Discovery and characterization of a selective IKZF2 glue degrader for cancer immunotherapy

Malignant tumors can evade destruction by the immune system by attracting immune-suppressive regulatory T cells (Treg) cells. The IKZF2 (Helios) transcription factor plays a crucial role in maintaining function and stability of Treg cells, and IKZF2 deficiency reduces tumor growth in mice. Here we report the discovery of NVP-DKY709, a selective molecular glue degrader of IKZF2 that spares IKZF1/3. We describe the recruitment-guided medicinal chemistry campaign leading to NVP-DKY709 that redirected the degradation selectivity of cereblon (CRBN) binders from IKZF1 toward IKZF2. Selectivity of NVP-DKY709 for IKZF2 was rationalized by analyzing the DDB1:CRBN:NVP-DKY709:IKZF2(ZF2 or ZF2-3) ternary complex X-ray structures. Exposure to NVP-DKY709 reduced the suppressive activity of human Treg cells and rescued cytokine production in exhausted T-effector cells. In vivo, treatment with NVP-DKY709 delayed tumor growth in mice with a humanized immune system and enhanced immunization responses in cynomolgus monkeys. NVP-DKY709 is being investigated in the clinic as an immune-enhancing agent for cancer immunotherapy.

Sonic vibrational analysis provides continuous measurement of arterial properties

OBJECTIVE

We describe a new technology for measuring artery mechanical properties, called Sonic Vibrational Analysis (SVA). We utilize SVA to study the changes in radial artery smooth muscle tone caused by intravenous infusion of vasoactive agents.

METHODS

Six healthy volunteers were monitored with a radial intra-arterial catheter and an SVA sensor during progressively increasing doses of nitroglycerin (NTG), phenylephrine, sodium nitroprusside (SNP), dobutamine, and nicardipine. In SVA, the propagation velocity of an audio-frequency vibration is measured over a short segment of the radial artery. The measurement has sufficient temporal resolution to track the continuous changes in arterial properties that occur due to the natural blood pressure pulse.

RESULTS

Coupled with the measurement of radial blood pressure, SVA allowed determination of the physiological/mechanical state of the artery within a single cardiac cycle. NTG, SNP, and phenylephrine caused significant changes in both blood pressure and the physiological state of the radial artery. Nicardipine and dobutamine altered blood pressure without change in the state of the radial artery.

CONCLUSIONS

The current results are consistent with previous studies of the effects of vasoactive agents on the radial artery. SVA is non-invasive, continuous, localized to a well-defined section of artery, and suitable for the collection of large volumes of time-resolved data in a laboratory or clinical setting.

Quasi-metastable quartet levels in alkalilike atoms and ions

We describe the properties of a subclass of quartet levels of alkalilike atoms and ions that often retain metastability against autoionization and may have large radiative yields. Gain cross sections for XUV lasers with wavelengths between 20 and 100 nm are given.

KrF laser with a phase-conjugate Brillouin mirror

We report observation of phase conjugation by stimulated Brillouin scattering using KrF-laser radiation (248 nm). The backscattered signal consists of both phase-conjugate and non-phase-conjugate components, which have different temporal behavior. This phase-conjugate Brillouin mirror has been used in a double-pass KrF laser-amplifier system, and as an element in a KrF-laser resonator, to compensate for aberrations and to produce a diffraction-limited output beam.

Phase conjugation of KrF laser radiation

Phase conjugation of radiation from a KrF laser (249 nm) is reported using degenerate four-wave mixing in CS(2) and in a variety of saturable absorbers. Dependence on input intensity and medium concentration is investigated. Reflectivities greater, similar2.5% have been measured. A thermal phase grating seems to be the mechanism involved.

Resonantly enhanced rare-gas-halide laser frequency up-conversion in Mg vapor

Frequency up-conversion of XeCl-laser radiation (308 nm) and KrF-laser radiation (249 nm) by two-photon resonantly enhanced four-wave mixing in Mg vapor is reported. A dye laser tuned to two-photon resonance with the 3s-3d(1)D(2) Mg level was used. The dependences of generated signals at 127 and 115 nm on input intensity and number density were investigated. No saturation was observed up to 4 x 10(9) W/cm(2) (249 nm) and 6 x 10(8) W/cm(2) (308 nm). The 115-nm signal was phase matched by using Xe. Conversion efficiencies and signal linewidths are discussed.