Priming treatment with T-cell redirecting bispecific antibody ERY974 reduced cytokine induction without losing cytotoxic activity in vitro by changing the chromatin state in T cells.

CD3 bispecific constructs are anticipated to become an important form of cancer immunotherapy, but they frequently cause cytokine release syndrome (CRS) that is difficult to manage in clinical contexts. A combination of intra-patient dose escalation and immunosuppressive treatment is widely used to mitigate CRS. Studies suggest that CRS after subsequent doses of CD3 bispecific constructs is less severe than after the priming dose, and that step-up dosing reduces cytokine levels in animals and humans. However, the mechanism underlying the reduced cytokine induction after priming treatment with CD3 bispecific constructs is unclear. To understand human T-cell activation and chromatin states after priming treatment with CD3 bispecific construct targeting CD3ɛ and glypican 3 (ERY974), we examined cytokine levels, cytokine mRNA expression, CD3ɛ expression, CD3-mediated signal transduction, T cell activation markers, cytotoxicity against target cells, and chromatin states in T cells after ERY974 priming treatment or negative control. The second ERY974 treatment decreased cytokines on Day 8, and ERY974 priming treatment changed the chromatin state in T cells. CD3ɛ expression, CD3-mediated signal transduction, T cell activation markers, and cytotoxicity were similar between the priming treatment with ERY974 and negative control. The present study suggests that chromatin state changes in T cells after the priming treatment was a pivotal factor in the mitigation of cytokine release after the second ERY974 treatment.

Daily ascending dosing in cynomolgus monkeys to mitigate cytokine release syndrome induced by ERY22, surrogate for T-cell redirecting bispecific antibody ERY974 for cancer immunotherapy.

CD3 bispecific constructs show promising therapeutic potential as anti-tumor antibodies, but it has concurrently been difficult to manage cytokine release syndrome (CRS) in clinical use. Currently, the most effective measure for reducing CRS is considered a combination of intra-patient/animal dose escalation and corticosteroid premedication. To examine how effectively an intra-animal ascending dose regimen without premedication would mitigate CRS, we compared plasma cytokine levels in two groups of cynomolgus monkeys; one group was given a single dose, and the other a three-fold daily ascending dose of a CD3 bispecific construct that targets and cross-reacts with both glypican 3 and CD3 (ERY22). Ascending doses up to 1000 µg/kg of ERY22 dramatically reduced the peak cytokine levels of IL-6, TNF-α, and IFN-γ, IL-2 as well the clinical severity of CRS compared with a single dose of 1000 µg/kg. Peak cytokine levels following the single and ascending doses were 60,095 pg/mL and 1221 pg/mL for IL-6; 353 pg/mL and 14 pg/mL for TNF-α; 123 pg/mL and 16 pg/mL for IFN-γ; and 2219 pg/mL and 42 pg/mL for IL-2. The tolerance acquired with daily ascending doses up to 1000 µg/kg remained in effect for the following weekly doses of 1000 µg/kg.

Different players generate positive responses in two in vitro cytokine assay formats with aqueous and immobilized TGN1412 analog.

To detect potential risk of severe cytokine release syndrome, in vitro assay formats with human cells have been developed. The two major testing platforms are a combination of whole blood with aqueous-phase test articles (whole blood cytokine assay, WBCA) and peripheral blood mononuclear cells with solid-phase articles (PBMC assay). Significant induction of cytokines was seen in both assays after treatment with a widely used control agent, TGN1412 or its analog CD28SA, but the WBCA cytokine profile differed from what was expected from clinical experience. In the WBCA, potential risk of CD28SA was detected by elevation of IL-8 whereas IL-2, a key cytokine after stimulation of CD28, was not induced in approximately 40% of donor samples. Therefore, further mechanistic understanding of the different responses in the in vitro assay was needed. In this study of donor samples treated with CD28SA, we compared the induction of cytokines and identified the cytokine-producing cells in the two assays. IL-2 was markedly elevated in all the donors in the PBMC assay but only in 1 of 3 donors in the WBCA. IL-8, the most sensitive biomarker in the WBCA, was produced by monocytes and granulocytes. T cells, the most relevant player in the PBMC assay with CD28SA, did not contribute to the positive response seen in two donors in the WBCA, which suggests that different players caused the positive cytokine responses to CD28SA in the two assays.

Anesthetic management of nonintubated video-assisted thoracoscopic surgery using epidural anesthesia and dexmedetomidine in three patients with severe respiratory dysfunction.

Nonintubated video-assisted thoracoscopic surgery (VATS) has been reported to be safe and feasible for patients with various thoracic diseases, including those who have respiratory dysfunction. In nonintubated VATS, it is important to maintain spontaneous respiration and to obtain a satisfactory operating field through adequate collapse of the lung by surgical pneumothorax. Therefore, we need to minimize the patient's physical and psychological discomfort by using regional anesthesia and sedation. If analgesia and sedation are inadequate, conversion to intubated general anesthesia may be required. Dexmedetomidine (DEX) is a highly selective α2-adrenoceptor agonist that provides anxiolysis and cooperative sedation without respiratory depression. It seems to be a suitable sedative for nonintubated VATS, especially in high-risk patients for intubated general anesthesia, but there have been no report about its use combined with epidural anesthesia in nonintubated VATS for adult patients. Here, we report three patients with severe respiratory dysfunction who underwent nonintubated VATS for pneumothorax using epidural anesthesia and DEX. In all three patients, DEX infusion was started after placement of an epidural catheter and was titrated to achieve mild sedation, while maintaining communicability and cooperation. This seems to be a promising strategy for nonintubated VATS in patients with respiratory dysfunction, as well as patients with normal respiratory function.

Orthostatic intolerance during early mobilization following video-assisted thoracic surgery.

PURPOSE: Early postoperative mobilization is crucial for early ambulation to reduce postoperative pulmonary complications after lung resection. However, orthostatic intolerance (OI) may delay patient recovery, leading to complications. It is therefore important to understand the prevalence of and predisposing factors for OI following video-assisted thoracic surgery (VATS), which have not been established. This study evaluated the incidence of OI, impact of OI on delayed ambulation, and predisposing factors associated with OI in patients after VATS. METHODS: This retrospective cohort study consecutively analyzed data from 236 patients who underwent VATS. The primary outcome was defined as OI with symptoms associated with ambulatory challenge on postoperative day 1 (POD1), including dizziness, nausea and vomiting, feeling hot, blurred vision, or transient syncope. Multivariate logistic regression was performed to identify independent factors associated with OI. RESULTS: Of the 236 patients, 35.2 % (83) experienced OI; 45.8 % of these could not ambulate at POD1, compared with 15.7 % of patients without OI (P < 0.001). Factors independently associated with OI included advanced age [odds ratio 2.83 (1.46-5.58); P = 0.002], female gender [odds ratio 2.40 (1.31-4.46); P = 0.004], and postoperative opioid use [odds ratio 2.61 (1.23-5.77); P = 0.012]. Use of thoracic epidural anesthesia was not independently associated with OI [odds ratio 0.72 (0.38-1.37); P = 0.318]. CONCLUSION: Postoperative OI was common in patients after VATS and significantly associated with delayed ambulation. Advanced age, female gender, and postoperative opioid use were identified as independent predisposing factors for OI.

Preclinical in vitro evaluation of immune suppression induced by GYM329, Fc-engineered sweeping antibody.

Fc-engineering is commonly used to improve the therapeutic potency of antibody (Ab) treatments. Because FcγRIIb is the only inhibitory FcγR that contains an immunoreceptor tyrosine-based inhibition motif (ITIM), Fc-engineered Abs with enhanced binding affinity to FcγRIIb might provide immune suppression in clinical contexts. GYM329 is an anti-latent myostatin Fc-engineered Ab with increased affinity to FcγRIIb which is expected to improve muscle strength in patients with muscular disorders. Cross-linking of FcγRIIb by immune complex (IC) results in phosphorylation of ITIM to inhibit immune activation and apoptosis in B cells. We examined whether the IC of Fc-engineered Abs with enhanced binding affinity to FcγRIIb causes phosphorylation of ITIM or B cell apoptosis using GYM329 and its Fc variant Abs in human and cynomolgus-monkey (cyno) immune cells in vitro. IC of GYM329 with enhanced binding affinity to human FcγRIIb (×5) induced neither ITIM phosphorylation nor B cell apoptosis. As for GYM329, FcγRIIb should work as an endocytic receptor of small IC to sweep latent myostatin, so it is preferable that GYM329 induces neither ITIM phosphorylation nor B cell apoptosis to prevent immune suppression. In contrast, IC of myo-HuCy2b, the Ab with enhanced binding affinity to human FcγRIIb (×4), induced ITIM phosphorylation and B cell apoptosis. The result of the present study demonstrated that Fc-engineered Abs with similar binding affinity to FcγRIIb had different effects. Thus, it is important to also investigate FcγR-mediated immune functions other than binding to fully understand the biological effects of Fc-engineered Abs.

Postoperative continuous intravenous infusion of fentanyl is associated with the development of orthostatic intolerance and delayed ambulation in patients after gynecologic laparoscopic surgery.

PURPOSE: Early ambulation is essential for rapid functional recovery after surgery; however, orthostatic intolerance may delay recovery and cause syncope, leading to potential serious complications such as falls. Opioids may contribute to orthostatic intolerance because of reduced arterial pressure and associated reduction in cerebral blood flow and oxygenation. This study aimed to examine the effect of postoperative continuous infusion of fentanyl on orthostatic intolerance and delayed ambulation in patients after gynecologic laparoscopic surgery. METHODS: In this retrospective cohort study, data from 195 consecutive patients who underwent gynecologic laparoscopic surgery were analyzed to evaluate the association between postoperative continuous infusion of fentanyl and the incidence of orthostatic intolerance or delayed ambulation. The primary outcome was defined as delayed ambulation, an inability to ambulate on postoperative day 1. The secondary outcome was defined as orthostatic intolerance and symptoms associated with ambulatory challenge, including dizziness, nausea and vomiting, feeling hot, blurred vision, and eventual syncope. Multivariate logistic regression was used to determine the independent predictors of delayed ambulation and orthostatic intolerance. RESULTS: There were 24 cases with documented orthostatic intolerance and 5 with delayed ambulation. After multivariate logistic regression modeling, postoperative continuous infusion of fentanyl was found to be significantly associated with both orthostatic intolerance [adjusted odds ratio (95% confidence interval), 34.78 (11.12-131.72)] and delayed ambulation [adjusted odds ratio (95% confidence interval), 8.37 (1.23-72.15)]. CONCLUSION: Postoperative continuous infusion of fentanyl is associated with increased orthostatic intolerance and delayed ambulation in patients after gynecologic laparoscopic surgery.

The inhibitory effects of Orengedokuto on inducible PGE2 production in BV-2 microglial cells.

BACKGROUND AND AIM: Reactive microglia has been associated with neuroinflammation caused by the production of proinflammatory molecules such as cytokines, nitric oxide, and prostaglandins. The overexpression of these molecules may provoke neuronal damage that can cause neurodegenerative diseases. A traditional herbal medicine, Orengedokuto (OGT), has been widely used for treating inflammation-related diseases. However, how it influences neuroinflammation remains poorly understood. EXPERIMENTAL PROCEDURE: This study investigated the effects of OGT on inflammatory molecule induction in BV-2 microglial cells using real-time RT-PCR and ELISA. An in vivo confirmation of these effects was then performed in mice. RESULTS AND CONCLUSION: OGT showed dose-dependent inhibition of prostaglandin E2 (PGE2) production in BV-2 cells stimulated with lipopolysaccharide (LPS). To elucidate the mechanism of PGE2 inhibition, we examined cyclooxygenases (COXs) and found that OGT did not suppress COX-1 expression or inhibit LPS-induced COX-2 upregulation at either the transcriptional or translational levels. In addition, OGT did not inhibit COX enzyme activities within the concentration that inhibited PGE2 production, suggesting that the effect of OGT is COX-independent. The inhibitory effects of OGT on PGE2 production in BV-2 cells were experimentally replicated in primary cultured astrocytes and mice brains. OGT can be useful in the treatment of neuroinflammatory diseases by modulating PGE2 expression.

In vitro toxicological support to establish specification limit for anti-CD3 monospecific impurity in a bispecific T cell engager drug, ERY974.

An emerging structure for anti-tumor antibody drugs utilizes a bispecific antibody (BiAb) that recognizes a tumor surface antigen and CD3 on T cells. An impurity that commonly contaminates these BiAb products is an anti-CD3 monoclonal antibody (mAb). The most plausible cause of toxic activity by an anti-CD3 mAb is the induction of cytokines via T cell activation. In this in vitro study, we compared cytokine induction and T cell activation after treatment with an anti-glypican-3/CD3 BiAb (ERY974), anti-CD3 mAb impurity (aCD3), or ERY974 spiked with 5% aCD3. We found that contamination with up to 5% aCD3 did not affect cytokine release by ERY974. Cytokine levels induced by ERY974 in the presence of target cells were significantly higher than those induced by aCD3, but were very similar to those by the spiked treatment. The results supported the specification of a 5% limit for aCD3. OKT-3 had much higher activity to induce cytokines from peripheral blood mononuclear cells in an in vitro assay than aCD3. This suggests that specification limit should be decided for each type of anti-CD3 impurity that affects T cell-activating BiAb drug products. In vitro cytokine assays can provide useful information for determining these specification limits.

Maternal exposure to volatile anesthetics induces IL-6 in fetal brains and affects neuronal development.

Most clinically used general anesthetics have demonstrated neurotoxicity in animal studies, but the related mechanisms remain unknown. Previous studies suggest that anesthetics affect neuronal development through neuroinflammation, and significant effects of neuroinflammation on neurogenesis and neuronal disease have been shown. In the present study, we treated pregnant mice with 2% sevoflurane for 3 h at gestational day 15.5 and analyzed the expression of proinflammatory cytokines, including IL-6 and IL-17, in fetal mice brains. Sevoflurane induced IL-6 mRNA significantly, but did not upregulate IL-17. Other volatile anesthetics, including isoflurane, enflurane, and halothane, induced IL-6 mRNA in fetal brains as well as sevoflurane, but propofol did not. Sevoflurane and isoflurane showed the same effects in cultured microglia and astrocytes, but not in neurons. Because IL-6 induction in fetal brains may affect neuronal precursor cells (NPCs), numbers of NPCs in the subventricular zone were studied, revealing that maternal sevoflurane treatment significantly increases NPCs in offspring at 8 weeks after birth (p8wk). But this effect was absent in IL-6 knockout mice. Finally, behavioral experiments also revealed that maternal sevoflurane exposure causes learning impairments in p8wk offspring. These findings collectively demonstrate that maternal exposure to volatile anesthetics upregulates IL-6 in fetal mice brains, and the effects could result in long-lasting influences on neuronal development.

Is an in vitro whole blood cytokine assay useful to detect the potential risk of severe infusion reaction of monoclonal antibody pharmaceuticals?

After the life-threatening cytokine release syndrome (CRS) occurred in the clinical study of the anti-CD28 monoclonal antibody (mAb) TGN1412, in vitro cytokine release assays using human blood cells have been proposed for non-clinical evaluation of the potential risk of CRS. Two basic assay formats are frequently used: human peripheral blood mononuclear cells (PBMC) with immobilized mAbs, and whole blood with aqueous mAbs. However, the suitability of the whole blood cytokine assay (WBCA) has been questioned, because an unrealistically large sample size would be required to detect the potential risk of CRS induced by TGN1412, which has low sensitivity. We performed a WBCA using peripheral blood obtained from 68 healthy volunteers to compare two high risk mAbs, the TGN1412 analogue anti-CD28 superagonistic mAb (CD28SA) and the FcγR-mediated alemutuzumab, with a low risk mAb, panitumumab. Based on the cytokine measurements in this study, the sample size required to detect a statistically significant increase in cytokines with 90% power and 5% significance was determined to be n = 9 for CD28SA and n = 5 for alemtuzumab. The most sensitive marker was IL-8. The results suggest that WBCA is a practical test design that can warn of the potential risk of FcγR-mediated alemtuzumab and T-cell activating CD28SA but, because there was apparently a lower response to CD28SA, it cannot be used as a risk-ranking tool. WBCA is suggested to be a helpful tool for identifying potential FcγR-mediated hazards, but further mechanistic understanding of the response to CD28SA is necessary before applying it to T cell-stimulating mAbs.

Collaborative work on evaluation of ovarian toxicity. 10) Two- or four-week repeated dose studies and fertility study of di-(2-ethylhexyl) phthalate (DEHP) in female rats.

The main purpose of this collaborative work is to determine the optimal administration period required to detect toxic effects in evaluation of ovarian morphological changes in repeated-dose toxicity studies. To assess the morphological and functional changes induced in the ovaries by di-(2-ethylhexyl) phthalate (DEHP), two repeated-dose toxicity studies (repeated dose for 2 or 4 weeks) of DEHP administrated to female rats at dose levels of 0, 300, 1,000 and 3,000 mg/kg were conducted in collaboration with a female fertility study at the same dosages from 2 weeks prior to mating to Day 7 of pregnancy. Histopathology of the ovaries in both repeated-dose toxicity studies showed vacuolation of stromal cells in the groups receiving 300 mg/kg or more and an increase of large atretic follicles in groups at 1,000 mg/kg or more. In the 4-week study, a decrease in new corpora lutea was observed in the 3,000 mg/kg group. In the female fertility study, the 3,000 mg/kg group showed prolongation of the mean estrous cycle and irregular estrous cycles. Cesarean section revealed a decrease of pregnancy rate in the 3,000 mg/kg group. No effects on fertility or early embryonic development were found in groups at 1,000 mg/kg or less. These findings indicate that histopathological changes in the ovary are important endpoints for the evaluation of drugs which induce ovarian damage. In conclusion, for a repeated-dose toxicity study, a 2-week administration period is sufficient to detect ovarian toxicity caused by DEHP.