Characterization of 405B8H3(D-E), a newly engineered high affinity chimeric LAG-3 antibody with potent antitumor activity.

Lymphocyte activation gene-3 (LAG-3) is a type I transmembrane protein with structural similarities to CD4. Overexpression of LAG-3 enables cancer cells to escape immune surveillance, while its blockade reinvigorates exhausted T cells and strengthens anti-infection immunity. Blockade of LAG-3 may have antitumor effects.

Safety and efficacy of an anti-human APC antibody for prophylaxis of congenital factor deficiencies in preclinical models.

Rebalance of coagulation and anticoagulation to achieve a hemostatic effect has recently gained attention as an alternative therapeutic strategy for hemophilia. We engineered a humanized chimeric antibody, SR604, based on a previously published murine antibody, HAPC1573, which selectively blocks the anticoagulant activity of human activated protein C (APC). SR604 effectively blocked the anticoagulation activities of APC in human plasma deficient in various coagulation factors in vitro with affinities ∼60 times greater than that of HAPC1573.

Developing high-affinity decoy receptors to treat multiple myeloma and diffuse large B cell lymphoma.

Disease relapse and treatment-induced immunotoxicity pose significant clinical challenges for patients with hematological cancers. Here, we reveal distinctive requirements for neutralizing TNF receptor ligands APRIL and BAFF and their receptor activity in MM and DLBCL, impacting protein translation and production in MM cells and modulating the translation efficiency of the ATM interactor (ATMIN/ACSIZ). Therapeutically, we investigated the use of BCMA decoy receptor (sBCMA-Fc) as an inhibitor of APRIL and BAFF.

Neutralization of PD-L2 is Essential for Overcoming Immune Checkpoint Blockade Resistance in Ovarian Cancer.

Purpose: Ovarian cancer represents a major clinical hurdle for immune checkpoint blockade (ICB), with reported low patient response rates. We found that the immune checkpoint ligand PD-L2 is robustly expressed in patient samples of ovarian cancers and other malignancies exhibiting suboptimal response to ICB but not in cancers that are ICB sensitive. Therefore, we hypothesize that PD-L2 can facilitate immune escape from ICB through incomplete blockade of the PD-1 signaling pathway.

Study of the interactions of a novel monoclonal antibody, mAb059c, with the hPD-1 receptor.

Programmed cell death 1 (PD-1) monoclonal antibodies have been approved by regulatory agencies for the treatment of various types of cancer, and the mechanism involves the restoration of T cell functions. We report herein the X-ray crystal structure of a fully human monoclonal antibody mAb059c fragment antigen-binding (Fab) in complex with the PD-1 extracellular domain (ECD) at a resolution of 1.70 Å.

Ablation of calcineurin Aβ reveals hyperlipidemia and signaling cross-talks with phosphodiesterases.

Insulin resistance, hyperlipidemia, and cardiovascular complications are common dysregulations of metabolic syndrome. Transplant patients treated with immunosuppressant drugs such as cyclosporine A (CsA), an inhibitor of calcineurin phosphatase, frequently develop similar metabolic complications. Although calcineurin is known to mediate insulin sensitivity by regulating β-cell growth and adipokine gene transcription, its role in lipid homeostasis is poorly understood.

Elucidating protein: DNA complex by oligonucleotide DNA affinity purification.

Transcription factors recruit a wide variety of associated co-factors to regulate gene expression. These co-factors include protein kinases, phosphatases, deacetylases, methylases, and ubiquitin ligases, etc. To identify novel protein kinases associated with transcription factor NFAT, we took advantage of the increased ability of DNA binding and used an oligonucleotide affinity-binding approach.

CD40 pathway activation status predicts response to CD40 therapy in diffuse large B cell lymphoma.

The primary function of B cells, critical components of the adaptive immune response, is to produce antibodies against foreign antigens, as well as to perform isotype class switching, which changes the heavy chain of an antibody so that it can interact with different repertoires of effector cells. CD40 is a member of the tumor necrosis factor superfamily of cell surface receptors that transmits survival signals to B cells. In contrast, in B cell cancers, stimulation of CD40 signaling results in a heterogeneous response in which cells can sometimes undergo cell death in response to treatment, depending on the system studied.

Evolutionarily conserved role of calcineurin in phosphodegron-dependent degradation of phosphodiesterase 4D.

Calcineurin is a widely expressed and highly conserved Ser/Thr phosphatase. Calcineurin is inhibited by the immunosuppressant drug cyclosporine A (CsA) or tacrolimus (FK506). The critical role of CsA/FK506 as an immunosuppressant following transplantation surgery provides a strong incentive to understand the phosphatase calcineurin.

Integration of protein kinases mTOR and extracellular signal-regulated kinase 5 in regulating nucleocytoplasmic localization of NFATc4.

The target of rapamycin (TOR) signaling regulates the nucleocytoplasmic shuttling of transcription factors in yeast. Whether the mammalian counterpart of TOR (mTOR) also regulates nucleocytoplasmic shuttling is not known. Using a phospho-specific monoclonal antibody, we demonstrate that mTOR phosphorylates Ser(168,170) of endogenous NFATc4, which are conserved gate-keeping Ser residues that control NFAT subcellular distribution.

Regulation of transcription factor NFAT by ADP-ribosylation.

ADP-ribosylation is a reversible posttranslational modification mediated by poly-ADP-ribose polymerase (PARP). The results of recent studies demonstrate that ADP-ribosylation contributes to transcription regulation. Here, we report that transcription factor NFAT binds to and is ADP-ribosylated by PARP-1 in an activation-dependent manner.

Dosage-dependent transcriptional regulation by the calcineurin/NFAT signaling in developing myocardium transition.

Thin spongy myocardium is critical at early embryonic stage [before embryonic day (E) 13.5 in mice] to allow diffusion of oxygen and nutrients to the developing cardiomyocytes. However, establishment of compact myocardium at later stage ( approximately E16.

Role of transcription factor NFAT in glucose and insulin homeostasis.

Compromised immunoregulation contributes to obesity and complications in metabolic pathogenesis. Here, we demonstrate that the nuclear factor of activated T cell (NFAT) group of transcription factors contributes to glucose and insulin homeostasis. Expression of two members of the NFAT family (NFATc2 and NFATc4) is induced upon adipogenesis and in obese mice.

Role of the CCAAT/enhancer-binding protein NFATc2 transcription factor cascade in the induction of secretory phospholipase A2.

Inflammatory cytokines such as interleukin-1 and tumor necrosis factor-alpha modulate a transcription factor cascade in the liver to induce and sustain an acute and systemic defense against foreign entities. The transcription factors involved include NF-kappaB, STAT, and CCAAT/enhancer-binding protein (C/EBP). Whether the NFAT group of transcription factors (which was first characterized as playing an important role in cytokine gene expression in the adaptive response in immune cells) participates in the acute-phase response in hepatocytes is not known.

Recruitment of the extracellular signal-regulated kinase/ribosomal S6 kinase signaling pathway to the NFATc4 transcription activation complex.

Integration of protein kinases into transcription activation complexes influences the magnitude of gene expression. The nuclear factor of activated T cells (NFAT) group of proteins are critical transcription factors that direct gene expression in immune and nonimmune cells. A balance of phosphotransferase activity is necessary for optimal NFAT activation.

Requirement of transcription factor NFAT in developing atrial myocardium.

Nuclear factor of activated T cell (NFAT) is a ubiquitous regulator involved in multiple biological processes. Here, we demonstrate that NFAT is temporally required in the developing atrial myocardium between embryonic day 14 and P0 (birth). Inhibition of NFAT activity by conditional expression of dominant-negative NFAT causes thinning of the atrial myocardium.

Transcription cooperation by NFAT.C/EBP composite enhancer complex.

The nuclear factor of activated T cells (NFAT) group of transcription factors regulates gene expression in immune and non-immune cells. NFAT-mediated gene transcription is orchestrated, in part, by formation of a composite regulatory element. Here we demonstrate that NFAT interacts with transcription factor CCAAT/enhancer-binding protein (C/EBP) to form a composite enhancer complex, to potentiate expression of the peroxisome proliferator-activated receptor-gamma2 gene.

Phosphorylation of NFATc4 by p38 mitogen-activated protein kinases.

Nuclear factor of activated T cells (NFAT) is implicated in multiple biological processes, including cytokine gene expression, cardiac hypertrophy, and adipocyte differentiation. A conserved NFAT homology domain is identified in all NFAT members. Dephosphorylation of the NFAT homology region is critical for NFAT nuclear translocation and transcriptional activation.