The invention provides compositions and methods for reprogramming minimal volumes of mononuclear cells. In particular aspects, the invention provides methods and compositions for reprogramming minimal volumes of umbilical cord blood obtained from cord blood segments from cryopreserved cord blood segments.

An integration-defective retroviral vector transfer cassette lacking a functional polypurine tract (PPT) is provided. Also provided are isolated nucleic acids that include a heterologous nucleotide sequence, one or two retroviral long terminal repeats (LTRs), a packaging signal, a rev responsive element, and a eukaryotic promoter, wherein the nucleic acid lacks a functional PPT; vectors that include the disclosed isolated nucleic acids; recombinant retroviral particles and mRNAs thereof; retroviral vector kits; and methods for producing integration-defective vector particles, achieving gene expression of a nucleotide sequence of interest, and inserting a nucleotide sequence of interest into a host cell genome in a site-specific or non-specific manner.

The present invention relates generally to synthetic genes for modifying endogenous gene expression in a cell, tissue or organ of a transgenic organism, in particular a transgenic animal or plant. More particularly, the present invention provides novel synthetic genes and genetic constructs which are capable of repressing delaying or otherwise reducing the expression of an endogenous gene or a target gene in an organism when introduced thereto.

The present invention relates generally to a method of modifying gene expression and to synthetic genes for modifying endogenous gene expression in a cell, tissue or organ of a transgenic organism, in particular a transgenic animal or plant. More particularly, the present invention utilizes recombinant DNA technology to post-transcriptionally modify or modulate the expression of a target gene in a cell, tissue organ or whole organism, thereby producing novel phenotypes. Novel synthetic genes and genetic constructs which are capable of repressing delaying or otherwise reducing the expression of an endogenous gene or target gene in an organism when introduced thereto are also provided.

An integration-defective retroviral vector transfer cassette lacking a functional polypurine tract (PPT) is provided. Also provided are isolated nucleic acids that include a heterologous nucleotide sequence, one or two retroviral long terminal repeats (LTRs), a packaging signal, a rev responsive element, and a eukaryotic promoter, wherein the nucleic acid lacks a functional PPT; vectors that include the disclosed isolated nucleic acids;

recombinant retroviral particles and mRNAs thereof; retroviral vector kits; and methods for producing integration-defective vector particles, achieving gene expression of a nucleotide sequence of interest, and inserting a nucleotide sequence of interest into a host cell genome in a site-specific or non-specific manner.

The present invention provides HIV-derived lentivectors which are safe, highly efficient, and very potent for expressing transgenes for human gene therapy, especially, in human hematopoietic progenitor cells as well as in all other blood cell derivatives. The lentiviral vectors comprise a self-inactivating configuration for biosafety and promoters such as the EF1 promoter as one example. Additional promoters are also described. The vectors can also comprise additional transcription enhancing elements such as the wood chuck hepatitis virus post-transcriptional regulatory element. These vectors therefore provide useful tools for genetic treatments such as inherited and acquired lympho-hematological disorders, gene-therapies for cancers especially the hematological cancers, as well as for the study of hematopoiesis via lentivector-mediated modification of human HSCs.

The present invention relates to a polynucleotide comprising at least one promoter and an S/MAR element, wherein the S/MAR element is located downstream of the promoter in the 3 UTR of the transcription unit and wherein the S/MAR element is flanked by a 5 splice donor site and a 3 splice acceptor site; the present invention further relates to a composition comprising the polynucleotide, and to the polynucleotide for use in medicine and for use in treating genetic disease.

A eukaryotic expression vector capable of displaying a multi-chain polypeptide on the surface of a host cell is provided, such that the biological activity of the multi-chain polypeptide is exhibited at the surface of the host cell. Such a vector allows for the display of complex biologically active polypeptides, e.g., biologically active multi-chain polypeptides such as immunoglobulin Fab fragments. The present invention describes and enables the successful display of a multi-chain polypeptide on the surface of a eukaryotic host cell. Preferred vectors are described for expressing the chains of a multi-chain polypeptide in a host cell separately and independently (e.g., under separate vector control elements, and/or on separate expression vectors, thus forming a matched vector set). The use of such matched vector sets provides flexibility and versatility in the generation of eukaryotic display libraries, for example the ability to generate and to display multi-chain polypeptides by combining and recombining vectors that express variegations of the individual chains of a multi-chain polypeptide. Entire repertoires of novel chain combinations can be devised using such vector sets.

Disclosed is a method that includes: (i) providing a plurality of initial nucleic acid cassettes that include: a) a first coding region encoding a first immunoglobulin variable domain, b) a second coding region encoding a second immunoglobulin variable domain, and c) a ribosomal binding site disposed between the first and second coding regions for translation of the second polypeptide in a first expression system, wherein the first and second coding regions are in the same translational orientation; (ii) modifying each nucleic acid cassette of the plurality in a single reaction mixture so that it is functional in a second expression system, wherein the first and second region remain physically attached during the modifying; (iii) introducing each modified nucleic acid cassette into a mammalian cell to produce a mixture of transfected cells; and (iv) expressing each modified nucleic acid cassette in the transfected cells.

Methods and composition of induction of pluripotent stem cells and other desired cell types are disclosed. For example, in certain aspects methods for generating essentially vector-free induced pluripotent stem cells are described. Furthermore, the invention provides induced pluripotent stem cells and desired cell types essentially free of exogenous vector elements with the episomal expression vectors to express differentiation programming factors.