The present invention provides new stable packaging cell lines and producer cell lines as well as methods to obtain them, and a new method to produce lentiviral vectors using such cell lines. New methods and packaging cell lines of the invention are generated using a baculo-AAV hybrid system for stable expression of structural and regulatory lentiviral proteins, such system comprising a baculoviral backbone containing an integration cassette flanked by AAV ITR, in combination with a plasmid encoding rep protein. This system allows to obtain a stable integration of the structural and regulatory HIV-1 proteins gag/pol and rev. The system allows to obtain a first intermediate including only the structural and regulatory HIV proteins gag/pol and rev, to be used as starting point to obtain stable packaging cell lines as well as producer cell lines.

Methods and constructs for engineering circular RNA are disclosed. In some embodiments, the methods and constructs comprise a vector for making circular RNA, the vector comprising the following elements operably connected to each other and arranged in the following sequence: a.) a 5′ homology arm, b.) a 3′ group I intron fragment containing a 3′ splice site dinucleotide, c.) optionally, a 5′ spacer sequence, d.) a protein coding or noncoding region, e.) optionally, a 3′ spacer sequence, f) a 5′ Group I intron fragment containing a 5′ splice site dinucleotide, and g.) a 3′ homology arm, the vector allowing production of a circular RNA that is translatable or biologically active inside eukaryotic cells. Methods for purifying the circular RNA produced by the vector and the use of nucleoside modifications in circular RNA produced by the vector are also disclosed.

Provided herein is a baculovirus expression vector system for the production of a desired protein. In one aspect, the desired protein is a closed-ended DNA (ceDNA) molecule comprising wild-type and/or truncated inverted terminal repeats derived from a genome of a member of the viral family Parvoviridae.

The present invention relates nucleic acid constructs for the production of recombinant parvoviral (e.g. adeno-associated viral) vectors in insect cells, to insect cells comprising such constructs and to methods wherein the cells are used to produce recombinant parvoviral virions. The insect cells preferably comprise a first nucleotide sequence encoding the parvoviral rep proteins whereby the initiation codon for translation of the parvoviral Rep78 protein is a suboptimal initiation codon that effects partial exon skipping upon expression in insect cells. The insect cell further comprises a second nucleotide sequence comprising at least one parvoviral (AA V) inverted terminal repeat (ITR) nucleotide sequence and a third nucleotide sequence comprising a sequences coding for the parvoviral capsid proteins.

The present disclosure provides nucleic acid molecules comprising a first inverted terminal repeat (ITR), a second ITR, and a genetic cassette encoding a target sequence. In some embodiments, the first ITR and/or the second ITR is an ITR of human bocavirus. Also disclosed are methods of using the nucleic acid molecules in gene therapy applications.

The present disclosure belongs to the technical field of bio-medicine, particularly, the present disclosure relates to a tissue-specifically expressed circular RNA molecule, a cyclization precursor RNA molecule, a recombinant nucleic acid molecule, a recombinant expression vector, a recombinant host cell, a composition, a pharmaceutical preparation and application thereof in preparation of a drug for preventing or treating diseases, as well as a method for preventing or treating diseases. The circular RNA molecule provided by the present disclosure operably links a coding region to an expression regulatory element, realizing specific high expression of a target polypeptide in target cells or target tissues, and low expression of the target polypeptide in non-target cells or non-target tissues, and having high tissue expression specificity, thereby providing a safe and effective treatment strategy for clinical targeted therapy of diseases such as tumors.

Provided herein are compositions that include at least two different nucleic acid vectors, where each of the at least two different vectors includes a coding sequence that encodes a different portion of an otoferlin protein, and the use of these compositions to treat hearing loss in a subject.

An expression system for expressing a herpesvirus glycoprotein complex including a vector inserted with two or more nucleic acid sequences that encode two or more subunits of a herpesvirus glycoprotein complex linked by one or more linking sequences such that the subunits are co-expressed simultaneously and self-processed to assemble into a glycoprotein complex. The expression system or the vector can be included in a vaccine composition. The vaccine composition can be used for preventing or treating herpesvirus infections.

A circular mRNA molecule possessing features resembling native mammalian mRNA demonstrates improved translation, while retaining the properties of an extremely long half-life inside cells. This circular mRNA is functional inside mammalian cells, being able to compete against native cellular mRNAs for the eukaryotic translation initiation machinery. The invention possesses additional RNA elements compared to a previous invention containing only an IRES element for successful in vitro or in vivo translation.

A vector production system is provided. The system comprises recombinant cells designed to encode at least a first recombinase under the control of an inducible promoter and the cells include an expression vector encoding a nucleic acid of interest within the regulatory elements of the expression vector which are flanked on either side by a target sequence for at least the first recombinase. The vector production system provides an efficient one-step process for producing linear or circular covalently closed vectors that incorporate a nucleic acid sequence of interest.