16 results about "Negative selection" patented technology

Strategies, systems, methods, reagents, and kits for phage-assisted continuous evolution are provided herein. These include strategies, systems, methods, reagents, and kits allowing for stringency modulation to evolve weakly active or inactive biomolecule variants, negative selection of undesired properties, and / or positive selection of desired properties.

Disclosed herein are compositions comprising an oligonucleotide cathodic probe for purifying a cyclic nucleic acid wherein the cyclic nucleic acid is produced by self-splicing of a precursor nucleic acid comprising an oligonucleotide cathodic tag wherein the cathodic tag is at least 90% complementary to the cathodic probe, wherein the negative tag is removed during the self-splicing of the precursor nucleic acid, preferably the negative tag is complementary to the negative probe by at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99%, further preferably 100%. The invention also relates to a related purification method using the negative selection probe composition. The precursor nucleic acid at least comprises a 3'intron fragment, a target sequence, a translation enlightenment sequence and a 5 'intron fragment. Also disclosed herein are compositions for purifying a cyclic nucleic acid comprising an oligonucleotide positive selection probe, where the cyclic nucleic acid is produced by self-splicing of a precursor nucleic acid, where the positive selection probe is complementary to at least 60% of at least a portion of the cyclic nucleic acid produced by self-splicing of the precursor nucleic acid, and where the positive selection probe is not complementary to at least 60% of at least a portion of the cyclic nucleic acid produced by self-splicing of the precursor nucleic acid. At least a portion of the cyclic nucleic acid spans a splicing portion of the cyclic nucleic acid, the precursor nucleic acid does not have a sequence at least 60% complementary to the positive selection probe, and the precursor nucleic acid at least comprises a 3'intron fragment, a target sequence, a translation enlightenment sequence and a 5 'intron fragment.

Compositions and methods are provided for genetically modifying a T cell to express a chimeric antigen receptor (CAR) with knockout of an endogenous T cell receptor (TCR). The subject methods utilize a donor polynucleotide encoding a CAR that is integrated into an intron of a TCR gene. By knocking in a synthetic exon expressing the CAR into an intron, the successfully edited T cells produce a mature mRNA with a nucleotide sequence encoding the CAR spliced in between the exon(s) encoding the TCR protein, resulting in expression of the CAR and knockout of the TCR. In contrast, the unsuccessfully edited T cells retain expression of their TCR. The T cell population can be enriched for successfully edited TCR negative T cells expressing the CAR by using negative selection to remove unsuccessfully edited TCR positive T cells with binding agents that bind to the TCR marker.

The invention discloses a method for constructing a mouse model with a Cep295 gene knocked out in a cerebral cortex area, a targeting vector and a kit, the structure of the targeting vector sequentially comprises a 5'homologous arm from a 5'end to a 3 'end, the 5' homologous arm is derived from a genome sequence at the upstream of a No.11 exon of the mouse Cep295 gene, and the 5'homologous arm is derived from a genome sequence at the upstream of a No.11 exon of the mouse Cep295 gene; a flox region, wherein the flox region comprises exons from the 11th exon to the 15th exon of the mouse Cep295 gene; an Frt-pGK-Neo-polyA-Frt element, wherein the pGK-Neo-polyA is a selection marker gene expression cassette, and the Frt-pGK-Neo-polyA is an Frt-pGK-Neo-polyA-Frt element. The 3'homologous arm is derived from a genome sequence at the downstream of a No.15 exon of the mouse Cep295 gene; and an MC1-TK-polyA element, wherein the MC1-TK-polyA element is a negative selection marker gene expression cassette.

The invention discloses a cleaning robot autonomous path planning control method based on deep learning, and the method comprises the following steps: obtaining the pose and obstacle information of a cleaning robot, and generating a data packet containing obstacle distribution and blocked coordinates when detecting that a path is blocked; activating a reconnaissance granulocyte antibody family, generating a plurality of micro-paths constrained by curvature, evaluating the accessibility, and outputting safety direction information; encoding the path data and the safety direction to form an antigen vector, and generating a candidate antibody set; executing cloning, variation, concentration inhibition and negative selection according to the matching degree, and screening an optimal antibody path as a repair segment for output; and performing phagocytic recovery on the invalid antibody and updating variation prior, and performing closed-loop splicing on the repair path and the original path to generate an executable track. According to the invention, a reconnaissance granulocyte antibody family and a phagocytosis-recovery mechanism are introduced into an artificial immune algorithm, so that the path continuity and the operation stability in a complex environment are remarkably improved.

The present invention provides novel engineered polypeptides having structural and / or kinetic similarities to CD25 or a portion thereof, such as engineered polypeptides designed to mimic an epitope outside the IL-2 binding site. [Solution] Manipulated polypeptides comprising a combination of spatially related topological constraints in which at least one constraint originates from the CD25 reference target, and methods for selecting such manipulated polypeptides are provided herein. Further provided are methods for using manipulated polypeptides, including positive and / or negative selection molecules, in a method for screening a library of binding molecules such as antibodies. CD25 antibodies selected using these manipulated polypeptides are further provided herein.

Provided herein are methods for selectively depleting a target nucleic acid comprising a sequence that does not comprise a nucleotide variant of interest. In some embodiments, a concentration of the target nucleic acid comprising the variant sequence is increased relative to a concentration of the target nucleic acid comprising the wild-type sequence, a concentration of the target nucleic acid comprising a converted nucleotide is increased relative to a concentration of the target nucleic acid that does not comprise the converted nucleotide, or a concentration of the target nucleic acid that does not comprise the converted nucleotide is increased relative to a concentration of the target nucleic acid comprising the converted nucleotide. In some embodiments, the target nucleic acids are sequenced.

The invention discloses a primary endocardial endothelial cell extraction method suitable for cardiovascular disease research. Non-specific components are removed through directional sampling, enzyme digestion and mechanical dispersion of an endocardium microscopic spatula and in combination with a CD31 positive selection and CD36 negative selection combined strategy; after culture, Npr3 backtracking, functional verification and passage limitation (less than or equal to P2) are used for controlling quality. According to the method, the cells with the purity of 80-90%, the motility rate of more than or equal to 85% and stable Npr < 3 + > proportion can be obtained, and compared with a traditional method, the method has the advantages in the aspects of material taking specificity, function fidelity and repeatability. The invention provides a reliable cell source for cardiovascular disease research and transformation application.

The present invention is related to a nucleic acid molecule, which is also referred to as third nucleic acid molecule, wherein the third nucleic acid molecule comprises(1) a nucleic acid molecule comprising the following elements:(a) optionally, a first part of a genome of a virus;(b) a nucleotide sequence, preferably a genomic nucleotide sequence, or a transcription unit;(c) a regulatory nucleic acid sequence which has a regulatory activity in a prokaryote;(d) exactly one site-specific recombination site;(e) a nucleotide sequence providing for a negative selection marker;(f) a bacterial nucleotide sequence unit comprising (i) bacterial nucleotide sequences for conditional replication and (ii) a nucleotide sequence providing for a positive selection marker;(g) optionally a first restriction site; or(2) a nucleic acid molecule comprising a nucleotide sequence according to SEQ ID NO: 6; or(3) a nucleic acid molecule identical or similar to the nucleic acid molecule contained in the organism deposited with the DSMZ under the Budapest treaty under accession number DSM 23754, wherein preferably the nucleic acid molecule contained in the organism is a heterologous nucleic acid molecule;wherein the third nucleic acid molecule is either a linear or a circular molecule.

Methods for scarless genome editing are provided, particularly scarless genome modification by using a homology-directed repair (HDR) step to genetically modify a cell and remove an undesired sequence.SOLUTION: Provided is a method for scarless editing of genomic DNA of a cell comprising the following steps. The method comprises the steps of: (a) performing a first Cas9-mediated homologous recombination repair (HDR) step; (b) isolating genetically modified cells based on a positive selection of at least one selectable marker; (c) performing a second Cas9-mediated homologous recombination repair (HDR) step; and (d) isolating genetically modified cells containing the intended editing based on a negative selection of at least one selectable marker, wherein an expression cassette encoding the at least one selectable marker has been deleted.SELECTED DRAWING: Figure 1A

Provided herein engineered polypeptides that comprise a combination of spatially-associated topological constraints, wherein at least one constraint is derived from a CD25 reference target, and methods of selecting said engineered polypeptides. Further provided are methods of using the engineered polypeptides, including as positive and / or negative selection molecules in methods of screening a library of binding molecules such as antibodies. Further provided herein are CD25 antibodies selected using these engineered polypeptides.

Disclosed herein is a method of identifying an L-RNA aptamer specific for a target nucleic acid. According to some embodiments of the present disclosure, the method comprises, in vitro transcribing the DNAs of the DNA library into D-RNAs, followed by identifying target-specific D-RNAs via negative and positive selections, and then producing the L-RNA aptamer based on the identified D-RNA. Also disclosed herein are two aptamers identified by the present method. According to some embodiments of the present disclosure, the two aptamers respectively comprise the nucleotide sequences of SEQ ID NOs: 1 and 2.

Disclosed herein are compositions comprising an oligonucleotide cathodic probe for purifying a cyclic nucleic acid wherein the cyclic nucleic acid is produced by self-splicing of a precursor nucleic acid comprising an oligonucleotide cathodic tag wherein the cathodic tag is at least 90% complementary to the cathodic probe, wherein the negative tag is removed during the self-splicing of the precursor nucleic acid, preferably the negative tag is complementary to the negative probe by at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99%, further preferably 100%. The invention also relates to a related purification method using the negative selection probe composition.

The invention discloses a negative selection adaptive optimization method for unbalanced data resampling, and the method comprises the steps: constructing a parameter adaptive optimization model, and dynamically calculating and optimizing the radius r and neighborhood k value of a detector; an oversampling negative selection multi-point cross evolution model is constructed, and high-quality minority class samples are generated through a steady-state evolution strategy, multi-point cross evolution and negative selection; constructing an under-sampling negative selection optimization model, and adjusting the under-sampling negative selection optimization model through negative selection; through dynamic similarity measurement, a multi-point cross evolution dictionary, an information entropy weighted local outlier factor and differentiation feature weight calculation, a fitness evaluation function is guaranteed and designed through diversity tradeoff and convergence, parameter adaptive optimization is carried out, the quality of generated samples is improved, sample feature diversity is reserved, boundary confusion in a multi-label scene is eliminated, and the quality of the generated samples is improved. And the problems of information loss, overfitting and noise amplification of a resampling method can be solved.

The present invention provides a novel donor polynucleotide in which both ends of a genomic fragment containing a cleavable site are ligated by a polynucleotide containing a positive selection marker gene and a negative selection marker gene. By using this donor polynucleotide, cleavage can be performed at a homologous site of the donor polynucleotide without cleavage within the target locus, thereby avoiding the possibility of introducing mutations other than the target sequence, which is called Off-target, and enabling modification of only the target gene.