ABSTRACT
The 26th Antibody Engineering & Therapeutics meeting, the annual meeting of The Antibody Society united over 800 participants from all over the world in San Diego from 6-10 December 2015. The latest innovations and advances in antibody research and development were discussed, covering a myriad of antibody-related topics by more than 100 speakers, who were carefully selected by The Antibody Society. As a prelude, attendees could join the pre-conference training course focusing, among others, on the engineering and enhancement of antibodies and antibody-like scaffolds, bispecific antibody engineering and adaptation to generate chimeric antigen receptor constructs. The main event covered 4 d of scientific sessions that included antibody effector functions, reproducibility of research and diagnostic antibodies, new developments in antibody-drug conjugates (ADCs), preclinical and clinical ADC data, new technologies and applications for bispecific antibodies, antibody therapeutics for non-cancer and orphan indications, antibodies to harness the cellular immune system, building comprehensive IgVH-gene repertoires through discovering, confirming and cataloging new germline IgVH genes, and overcoming resistance to clinical immunotherapy. The Antibody Society's special session focused on "Antibodies to watch" in 2016. Another special session put the spotlight on the limitations of the new definitions for the assignment of antibody international nonproprietary names introduced by the World Health Organization. The convention concluded with workshops on computational antibody design and on the promise and challenges of using next-generation sequencing for antibody discovery and engineering from synthetic and in vivo libraries.
Subject(s)
Antibodies, Monoclonal , Immunoconjugates , Protein Engineering , Societies, Scientific , Animals , California , Congresses as Topic , HumansABSTRACT
Zinc-finger protein transcription factors (ZFP TFs) can be designed to control the expression of any desired target gene, and thus provide potential therapeutic tools for the study and treatment of disease. Here we report that a ZFP TF can repress target gene expression with single-gene specificity within the human genome. A ZFP TF repressor that binds an 18-bp recognition sequence within the promoter of the endogenous CHK2 gene gives a >10-fold reduction in CHK2 mRNA and protein. This level of repression was sufficient to generate a functional phenotype, as demonstrated by the loss of DNA damage-induced CHK2-dependent p53 phosphorylation. We determined the specificity of repression by using DNA microarrays and found that the ZFP TF repressed a single gene (CHK2) within the monitored genome in two different cell types. These data demonstrate the utility of ZFP TFs as precise tools for target validation, and highlight their potential as clinical therapeutics.
Subject(s)
Gene Expression Regulation , Protein Kinases/genetics , Protein Serine-Threonine Kinases , Transcription Factors/genetics , Transcription Factors/metabolism , Zinc Fingers/genetics , Base Sequence , Binding Sites/genetics , Cell Line , Checkpoint Kinase 2 , DNA/genetics , DNA/metabolism , DNA Damage , Gene Expression Regulation, Enzymologic , Genome, Human , Humans , Promoter Regions, Genetic , Protein Engineering , Protein Kinases/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Repressor Proteins/genetics , Repressor Proteins/metabolismABSTRACT
The artificial regulation of endogenous gene expression in plants is limited to only a few approaches. Here, we describe the use of artificial zinc finger chimeras to regulate the expression of a known reporter construct. The artificial zinc finger chimera TFIIIAZif is a fusion protein consisting of the four zinc fingers of TFIIIA linked through a spacer region to the three zinc fingers of Zif268. This artificial zinc finger chimera is able to bind specifically to a target DNA sequence (ZBS, zinc finger binding site) of 27 base pairs (bp). TFIIIAZif was fused to a transactivation domain from the herpes simplex virus VP16 or its tetramer VP64 to give ZF-VP16 or ZF-VP64, respectively. In transient expression assays, these two transcription activators were able to activate a target reporter gene (luc and GFP) expressed from a minimal -46 35S promoter linked to four copies of ZBS. The activation was confirmed in transgenic plants using an inducible XVE system [Zuo et al. (2000) Plant J. 24: 265] to express ZF-VP16 or ZF-VP64. Furthermore, to test the specificity of ZF-VP64 we have compared reporter gene expression from a wild type (1xZBS) and a mutant (1xZBSmu) binding site in transgenic plants. The 1xZBS was used to express green fluorescent protein (GFP) whereas the 1xZBSmu was used to express red fluorescent protein (RFP). Upon induction of ZF-VP64 we found a much higher expression of GFP (about 33-fold) as compared to RFP expression. These results suggest that artificial zinc finger chimeras can be used to target specific DNA sequences and to regulate gene expression in plants.
