Both IL-2 and IL-4 bind to receptors containing the common γ chain and JAK3. Although JAK3 is required for proper lymphoid development, the precise roles of this kinase in IL-2 and IL-4 signaling in ...lymphocytes have not been defined. Here, we have studied IL-2 and IL-4 signaling in B cell lines lacking JAK3. Although IL-2-induced phosphorylation of IL-2Rβ, JAK1, and STAT5 all required the presence of JAK3, IL-4-mediated phosphorylation of JAK1, STAT6, and insulin receptor substrates 1 and 2 did not. However, IL-4-induced effects were clearly improved following JAK3 expression. These data indicate that IL-4 signaling occurs in the absence of of JAK3, but is comparatively inefficient. These findings may help in understanding the pathogenesis of the immunodeficiency that occurs with mutations of JAK3 and may suggest a mechanism for the pleiotropic effects of IL-4.
In addition to the therapeutic applicability of targeted protein degradation (TPD), the modality also harbors unique properties that enable the development of innovative chemical biology tools to ...interrogate complex biology. TPD offers an all-chemical strategy capable of the potent, durable, selective, reversible, and time-resolved control of the levels of a given target protein in both in vitro and in vivo contexts. These properties are particularly well-suited for enabling the precise perturbation of a given gene to understand its biology, identify dependencies/vulnerabilities in disease contexts, and as a strategy to control gene therapies. To leverage these elegant properties, we developed the AchillesTag (aTAG) degradation system to serve as a tool in target identification and validation efforts. The aTAG degradation system provides a novel degradation tag based on the MTH1 protein paired with three fully validated bifunctional degraders with both in vitro and in vivo applicability. We catalog the development of the aTAG system from selection and validation of the novel MTH1 aTAG, alongside a comprehensive SAR campaign to identify high performing tool degraders. To demonstrate the utility of the aTAG system to dissect a complex biological system, we apply the technology to the control of Chimeric Antigen Receptor (CAR) activity. Using aTAG, we demonstrate the ability to potently and selectively control CAR protein levels, resulting in the exquisite rheostat control of CAR mediated T-cell activity. Furthermore, we showcase the in vivo application of the system via degradation of the aTAG-fused CAR protein in a human xenograft model. The aTAG degradation system provides a complete chemical biology tool to aid foundational target validation efforts that inspire drug discovery campaigns towards therapeutic applicability.
Interleukin-4 (IL-4) is an important cytokine for B and T lymphocyte function and mediates its effects via a receptor that contains γc. B cells derived from patients with X-linked severe combined ...immunodeficiency (X-SCID) are deficient in γc and provide a useful model in which to dissect the role of this subunit in IL-4-mediated signaling. We found that although IL-4 stimulation of X-SCID B cells did not result in Janus tyrosine kinase-3 (JAK3) phosphorylation, other IL-4 substrates including JAK1 and IRS-1 were phosphorylated. Additionally, we detected signal transducers and activators of transcription 6 (STAT6) tyrosine phosphorylation and DNA binding activity in X-SCID B cells with a wide range of γc mutations. However, reconstitution of these X-SCID B cells with γc enhanced IL-4-mediated responses including STAT6 phosphorylation and DNA binding activity and resulted in increased CD23 expression. Thus, γc is not necessary to trigger IL-4-mediated responses in B cells, but its presence is important for optimal IL-4-signaling. These results suggest that two distinct IL-4 signaling pathways exist.
Despite technical advances, the ability to restore motor function following a brachial plexus avulsion is limited. Twenty patients who suffered the loss of elbow flexion following a brachial plexus ...avulsion injury underwent a neurotization procedure in an attempt to restore that lost function. Of 16 patients who underwent intercostal to musculocutaneous nerve anastomosis, seven obtained good elbow flexion. Four patients who no longer had a viable biceps brachialis muscle underwent an anastomosis between transposed intercostal nerves and a free vascularized gracilis muscle grafted to the position of the biceps. Two of these patients obtained good elbow flexion. Although synkinesis between the biceps brachialis and the inspiratory muscles can be demonstrated during coughing and deep inspiration, the patients learn to flex their reinnervated biceps brachialis muscle and maintain flexion independent of respiration.
Mutations affecting the expression of the Janus family kinase JAK3 were recently shown to be responsible for autosomal recessive severe combined immunodeficiency (SCID). JAK3-deficient patients ...present with a clinical phenotype virtually indistinguishable from boys affected by X-linked SCID, a disease caused by genetic defects of the common gamma chain (gamma c) that is a shared component of the receptors for IL-2, IL-4, IL-7, IL-9, and IL-15. The specific interaction of JAK3 and gamma c represents the biochemical basis for the similarities between these two immunodeficiencies. Both forms of SCID are characterized by recurrent, severe infections leading to death in infancy unless successfully treated by allogeneic bone marrow transplantation. Because of the potentially lethal complications associated with allogeneic bone marrow transplantation and the frequent lack of suitable marrow donors, the development of alternative forms of therapy is highly desirable. To this end, we investigated a retroviral-mediated gene correction approach for JAK3-deficiency. A vector carrying a copy of JAK3 cDNA was constructed and used to transduce B cell lines derived from patients with JAK3-deficient SCID. We demonstrate restoration of JAK3 expression and phosphorylation upon IL-2 and IL-4 stimulation. Furthermore, patients' cells transduced with JAK3 acquired the ability to proliferate normally in response to IL-2. These data indicate that the biological defects of JAK3-deficient cells can be efficiently corrected in vitro by retroviral-mediated gene transfer, thus providing the basis for future investigation of gene therapy as treatment for JAK3-deficient SCID.
We report fast charge state readout of a double quantum dot in a CMOS split-gate silicon nanowire transistor via the large dispersive interaction with microwave photons in a lumped-element resonator ...formed by hybrid integration with a superconducting inductor. We achieve a coupling rate \(g_0/(2\pi) = 204 \pm 2\) MHz by exploiting the large interdot gate lever arm of an asymmetric split-gate device, \(\alpha=0.72\), and by inductively coupling to the resonator to increase its impedance, \(Z_\text{r}=560~\Omega\). In the dispersive regime, the large coupling strength at the double quantum dot hybridisation point produces a frequency shift comparable to the resonator linewidth, the optimal setting for maximum state visibility. We exploit this regime to demonstrate rapid dispersive readout of the charge degree of freedom, with a SNR of 3.3 in 50 ns. In the resonant regime, the fast charge decoherence rate precludes reaching the strong coupling regime, but we show a clear route to spin-photon circuit quantum electrodynamics using hybrid CMOS systems.
Episodic cluster headache is a disabling neurologic disorder that is characterized by daily headache attacks that occur over periods of weeks or months. Galcanezumab, a humanized monoclonal antibody ...to calcitonin gene-related peptide, may be a preventive treatment for cluster headache.
We enrolled patients who had at least one attack every other day, at least four total attacks, and no more than eight attacks per day during a baseline assessment, as well as a history of cluster headache periods lasting at least 6 weeks, and randomly assigned them to receive galcanezumab (at a dose of 300 mg) or placebo, administered subcutaneously at baseline and at 1 month. The primary end point was the mean change from baseline in the weekly frequency of cluster headache attacks across weeks 1 through 3 after receipt of the first dose. The key secondary end point was the percentage of patients who had a reduction from baseline of at least 50% in the weekly frequency of cluster headache attacks at week 3. Safety was also assessed.
Recruitment was halted before the trial reached the planned sample size of 162 because too few volunteers met the eligibility criteria. Of 106 enrolled patients, 49 were randomly assigned to receive galcanezumab and 57 to receive placebo. The mean (±SD) number of cluster headache attacks per week in the baseline period was 17.8±10.1 in the galcanezumab group and 17.3±10.1 in the placebo group. The mean reduction in the weekly frequency of cluster headache attacks across weeks 1 through 3 was 8.7 attacks in the galcanezumab group, as compared with 5.2 in the placebo group (difference, 3.5 attacks per week; 95% confidence interval, 0.2 to 6.7; P = 0.04). The percentage of patients who had a reduction of at least 50% in headache frequency at week 3 was 71% in the galcanezumab group and 53% in the placebo group. There were no substantial between-group differences in the incidence of adverse events, except that 8% of the patients in the galcanezumab group had injection-site pain.
Galcanezumab administered subcutaneously at a dose of 300 mg once monthly reduced the weekly frequency of attacks of episodic cluster headache across weeks 1 through 3 after the initial injection, as compared with placebo. (Funded by Eli Lilly; ClinicalTrials.gov number, NCT02397473.).
The CRISPR-Cas9 system provides the ability to edit, repress, activate, or mark any gene (or DNA element) by pairing of a programmable single guide RNA (sgRNA) with a complementary sequence on the ...DNA target. Here we present a new method for small-molecule control of CRISPR-Cas9 function through insertion of RNA aptamers into the sgRNA. We show that CRISPR-Cas9-based gene repression (CRISPRi) can be either activated or deactivated in a dose-dependent fashion over a >10-fold dynamic range in response to two different small-molecule ligands. Since our system acts directly on each target-specific sgRNA, it enables new applications that require differential and opposing temporal control of multiple genes.
Capitalism and Slavery and the Civil War Oakes, James
International Labor and Working Class History,
01/2016, Letnik:
89, Številka:
89
Journal Article, Book Review
Recenzirano
Odprti dostop
They push in different directions, these two great debates. The first, on the relationship between capitalism and slavery, invites us to consider how closely the two systems were connected, to the ...point where more and more scholars argue that slavery itself was a form of capitalism. The second, on the origins of the American Civil War, highlights the fundamental difference and growing divergence between the free labor system of the North and the slave society of the South, to the point where some scholars see an irreconcilable conflict between the two. Can these competing tendencies be reconciled? Is it possible to define southern slavery as essentially “capitalist” without losing sight of the crucial distinctions between free and enslaved labor? A number of recent books suggest that scholars have begun to recognize the problem but have not quite figured out how to solve it.
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