland TX, US
Xin Tan - Manvel TX, US

Assignee:

CytoGenix, Inc. - Houston TX

International Classification:

C12Q001/00
C12Q001/68
C12N009/22
C12N015/85

US Classification:

435004000, 435455000, 435199000, 435325000

Abstract:

A selectively inducible, single-stranded DNA (ssDNA) expression library, a method for constructing a ssDNA expression library, a method for screening ssDNA using the expression library, and a method for identifying ssDNA molecules that alter expression of bacterial gene(s) related to cell growth and toxin production and secretion. The screening library is used to, among other things, identify ODNs effective in stopping bacterial growth, killing bacteria or preventing bacteria from synthesizing and secreting their toxins, and/or to discover ODNs effective in eukaryotic (e.g., mammalian) cells for targeted alteration of gene function. The library is also useful for identifying ssDNAs or ODNs that are used as therapeutic antibacterial reagents, for identifying essential bacterial genes that can serve as targets for antibiotic discovery, and for providing a method for treatment of bacterial infections.

US Patent:

20050260588, Nov 24, 2005

Filed:

May 1, 2003

Appl. No.:

10/513191

Inventors:

Charles Conrad - Houston TX, US
Yin Chen - Pearland TX, US

International Classification:

C12Q001/68
C12P021/06
C12N015/74

US Classification:

435006000, 435069100, 435320100, 435325000

Abstract:

An expression vector for altering expression of a target nucleic acid sequence in a host cell by production of single-stranded cDNA (ssDNA) in the host cell in vivo. The expression vector is comprised of a cassette comprising a sequence of interest, an inverted tandem repeat, and a primer binding site 3′ to the inverted tandem repeat, and a reverse transcriptase/RNAse H coding gene, and may be transfected into the host cell. Transcription of the cassette by the host cell produces an RNA template which is reverse transcribed with the product of the RT coding gene to produce ssDNA of a specified sequence. The ssDNA is modified to remove flanking vector sequences by taking advantage of the “stem-loop” structure of the ssDNA, which forms as a result of the inverted tandem repeat that allows the ssDNA to fold back on itself, forming a double stranded DNA stem. The double-stranded stem may contain one or more restriction endonuclease recognition sites and the loop, which remains as ssDNA, can be any desired nucleotide sequence. This design allows the double-stranded stem of the stem-loop intermediate to be cleaved by the desired corresponding restriction endonuclease(s) and the loop portion is then released as a linearized, single-stranded piece of DNA. The resulting ssDNA binds to an endogenous target nucleic acid sequence to alter the expression of that sequence for such therapeutic purposes as gene activation or inactivation using duplex or triplex binding of nucleic acids, site-directed mutagenesis, interruption of cellular function by binding to specific cellular proteins, or interfering with RNA splicing functions.

US Patent:

20070020635, Jan 25, 2007

Filed:

Jun 3, 2004

Appl. No.:

10/574254

Inventors:

Yin Chen - Pearland TX, US
Xin Tan - Manvel TX, US

Assignee:

CytoGenix, Inc. - Houston TX

International Classification:

C12Q 1/68
C40B 40/02
C40B 40/08
C07H 21/04
A61K 48/00
C12N 15/74

US Classification:

435006000, 435471000, 435483000, 435252300, 435254200, 536023700, 514044000

Abstract:

A selectively inducible, single-stranded DNA (ssDNA) expression library, a method for constructing a ssDNA expression library, a method for screening ssDNA using the expression library, and a method for identifying ssDNA molecules that alter expression of bacterial and fungal gene(s) related to cell growth and toxin production and secretion. The screening library is used to, among other things, identify ODNs effective in stopping cell growth, killing bacteria or fungi, or preventing bacteria and/or fungi from synthesizing and secreting their toxins, and/or to discover ODNs effective in eukaryotic (e.g., mammalian) cells for targeted alteration of gene function. The library is also useful for identifying ssDNAs or ODNs that are used as therapeutic agents for, for instance, providing a method for treatment of bacterial infections such as sepsis.

US Patent:

20080206154, Aug 28, 2008

Filed:

Sep 28, 2005

Appl. No.:

11/664052

Inventors:

Yin Chen - Pearland TX, US
Xin Xing Tan - Manvel TX, US

Assignee:

CytoGenix, Inc. - Houston TX

International Classification:

A61K 31/713
C07H 21/02
C12N 15/66
A61P 31/00
C07H 21/04
C12N 5/00

US Classification:

424 44, 536 231, 4353201, 435325, 536 237

Abstract:

The current invention is directed to oligonucleotide sequences isolated from a sequence designated rbl-1 [SEQ ID NO. 19] that either kill or inhibit growth, or prevent the production of endogenously expressed toxin, of microorganisms. These ssDNA sequences, identified through use of a screening method, appear to act as modulators of essential growth functions which may act at the level of triplex formation, antisense inhibition, or as aptamers that alter gene function. The sequences, referred to as minimum functional regions, or MFRs, are useful inter alia as therapeutic agents for treatment of sepsis and other pathologies caused by microorganisms such as sepsis and/or in which microorganisms are contributory agents.