Immunomodulatory activity of heat-killed Lacticaseibacillus paracaseiMCC1849 based on the activation of plasmacytoid dendritic cells in the peripheral blood of healthy adults

Probiotics are widely used in food for their health benefits to the host. Inactivated probiotics also reportedly improve the intestinal environment and immune regulation. Our previous studies showed that heat-killed Lacticaseibacillus paracasei MCC1849 (hk-MCC1849) effectively induced IL-12 production in mouse spleen cells and significantly reduced cold symptoms in clinical trial subjects. To further elucidate the mechanism of host immune regulation by hk-MCC1849, human peripheral blood mononuclear cells (PBMCs) were cocultured with hk-MCC1849. The Toll-like receptor 9 ligands CpG-ODN 2216 and hk-MCC1849 and the heat-killed Lacticaseibacillus rhamnosus ATCC53103 were used as positive and negative controls, respectively. The results showed that, compared with the control, hk-MCC1849 significantly increased the expression of the plasmacytoid dendritic cell (pDC) marker CD86 (p < .0001) and the pDC marker HLA-DR (p < .001) in PBMCs. The expression levels of the IL-12p40, IFNα, IFNα1, IFNγ, and ISG15 genes were significantly increased after coculture with hk-MCC1849 (p < .05, p < .05, p < .05, p < .05, and p < .05, respectively, vs. control). Furthermore, to confirm whether hk-MCC1849 directly interacted with pDCs, DCs were enriched with PBMCs following 24 h of coculture with hk-MCC1849. Phagocytosis of fluorescently labeled hk-MCC1849 by pDCs was observed, and there were significant increases in CD86 (p < .05) and HLA-DR (p < .0001) expression in pDCs. These results suggest that hk-MCC1849 exerts a potential immunomodulatory effect on the host through the activation of peripheral pDCs.

An Exploratory Study on Seasonal Variation in the Gut Microbiota of Athletes: Insights from Japanese Handball Players

Despite accumulating evidence that suggests a unique gut microbiota composition in athletes, a comprehensive understanding of this phenomenon is lacking. Furthermore, seasonal variation in the gut microbiota of athletes, particularly during the off-season, remains underexplored. This study aimed to compare the gut microbiotas between athletic subjects (AS) and non-athletic subjects (NS), and to investigate variations between athletic and off-season periods. The data were derived from an observational study involving Japanese male handball players. The results revealed a distinct gut microbiota composition in AS compared with NS, characterized by significantly higher alpha-diversity and a greater relative abundance of Faecalibacterium and Streptococcus. Moreover, a comparative analysis between athletic and off-season periods in AS demonstrated a significant change in alpha-diversity. Notably, AS exhibited significantly higher alpha-diversity than NS during the athletic season, but no significant difference was observed during the off-season. This study demonstrates the characteristics of the gut microbiota of Japanese handball players and highlights the potential for changes in alpha-diversity during the off-season. These findings contribute to our understanding of the dynamic nature of the gut microbiota of athletes throughout the season.

Bifidobacterium breve M-16V regulates the autonomic nervous system via the intestinal environment: A double-blind, placebo-controlled study

We conducted a randomized controlled trial to investigate the potential of Bifidobacterium breve M-16 V to improve mood in humans. In this evaluation, we incorporated the use of near-infrared spectroscopy (NIRS), which has been used to evaluate mood states in studies with small sample sizes. Participants were given B. breve M-16 V (20 billion cells/day) for 6 weeks, and their mood state was assessed before and after ingestion. NIRS data were collected at rest and during a mental arithmetic task (under stress). Intake of B. breve M-16 V decreased the heart rate under stress and increased levels of the GABA-like substance pipecolic acid in stool samples. In addition, B. breve M-16 V improved mood and sleep scores in participants with high anxiety levels. These results suggest that B. breve M-16 V affects the metabolites of the gut microbiota and has the potential to modulate the autonomic nervous system and to improve mood and sleep.

Detailed dynamical features of the slow hydration water in the vicinity of poly(ethylene oxide) chains

Poly(ethylene oxide) (PEO) is a well-known biocompatible polymer and has widely been used for medical applications. Recently, we have investigated the dynamic behavior of hydration water in the vicinity of PEO chains at physiological temperature and shown the presence of slow water with diffusion coefficient one order of magnitude less than that of bulk water. This could be evidence for the intermediate water that is critical for biocompatibility; however, its detailed dynamical features were not established. In this article, we analyze the quasi-elastic neutron scattering from hydration water through mode distribution analysis and present a microscopic picture of hydration water as well as its relation to cold crystallization.

Screening of novel DPP-IV inhibitory peptides derived from bovine milk proteins using a peptide array platform

Dipeptidyl peptidase IV (DPP-IV) has become an important target in the prevention and treatment of diabetes. Although many DPP-IV inhibitory peptides have been identified by a general approach involving the repeated fractionation of food protein hydrolysates, the obtained results have been dependent on the content of each peptide and fractionation conditions. In the present study, a peptide array that provides comprehensive assays of peptide sequences was used to identify novel DPP-IV inhibitory peptides derived from bovine milk proteins; these peptides were then compared with those identified using the general approach. While the general approach identified only known peptides that were abundant in the hydrolysate, the peptide array-based approach identified 10 novel DPP-IV inhibitory peptides, all of which had proline at the second residue from the N-terminus. The proper or combined use of these two approaches, which have different advantages, will enable the efficient development of novel bioactive foods and drugs.

Effects of Heat-Killed Lacticaseibacillus paracasei MCC1849 on Immune Parameters in Healthy Adults-A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Study

Previous clinical studies have shown that heat-killed Lacticaseibacillus paracasei MCC1849 suppresses subjective symptoms among healthy adults. However, the mechanism underlying this beneficial effect remains unclear. This clinical study aimed to investigate the effects of MCC1849 on immune functions in humans. In this randomized, double-blind, placebo-controlled, parallel-group study, 100 healthy adults were randomly divided into MCC1849 or placebo groups. Participants ingested test powder with 5 × 1010 MCC1849 cells or placebo powder for 4 weeks. Immune functions were evaluated using expression levels of CD86 and HLA-DR on dendritic cells (DCs), neutrophils, and natural killer cells. The expression levels of interferon (IFN)-α, -β, and -γ in peripheral blood mononuclear cells incubated with Cpg2216 in vitro were quantified. Efficacy analysis was performed on participants in the per-protocol set (placebo group; n = 47, MCC1849 group; n = 49). The expression level of CD86 on pDCs and the gene expression levels of IFN-α, -β, and -γ upon TLR9 agonist stimulation were significantly higher in the MCC1849 group at 4 weeks. No side effects were observed. This is the first report to show the positive effects of MCC1849 on human immune cells. These findings reveal one possible mechanism of how MCC1849 suppresses subjective symptoms.

Human gut-associated Bifidobacterium species salvage exogenous indole, a uremic toxin precursor, to synthesize indole-3-lactic acid via tryptophan

Indole in the gut is formed from dietary tryptophan by a bacterial tryptophan-indole lyase. Indole not only triggers biofilm formation and antibiotic resistance in gut microbes but also contributes to the progression of kidney dysfunction after absorption by the intestine and sulfation in the liver. As tryptophan is an essential amino acid for humans, these events seem inevitable. Despite this, we show in a proof-of-concept study that exogenous indole can be converted to an immunomodulatory tryptophan metabolite, indole-3-lactic acid (ILA), by a previously unknown microbial metabolic pathway that involves tryptophan synthase β subunit and aromatic lactate dehydrogenase. Selected bifidobacterial strains converted exogenous indole to ILA via tryptophan (Trp), which was demonstrated by incubating the bacterial cells in the presence of (2-13C)-labeled indole and l-serine. Disruption of the responsible genes variedly affected the efficiency of indole bioconversion to Trp and ILA, depending on the strains. Database searches against 11,943 bacterial genomes representing 960 human-associated species revealed that the co-occurrence of tryptophan synthase β subunit and aromatic lactate dehydrogenase is a specific feature of human gut-associated Bifidobacterium species, thus unveiling a new facet of bifidobacteria as probiotics. Indole, which has been assumed to be an end-product of tryptophan metabolism, may thus act as a precursor for the synthesis of a host-interacting metabolite with possible beneficial activities in the complex gut microbial ecosystem.

The Potential Immunomodulatory Effect of Bifidobacterium longum subsp. longum BB536 on Healthy Adults through Plasmacytoid Dendritic Cell Activation in the Peripheral Blood

The interaction between the gut microbiota and the host can influence the host's immune system. Bifidobacterium, a commensal genus of gut bacteria, seems to have positive effects on host health. Our previous clinical research showed that B. longum subsp. longum BB536 enhanced innate and adaptive immune responses in elderly individuals with a lower grade of immunity, but the immunomodulatory mechanism is still unclear. In this study, dendritic cell (DC) surface markers in peripheral blood mononuclear cells isolated from healthy individuals were evaluated through coculture with heat-killed BB536. DC markers, innate immune activity and cytokine levels in plasma were also evaluated by a randomized, double-blind, placebo-controlled, parallel-group study (UMIN000045564) with 4 weeks of continuous live BB536 intake. BB536 significantly increased the expression of CD86 and HLA-DR on plasmacytoid DCs (pDCs) in vitro. Compared to placebo (n = 48), a significant increase in the expression of CD86 on peripheral pDCs was detected at week 4 of live BB536 intake (n = 49; 1 × 1010 CFU/day). Furthermore, coculture with hk-BB536 significantly increased the IFNγ expression level and demonstrated trends of increased IFNα1 and IFNβ expression. These findings suggest that consumption of BB536 has potential immunomodulatory effects on healthy individuals through the activation of peripheral pDCs.

Ligand-based, piggyBac-engineered CAR-T cells targeting EGFR are safe and effective against non-small cell lung cancers

Epidermal growth factor receptor (EGFR) is overexpressed in various cancers, including non-small cell lung cancer (NSCLC), and in some somatic cells at a limited level, rendering it an attractive antitumor target. In this study, we engineered chimeric antigen receptor (CAR)-T cells using the piggyBac transposon system, autologous artificial antigen-presenting cells, and natural ligands of EGFR. We showed that this approach yielded CAR-T cells with favorable phenotypes and CAR positivity. They exhibited potent antitumor activity against NSCLC both in vitro and in vivo. When administered to tumor-bearing mice and non-tumor-bearing cynomolgus macaques, they did not elicit toxicity despite their cross-reactivity to both murine and simian EGFRs. In total we tested three ligands and found that the CAR candidate with the highest affinity consistently displayed greater potency without adverse events. Taken together, our results demonstrate the feasibility and safety of targeting EGFR-expressing NSCLCs using ligand-based, piggyBac-engineered CAR-T cells. Our data also show that lowering the affinity of CAR molecules is not always beneficial.

Erratum: Ligand-based, piggyBac-engineered CAR-T cells targeting EGFR are safe and effective against non-small cell lung cancers

[This corrects the article DOI: 10.1016/j.omto.2023.100728.].

Relationship between office blood pressure and actual antihypertensive drug use in patients with hypertension following the promulgation of the guidelines for hypertension (JSH2019)

To achieve appropriate blood pressure control in the treatment of hypertension in Japan, this study examined the relationship between office blood pressure and actual antihypertensive drug use in general hospitals following the promulgation of the guidelines for hypertension (JSH2019). This study focused on blood pressure levels and drug use in outpatients on antihypertensive treatment from June to July 2020. The subjects were 2,537 patients classified into four groups based on their medical history, patients with: hypertension only; hypertension and cardiovascular disease; hypertension and dyslipidaemia; and hypertension and diabetes mellitus. The results showed a significant difference in systolic blood pressure (SBP) between patients with hypertension only and those with hypertension and cardiovascular disease (138.3±17.9 mmHg vs 135.6±19.9 mmHg, p<0.05). Regarding actual drug use, it was found that diuretics were prescribed more frequently in patients with hypertension and cardiovascular disease than in those with hypertension alone (15.5% vs 37.9%, p<0.05), even though the number of drugs for hypertension did not differ significantly. In addition, the dose of diuretics was greater only in patients with cardiovascular disease. These results show the actual drug use and blood pressure for each comorbidity. Furthermore, they suggest that the results of antihypertensive treatment may differ by changing the combination and dosage of antihypertensive drugs without changing the number of antihypertensive drugs used. The study also shows the problem of using less diuretics depending on the risk the patient has, and solving the problem may lead to achieving further antihypertensive goals.

Formate-producing capacity provided by reducing ability of Streptococcus thermophilus nicotinamide adenine dinucleotide oxidase determines yogurt acidification rate

Yogurt is made by fermenting milk with 2 lactic acid bacteria, Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus. To comprehensively understand the protocooperation mechanism between S. thermophilus and L. bulgaricus in yogurt fermentation, we examined 24 combinations of cocultures comprising 7 fast- or slow-acidifying S. thermophilus strains with 6 fast- or slow-acidifying L. bulgaricus strains. Furthermore, 3 NADH oxidase (Nox)-deficient mutants (Δnox) and one pyruvate formate-lyase deficient mutant (ΔpflB) of S. thermophilus were used to evaluate the factor that determines the acidification rate of S. thermophilus. The results revealed that the acidification rate of S. thermophilus monoculture determined the yogurt fermentation rates, despite the coexistence of L. bulgaricus, whose acidification rate was either fast or slow. Significant correlation was found between the acidification rate of S. thermophilus monoculture and the amount of formate production. Result using ΔpflB showed that the formate was indispensable for the acidification of S. thermophilus. Moreover, results of the Δnox experiments revealed that formate production required Nox activity, which not only regulated dissolved oxygen, but also the redox potential. The Nox provided the large decrease in redox potential required by pyruvate formate-lyase to produce formate. A highly significant correlation was found between formate accumulation and Nox activity in S. thermophilus. In conclusion, the formate production ability provided by the action of Nox activity determines the acidification rate of S. thermophilus, and consequently, regulates yogurt coculture fermentation.

Effects of Lactoferrin on Oral and Throat Conditions under Low Humidity Environments: A Randomized, Double-Blind, and Placebo-Controlled Crossover Trial

To evaluate the effects of a single ingestion of bovine lactoferrin (bLF) on oral and throat conditions under a low-humidity environment. A randomized, double-blind, 2-sequence, 2-treatment, and 2-period placebo-controlled crossover trial was conducted. Healthy adult subjects orally ingested bLF dissolved in water, or placebo water, followed by exposure to low humidity (20 °C, 20% relative humidity (RH)) for 2 h. The primary endpoint was subjective oral and throat discomfort assessed by a visual analog scale (VAS), which positively correlated with the discomfort. Secondary endpoints were unstimulated whole salivary flow rate (UWSFR) and salivary immunoglobulin A (IgA) secretion rate. Overall, 40 subjects were randomly assigned to two sequences (20 each) and 34 were analyzed. The VAS values for oral and throat discomfort in the bLF treatment were significantly lower than in the placebo treatment, whereas UWSFR and IgA secretion rates were comparable between the two treatments. Adverse drug reactions were not observed. Subjective oral and throat discomfort associated with low humidity is suppressed by a single ingestion of bLF. Our findings demonstrate the novel use of bLF in a clinical situation that leverages its unique characteristics.

Effects of Bovine Lactoferrin on the Maintenance of Respiratory and Systemic Physical Conditions in Healthy Adults-A Randomized, Double-Blind, Placebo-Controlled Trial

OBJECTIVES

We investigated the effects of bovine lactoferrin (LF) on the maintenance of the respiratory and systemic physical conditions.

METHODS

A randomized, double-blind, placebo-controlled trial was conducted. Healthy adults at Kyushu University of Health and Welfare ingested a placebo or bovine LF (200 mg/day) for 12 weeks. The primary endpoints were the total respiratory and systemic symptom scores. The secondary endpoint was the activity of plasmacytoid dendritic cells (pDCs) in peripheral blood.

RESULTS

A total of 157 subjects were randomized (placebo, n = 79; LF, n = 78), of whom, 12 dropped out. The remaining 145 participants were included in the full analysis set (placebo group, n = 77; LF group, n = 68). The total scores for respiratory and systemic symptoms during the intervention were significantly lower in the LF group than in the placebo group. The expression of CD86 and HLA-DR on pDCs was significantly higher in the LF group than in the placebo group at week 12. Adverse events were comparable between the groups, and no adverse drug reactions were observed.

CONCLUSIONS

These results suggest that orally ingested LF supports the normal immune system via maintaining pDC activity, and maintains respiratory and systemic physical conditions in healthy adults.

Effects of Heat-Killed Lacticaseibacillus paracasei MCC1849 on the Maintenance of Physical Condition in Healthy Adults: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Study

We previously reported that the intake of heat-killed Lacticaseibacillus paracasei MCC1849 suppressed the onset of cold-like symptoms in healthy young women who were susceptible to colds. This study aimed to investigate the effects of MCC1849 on subjective symptoms of physical condition in healthy adults of a wide age range. In this randomized, double-blind, placebo-controlled, parallel-group study, 200 healthy adults were randomly divided into the MCC1849 group or placebo group. The participants received test powder with 50 billion MCC1849 cells or placebo powder without MCC1849 for 24 weeks. Subjective symptoms were assessed by diary scores. Analysis was performed on 183 participants (MCC1849 group; n = 91, placebo group; n = 92) in the per-protocol set. The number of days of stuffy nose and cold-like symptoms was significantly reduced in the MCC1849 group compared with the placebo group. In addition, the duration of stuffy nose, sore throat and cold-like symptoms was significantly lower in the MCC1849 group. No side effects were observed. Therefore, oral intake of MCC1849 suppressed subjective symptoms in healthy adults of a wide age range. These data suggest that MCC1849 may help maintain physical condition.

First observation of 28O

Subjecting a physical system to extreme conditions is one of the means often used to obtain a better understanding and deeper insight into its organization and structure. In the case of the atomic nucleus, one such approach is to investigate isotopes that have very different neutron-to-proton (N/Z) ratios than in stable nuclei. Light, neutron-rich isotopes exhibit the most asymmetric N/Z ratios and those lying beyond the limits of binding, which undergo spontaneous neutron emission and exist only as very short-lived resonances (about 10-21 s), provide the most stringent tests of modern nuclear-structure theories. Here we report on the first observation of 28O and 27O through their decay into 24O and four and three neutrons, respectively. The 28O nucleus is of particular interest as, with the Z = 8 and N = 20 magic numbers1,2, it is expected in the standard shell-model picture of nuclear structure to be one of a relatively small number of so-called 'doubly magic' nuclei. Both 27O and 28O were found to exist as narrow, low-lying resonances and their decay energies are compared here to the results of sophisticated theoretical modelling, including a large-scale shell-model calculation and a newly developed statistical approach. In both cases, the underlying nuclear interactions were derived from effective field theories of quantum chromodynamics. Finally, it is shown that the cross-section for the production of 28O from a 29F beam is consistent with it not exhibiting a closed N = 20 shell structure.

Control survey and analysis for the KEK e-/e+ injector linac

A control survey technique using a laser tracker and a digital level was introduced to the KEK e-/e+ injector linac in 2020. Control surveys are continuously demonstrated during the machine's downtimes every summer. Analysis of the two-year data reproduces their trends in terms of the fiducial points on the beam line. In our paper, we report on systematic coordinates and their error distributions evaluated by a control survey, compare them with a numerical survey simulation, and discuss newly encountered issues.

Heat-Killed L. helveticus Enhances Positive Mood States: A Randomized, Double-Blind, Placebo-Controlled Study

When mood states are impaired, daily life is severely disrupted. To maintain a specific mood state, both positive and negative moods must be controlled; however, methods to maintain a positive mood have not been fully established. Previous studies have suggested that heat-killed L. helveticus MCC1848 has the potential to improve positive moods. This study aimed to test the efficacy of heat-killed L. helveticus MCC1848 in maintaining and improving a positive mood with PANAS, a questionnaire specifically designed to assess positive and negative mood, as the primary endpoint. Healthy Japanese nursing students (n = 46) were randomized to receive heat-killed L. helveticus MCC1848 (5 billion/day) or placebo powder for four weeks. Mood state was assessed before and two and four weeks after the intervention began; ingestion of heat-killed L. helveticus MCC1848 significantly improved PANAS 'Positive Affect' compared to the placebo. These results indicate that heat-killed L. helveticus MCC1848 is effective in enhancing positive mood.

Comprehensive genetic analyses of childhood acute leukemia in Iraq using next-generation sequencing

Background

Molecular analyses in hematological malignancies provide insights about genetic makeup. Probable etiological factors in leukemogenesis could also be disclosed. Since genetic analyses are still primitive in Iraq, a country of repeated wars, we conceived of performing next-generation sequencing (NGS), to disclose the genomic landscape of acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) among a cohort of Iraqi children.

Methods

Dried blood samples were collected from Iraqi children with ALL (n=55), or AML (n=11), and transferred to Japan where NGS was done. Whole-exome, whole-genome, and targeted gene sequencings were performed.

Results

Somatic point mutations and the copy number variations among Iraqi children with acute leukemia were comparable with those in other countries, and cytosine-to-thymine nucleotide alterations were dominant. Strikingly, TCF3-PBX1 was the most recurrent fusion gene (22.4%) in B-cell precursor ALL (B-ALL), and acute promyelocytic leukemia (AML-M3) was subtyped in 5 AML cases. Additionally, a high frequency of RAS signaling pathway mutations was detected in children with B-ALL (38.8%), along with 3 AML cases that carried oncogenic RAS.

Conclusions

Apart from disclosing the high frequency of TCF3-PBX1, NGS confirmed our previous finding of recurrent RAS mutations in Iraqi childhood acute leukemia. Our results suggest that the biology of Iraqi childhood acute leukemia is in part characteristic, where the war-aftermath environment or geography might play a role.

Heat-killed Lactobacillus helveticus improves mood states: a randomised, double-blind, placebo-controlled study

We investigated the effects of heat-killed Lactobacillus helveticus MCC1848 on daily mood states in healthy young adults. Participants (n=58) were randomised to receive heat-killed L. helveticus MCC1848 powder or placebo powder for 4 weeks. During the study period, adverse events were recorded in the participant diary. Mood states were assessed before and 2 and 4 weeks after initiation of the intervention. The primary outcomes were the shortened version of the Profile of Mood States 2 (POMS 2) scores. Secondary outcomes included other mood state (State-Trait Anxiety Inventory (STAI); visual analogue scale (VAS)), quality of life (acute form of the SF-36v2), sleep (Athens Insomnia Scale (AIS)) and fatigue (Chalder Fatigue Scale (CFS)) scores. Four weeks of heat-killed L. helveticus MCC1848 intake, compared to placebo, significantly improved the shortened version of the POMS 2 'friendliness' and the VAS 'relaxed' scores, which are two indicators of positive mood states. On the other hand, heat-killed L. helveticus MCC1848 intake had no significant effects on negative mood state items (e.g. anger, nervousness, confusion) assessed by the shortened version of the POMS 2, STAI and VAS. AIS and CFS scores also showed no significant differences. No adverse effects were observed with 4 weeks of heat-killed L. helveticus MCC1848 intake. These results suggest that daily consumption of heat-killed L. helveticus MCC1848 is safe and has the potential to improve positive mood states. UMIN Clinical Trial Registry: UMIN000043697.

Early Probiotic Supplementation of Healthy Term Infants with Bifidobacterium longum subsp. infantis M-63 Is Safe and Leads to the Development of Bifidobacterium-Predominant Gut Microbiota: A Double-Blind, Placebo-Controlled Trial

Bifidobacteria are important intestinal bacteria that provide a variety of health benefits in infants. We investigated the efficacy and safety of Bifidobacterium longum subsp. infantis (B. infantis) M-63 in healthy infants in a double-blind, randomized, placebo-controlled trial. Healthy term infants were given B. infantis M-63 (n = 56; 1 × 109 CFU/day) or placebo (n = 54) from postnatal age ≤ 7 days to 3 months. Fecal samples were collected, and fecal microbiota, stool pH, short-chain fatty acids, and immune substances were analyzed. Supplementation with B. infantis M-63 significantly increased the relative abundance of Bifidobacterium compared with the placebo group, with a positive correlation with the frequency of breastfeeding. Supplementation with B. infantis M-63 led to decreased stool pH and increased levels of acetic acid and IgA in the stool at 1 month of age compared with the placebo group. There was a decreased frequency of defecation and watery stools in the probiotic group. No adverse events related to test foods were observed. These results indicate that early supplementation with B. infantis M-63 is well tolerated and contributes to the development of Bifidobacterium-predominant gut microbiota during a critical developmental phase in term infants.

Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

Basophil activation test for allergic and febrile non-haemolytic transfusion reactions among paediatric patients with haematological or oncological disease

BACKGROUND AND OBJECTIVES

Allergic transfusion reactions (ATRs) and febrile non-haemolytic transfusion reactions (FNHTRs) are common, although their mechanisms remain unclear. Immunoglobulin E (IgE)-mediated type I hypersensitivity may be involved in the pathogenesis of ATR. A basophil activation test (BAT) may help elucidate this process.

MATERIALS AND METHODS

The BAT was based on peripheral blood samples from paediatric patients with a haematological or oncological disease and on samples of residual blood products transfused in each case. Dasatinib was used to evaluate whether basophil activation was mediated by an IgE-dependent pathway.

RESULTS

Twenty-seven patients with and 19 patients without ATR/FNHTR were included in this study, respectively. The median BAT values associated with ATR- (n = 41) and FNHTR-causing (n = 5) blood products were 22.1% (range = 6.1%-77.0%) and 27.8% (range = 15.2%-47.8%), respectively, which were higher than the median value of 8.5% (range = 1.1%-40.9%) observed in blood products without a transfusion reaction. Dasatinib suppressed basophil activity. BAT values were comparable in patients with ATR regardless of severity. Meanwhile, BAT values analysed with blood products non-causal for ATR/FNHTR were higher in patients with ATR/FNHTR than in those without.

CONCLUSION

The IgE-mediated type I hypersensitivity may be involved in the pathogenesis of ATR and FNHTR. BAT analyses may help elucidate the underlying mechanisms and identify patients at risk.

Lactulose Ingestion Induces a Rapid Increase in Genus Bifidobacterium in Healthy Japanese: A Randomised, Double-Blind, Placebo-Controlled Crossover Trial

Oral administration of a low dose of lactulose increases the abundance of genus Bifidobacterium in the large intestine; however, the details of the daily variation in Bifidobacterium have not been researched. To observe how the intestinal microbiota, including Bifidobacterium, change, especially immediately after the initiation of ingestion, we conducted a randomised, placebo-controlled, double-blind crossover study of ingestion of 4 g lactulose/day for 2 weeks in 36 healthy Japanese (including males and females). The primary outcome was the percentage of Bifidobacterium in the faecal bacteria. In the lactulose-treatment group, the percentage of Bifidobacterium was already significantly higher 2 days after starting lactulose ingestion than in the placebo group (20.5 ± 1.2% vs. 17.1 ± 1.2%, p = 0.021). Significant differences were maintained, gradually widening, until the end of the 2-week intervention period. There were significant increases in the percentage and the number of Bifidobacterium with ingestion of 4 g lactulose/day for 2 weeks, but no significant changes in the beta diversity of the intestinal microbiota between lactulose and placebo ingestion. The percentage of Bifidobacterium in the faecal bacteria returned to its original level within a week of the end of intervention with lactulose.

Lactoferrin and its digestive peptides induce interferon-α production and activate plasmacytoid dendritic cells ex vivo

Plasmacytoid dendritic cells (pDCs) recognise viral single-stranded RNA (ssRNA) or CpG DNA via Toll-like receptor (TLR)-7 and TLR9, and produce interferon (IFN)-α. Activated pDCs upregulate human leukocyte antigen (HLA)-DR and CD86 expression levels. Ingestion of bovine lactoferrin (LF) activates pDCs, but little is known about its effects. In this study, the effects of LF and its pepsin hydrolysate (LFH) on the production of IFN-α from peripheral blood mononuclear cells (PBMCs) and pDCs were examined. PBMCs were prepared from peripheral blood of healthy adults and incubated with LF, LFH, or lactoferricin (LFcin) in the absence or presence of ssRNA derived from human immunodeficiency virus. The concentration of IFN-α in the supernatant and the expression levels of IFN-α, HLA-DR, and CD86 in pDCs were quantified by enzyme-linked immunosorbent assay and flow cytometry. In the absence of ssRNA, the concentration of IFN-α was negligible and LF had no effect on it. In the presence of ssRNA, IFN-α was detected at a certain level, and LF and LFH significantly increased its concentration. The increase caused by LFH and LFcin were comparable. In addition, LF significantly upregulated the expression levels of IFN-α, HLA-DR, and CD86 in pDCs. LF and its digestive peptides induced IFN-α production and activated pDCs in the presence of ssRNA, suggesting that LF modulates the immune system by promoting pDC activation upon viral recognition.

Clinical research review: usefulness of bovine lactoferrin in child health

Lactoferrin (LF) is abundant in human milk and plays an important role in the health of children. Bovine LF (bLF) has high homology with human LF and has been reported to have multiple biological functions. Several clinical studies have been conducted considering these properties, which reported the usefulness of bLF. This review was aimed to provide an overview of the clinical evidence in children. We searched clinical reports investigating the effects of bLF in children and identified 36 studies on the role of bLF in infections, iron metabolism, body growth, cerebral development, and fecal microbiome. Considering the accumulated evidence, bLF may contribute to the child health, particularly by suppressing or alleviating gastrointestinal and respiratory symptoms, and improving the iron status of children with anemia or those at high risk of anemia. The dose of bLF varies depending on the expected effect and target age, but may not necessarily have to be as high as human LF in human milk. Some of the beneficial effects of bLF have not been fully validated due to limited clinical evidence or being observed in the secondary analysis of some studies. Further clinical evidence would add significant value to the use of bLF in child health.

Skin and soft tissue infections in adolescent chronic myeloid leukemia under dasatinib treatment

Although skin complications are common adverse events from tyrosine kinase inhibitors (TKIs) for the treatment of chronic myeloid leukemia (CML), no reports have focused on skin and soft tissue infections (SSTIs) associated with TKI use. We herein present five episodes of SSTIs in three CML patients under dasatinib treatment. All patients were adolescents and had been receiving dasatinib for more than 4 years. In contrast, none of 41 adult CML patients experienced SSTIs in a retrospective analysis. Our findings suggest that long-term dasatinib treatment in adolescent patients may be associated with the increased risk of SSTIs.

Abstract 5570: Development of piggyBac transposon-mediated HER2-CAR-T cells for the treatment of solid tumors

Background: Although chimeric antigen receptor (CAR)-T therapies have achieved remarkable success in the treatment of hematologic malignancies, the outcome for patients with solid tumors remains poor. There are several reasons behind this, including exhaustion of CAR-T cell, poor homing and penetration in the tumor, and the lack of persistence in the immunosuppressive tumor microenvironment. To solve these problems, we have developed HER2-CAR-T cells (BP2301) using the piggyBac (PB) transposon-based gene transfer system.

Methods and Results: Second generation HER2-CAR construct plus PB transposase were introduced into autologous peripheral blood mononuclear cells (PBMC) by electroporation. These cells were activated with UV-inactivated genetically-engineered antigen presenting autologous PBMC (AP cells) expressing HER2, CD80, and 4-1BBL, and propagated for 14 days to obtain the final product (BP2301). BP2301 exhibited dominant fraction of less exhausted stem cell memory-like T cells (Tscm), which could be associated with antitumor efficacy. BP2301 showed robust in vitro killing activity against HER2+ tumor cells even after multiple rounds of cancer cell challenge, suggesting the long-term functionality without immune-exhaustion. In a xenograft murine model of rhabdomyosarcoma cell line (SJCRh30), a single intravenous administration of BP2301 (5 × 106 CAR-positive cells) eradicated the tumor, and mice treated with BP2301 rejected the second tumor establishment owing to the in vivo expansion of BP2301.

Conclusion: BP2301 has demonstrated potent anti-tumor activity in vitro and in vivo. We have established a GMP manufacturing process for BP2301, completed non-clinical safety and efficacy studies, and plan to launch an investigator-initiated phase 1 clinical trial to evaluate the safety and efficacy of BP2301 in HER2-expressing sarcoma and gynecologic malignancies in the second quarter of 2022.

Citation Format: Koichiro Shioya, Tomio Matsumura, Yuta Ohira, Naomi Komatsuzaki, Manaka Shinagawa, Miyuki Tanaka, Shigeki Yagyu, Yozo Nakazawa, Lilin Zhang. Development of piggyBac transposon-mediated HER2-CAR-T cells for the treatment of solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5570.

AB0653 The association of autoantibodies with morbidity and mortality of scleroderma renal crisis in Japan

Background

The morbidity of scleroderma renal crisis (SRC) and autoantibodies in systemic sclerosis (SSc) vary by races and regions. Anti-RNA polymerase III is associated with SRC in America and European countries. However, the association of autoantibodies with SRC had not been elucidated in Japan.

Objectives

We aimed to investigate the association of autoantibodies with morbidity and mortality of SRC in Japan.

Methods

The clinical characteristics and mortality of 330 patients with systemic sclerosis (SSc) at Kyoto University Hospital were retrospectively analyzed, focusing on anti-centromere, anti-RNA polymerase III, anti-topoisomerase I, and anti-U1-RNP. Logistic regression analyses were performed to examine the association of autoantibodies with the development and mortality of SRC. Kaplan-Meier survival analysis was performed comparing the groups classified by autoantibodies.

Results

Anti-centromere (n = 177/318, 56%), anti-topoisomerase I (n = 80/311, 26%), anti-RNA polymerase III (n = 27/204, 13%), and anti-U1-RNP (n = 24/305, 8%) were found in SSc patients (n = 330). SRC was observed in 24 out of 330 SSc patients, including anti-topoisomerase I (n = 12/24, 50%), anti-RNA polymerase III (n = 7/24, 29%), anti-U1-RNP (n = 5/24, 21%), and anti-centromere (n = 3/24, 13%). Anti-U1-RNP (odds ratio [95% confidence interval], 3.63 [1.11–10.2]), anti-RNA polymerase III (3.29 [1.16–8.70]), and anti-topoisomerase I (3.22 [1.37–7.57]) were associated with the development of SRC. All patients with SRC were treated with ACE inhibitors and the 1-year survival rate was 54%. Anti-topoisomerase I was associated with the 1-year mortality of SRC (6.00 [1.11–41.1]). When the survival rate was compared between the patients positive for anti-topoisomerase I (n=12) and negative for anti-topoisomerase I (n=12), the 1-year survival rate was 33% vs 75% (p=0.041), respectively (Figure 1A). Furthermore, the 1-year survival of anti-centromere (100%), anti-RNA polymerase III (83%), and others/not detected (50%) were shown in patients negative for anti-topoisomerase I (Figure 1B).

Figure 1.

Overall survival of patients with SRC according to the type of autoantibodies.

(A) The survival rates in SRC patients who were positive for anti-topoisomerase I (solid line, n = 12) and those who were negative for anti-topoisomerase I (dotted line, n = 12).

(B) SRC patients negative for anti-topoisomerase I were classified as patients with anti-RNA polymerase III (dotted line, n = 6), anti-centromere (broken line, n = 2), and others/not detected (chain line, n = 4).

Conclusion

Specific SSc-related autoantibodies were associated with the morbidity and mortality in SRC.

References

[1]Nihtyanova SI, et al. Arthritis Rheumatol 2020;72(3):465-76.

[2]Hamaguchi Y, et al. Arthritis Rheumatol 2015;67(4):1045-52.

Table 1.

Univariate logistic regression analysis for mortality in SRC (n = 24).

VariablesOdds ratio (95% CI)P valueAge1.07 (0.99, 1.16)0.08Female sex3.00 (0.32, 66.6)0.38Diffuse/limited (diffuse %)0.25 (0.04, 1.36)0.12BMI0.67 (0.41, 0.93)0.049Modified Rodnan skin score0.95 (0.88, 1.02)0.15Digital ulcer0.52 (0.10, 2.63)0.43Reflux esophagitis0.60 (0.02, 17.1)0.73Pulmonary hypertension7.50 (1.17, 69.2)0.046Pleural effusion7.20 (1.23, 62.0)0.04Glucocorticoid use3.86 (0.65, 32.4)0.16Hemoglobin0.55 (0.25, 1.01)0.09Platelet1.00 (0.98, 1.01)0.44Total protein0.17 (0.02, 0.69)0.04Creatinine0.95 (0.67, 1.24)0.69CRP0.90 (0.67, 1.17)0.46Anti-topoisomerase I6.00 (1.11, 41.1)0.048Anti-centromere7.4x10-9 (--, 0.93)1.00Anti-RNA polymerase III0.36 (0.04, 2.18)0.29Anti-U1-RNP0.74 (0.08, 5.49)0.77

Disclosure of Interests

None declared

AB0470 THE ASSOCIATIONS OF ANTI-DNA ANTIBODIES WITH DISEASE ACTIVITY INDICES AND PATIENT REPORT OUTCOME PARAMETERS OF SLE IN KYOTO LUPUS COHORT

Background

Since the goals of remission or low disease activity are becoming more realistic with advances in treatment for SLE, there is a need to examine the measurements for SLE especially in patients with low disease activity. It has been known that disease activities in SLE are correlated with anti-DNA antibodies (Abs). However, it was not clear which measurements of disease activities or patient reported outcomes correlate better with anti-DNA Abs.

Objectives

To examine the association between parameters for SLE and anti-DNA Abs measured with RIA in Kyoto Lupus Cohort, a SLE registry in Kyoto University Hospital from 2019 to 2021.

Methods

1)Correlations between anti-DNA Abs with SLEDAI, M-SLEDAI (SLEDAI without anti-DNA Abs), VAS, LupusPRO, SF-36, and Systemic lupus erythematosus Symptom Checklist (SSC) were evaluated cross-sectionally (n = 310).

2)The alterations in SLE parameters and anti-DNA Abs between two visits were examined (n = 106). Further, the correlations within 3 months were examined in cases with flare-ups of SLE (the alteration in SLEDAI > 0 and anti-DNA Abs≧0, n = 39). The associations of the alterations of anti-DNA Abs with each item of SLEDAI classified by organs were also examined.

Results

1)31 percent of the cases in the entire registry was classified as remission or low disease activity (Table 1). SLEDAI (mean±SD) was higher in patients positive for anti-DNA Abs (7.94±5.20) than that in patients negative for anti-DNA Abs (4.56±4.65) (p < 0.0001). Anti-DNA Abs were weakly correlated with SLEDAI (R = 0.24 [p < 0.0001]), M-SLEDAI (R = 0.15 [p = 0.014]), and Physician-VAS (R = 0.19 [p = 0.0016]). On the other hand, there were no significant correlations between anti-DNA Abs and LupusPRO and SSC. Some dimensions in SF-36 had weak correlations with anti-DNA Abs, while no component summary scores had significant correlations with anti-DNA Abs.

Table 1.

Patients’ demographics and disease characteristics in the cohort (n = 310).

VariableResultsAge (years)47.7 (39.4, 57.5)Female sexn = 284 (91.6%)Disease duration (years)15.9 (9.4, 24.5)Anti-DNA Ab positivity†n = 106 (34.2%)Anti- DNA Ab titer (U/mL)4 (0, 8)SLEDAI4 (2, 8)SLEDAI<=4n = 162 (52.1%)SSC31 (16.2, 52.5)Remission or LDAn = 95 (30.7%)Patient-VAS38 (15, 52)Physician-VAS13.3 (3.3, 23.3)SF-36 PCS45.4 (36.6, 52.4)SF-36 MCS48.2 (41.5, 53.6)SF-36 RCS51.3 (42.6, 58.6)LupusPRO HQOL70.2 (54.8, 86.5)LupusPRO NHQOL41.7 (31.3, 51.0)Glucocorticoid (mg/day)5 (4, 8)

* Data are n (%) or median (Q1, Q3).

† Anti-DNA Ab positivity at the time of the cross-sectional observation.

2)No significant correlations were observed between the alterations of SLEDAI and anti-DNA Abs (R = 0.00 [95% CI: -0.23 – 0.22, p = 0.95]) in the total of patients with various range of observation periods (Figure 1A). In contrast, a significant correlation was observed (R = 0.32, p = 0.04) within 3 months after the flare-ups of SLE (Figure 1B). No significant correlations were found between the alterations in VAS and anti-DNA Abs, or the alterations of SSC and anti-DNA Abs. They showed the following organ symptoms: renal involvement, 62.8%; musculoskeletal, 17.1%; neuropsychiatric, 11.4%; hematological, 5.7%; mucocutaneous, 11.4%; serositis, 2.9%, and fever, 2.9%.

Figure 1.

The associations between the alteration in anti-DNA Ab and SLEDAI

Conclusion

The associations between anti-DNA Abs with several parameters of SLE were examined. Anti-DNA Abs correlated with disease activities (SLEDAI) in SLE patients, especially when observed in the condition of flare-up.

References

[1]Ho A, et al. Arthritis Rheum. 2001;44:2342-9.

Disclosure of Interests

None declared

Relationship between allergic transfusion reactions and allergic predisposition among pediatric patients with hematological/oncological disease

BACKGROUND

Allergic transfusion reactions (ATRs) manifest frequently as transfusion reactions, and their onset may be related to a patient's allergic predisposition. Moreover, although pediatric patients with hematological/oncological disease are more susceptible to ATRs, the relationship between allergic predisposition and ATRs remains to be fully clarified.

STUDY DESIGN AND METHODS

Patients who were diagnosed with pediatric hematological/oncological disease and received transfusion at the study institutions were included. We determined patient background information related to their allergy history, measured the levels of allergen-specific immunoglobulin E (IgE) using sera obtained on diagnosis, and analyzed their associations with ATR onset.

RESULTS

Of the 363 patients analyzed, 144 developed ATRs. Multivariate analysis identified cases with high basophils in the peripheral blood, and Dermatophagoides pteronyssinus- and egg white-specific IgEs were involved in the development of ATR in all age groups. Meanwhile, a history of food allergies, and positivity for Japanese cypress- and D. pteronyssinus-specific IgEs were risk factors for developing ATRs in the <5 years age group. Moreover, patients aged 5-<10 years with a history of asthma, allergic rhinitis, pollinosis, or atopic dermatitis, and those aged ≥10 years with positivity for dog dander-specific IgE were at risk for developing ATRs.

CONCLUSION

The allergic constitution of patients plays a role in ATR onset even in pediatric hematological/oncological diseases. Therefore, advance confirmation of a patient's allergic constitution may partly predict the onset of ATRs. However, since multiple allergic predispositions within complex mechanisms may be involved in the onset of ATRs, further verification is required.

PiggyBac Transposon-Mediated CD19 Chimeric Antigen Receptor-T Cells Derived From CD45RA-Positive Peripheral Blood Mononuclear Cells Possess Potent and Sustained Antileukemic Function

The quality of chimeric antigen receptor (CAR)-T cell products, namely, memory and exhaustion markers, affects the long-term functionality of CAR-T cells. We previously reported that piggyBac (PB) transposon-mediated CD19 CAR-T cells exhibit a memory-rich phenotype that is characterized by the high proportion of CD45RA⁺/C-C chemokine receptor type 7 (CCR7)⁺ T-cell fraction. To further investigate the favorable phenotype of PB-CD19 CAR-T cells, we generated PB-CD19 CAR-T cells from CD45RA⁺ and CD45RA⁻ peripheral blood mononuclear cells (PBMCs) (RA⁺ CAR and RA⁻ CAR, respectively), and compared their phenotypes and antitumor activity. RA⁺ CAR-T cells showed better transient gene transfer efficiency 24 h after transduction and superior expansion capacity after 14 days of culture than those shown by RA⁻ CAR-T cells. RA⁺ CAR-T cells exhibited dominant CD8 expression, decreased expression of the exhaustion marker programmed cell death protein-1 (PD-1) and T-cell senescence marker CD57, and enriched naïve/stem cell memory fraction, which are associated with the longevity of CAR-T cells. Transcriptome analysis showed that canonical exhaustion markers were downregulated in RA⁺ CAR-T, even after antigen stimulation. Although antigen stimulation could increase CAR expression, leading to tonic CAR signaling and exhaustion, the expression of CAR molecules on cell surface after antigen stimulation in RA⁺ CAR-T cells was controlled at a relatively lower level than that in RA⁻ CAR-T cells. In the in vivo stress test, RA⁺ CAR-T cells achieved prolonged tumor control with expansion of CAR-T cells compared with RA⁻ CAR-T cells. CAR-T cells were not detected in the control or RA⁻ CAR-T cells but RA⁺ CAR-T cells were expanded even after 50 days of treatment, as confirmed by sequential bone marrow aspiration. Our results suggest that PB-mediated RA⁺ CAR-T cells exhibit a memory-rich phenotype and superior antitumor function, thus CD45RA⁺ PBMCs might be considered an efficient starting material for PB-CAR-T cell manufacturing. This novel approach will be beneficial for effective treatment of B cell malignancies.

Precise Measurement of Differential Cross Sections of the Σ^{-}p→Λn Reaction in Momentum Range 470-650 MeV/c

The differential cross sections of the Σ^{-}p→Λn reaction were measured accurately for the Σ^{-} momentum (p_{Σ}) ranging from 470 to 650  MeV/c at the J-PARC Hadron Experimental Facility. Precise angular information about the Σ^{-}p→Λn reaction was obtained for the first time by detecting approximately 100 reaction events at each angular step of Δcosθ=0.1. The obtained differential cross sections show a slightly forward-peaking structure in the measured momentum regions. The cross sections integrated for -0.7≤cosθ≤1.0 were obtained as 22.5±0.68 [statistical error(stat.)] ±0.65 [systematic error(syst.)] mb and 15.8±0.83(stat)±0.52(syst)  mb for 470<p_{Σ}(MeV/c)<550 and 550<p_{Σ}(MeV/c)<650, respectively. These results show a drastic improvement compared with past measurements of the hyperon-proton scattering experiments. They will play essential roles in updating the theoretical models of the baryon-baryon interactions.

Recent progress and future prospects of hyperon nucleon scattering experiment

A new hyperon-proton scattering experiment, dubbed J-PARC E40, was performed to measure differential cross sections of the Σ+p, Σ−p elastic scatterings and the Σ−p → Λn scattering by identifying a lot of Σ particles in the momentum ranging from 0.4 to 0.8 GeV/c produced by the π±p → K+Σ± reactions. We successfully measured the differential cross sections of these three channels with a drastically improved accuracy with a fine angular step. These new data will become important experimental constraints to improve the theories of the two-body baryon-baryon interactions. Following this success, we proposed a new experiment to measure the differential cross sections and spin observables by using a highly polarized Λ beam for providing quantitative information on the ΛN interaction. The results of three Σp channels and future prospects of the Λp scattering experiment are described.

Impact of catheter ablation on functional tricuspid regurgitation in patients with atrial fibrillation

Background

Since atrial functional tricuspid regurgitation (AF-TR) is associated with increased heart failure and mortality, the management of AF-TR is clinically important. Atrial fibrillation (AF) plays the main role in AF-TR. However, the effectiveness of catheter ablation (CA) and mechanism of improvement of AF-TR haven't been fully evaluated.

Purpose

We sought to investigate the impact of CA for AF on AF-TR in patients with moderate or more TR.

Methods

We retrospectively investigated consecutive 2685 patients with AF who received CA from February 2004 to December 2019 in Japan. The current study population consisted of 102 patients with moderate or greater TR who underwent CA for AF. The echocardiographic parameters were compared between pre-ablation and post-ablation transthoracic echocardiography (TTE), and the recurrence rate of AF/ atrial tachycardia (AT) was measured.

Results

The mean age was 73.2 years, 53% were women. TR severity and TR jet area significantly improved after CA for AF (TR jet area: 5.8 [3.9–7.6] cm2 to 2.0 [1.1–3.0] cm2, p&lt;0.001). In addition, mitral regurgitation (MR) jet area, left atrial (LA) area, mitral valve diameter, right ventricular (RV) end-diastolic area, right atrial (RA) area, tricuspid valve (TV) diameter decreased after CA (p&lt;0.001, &lt;0.001, &lt;0.001, = 0.02, &lt;0.001, and &lt;0.001, respectively). There was no significant difference between one-year recurrence of AF/AT and TR severity at pre-ablation TTE (moderate 28.6%, moderate to severe 37.2%, and severe 31.6%, p=0.72).

Conclusions

TR severity and jet area improved after CA in patients with AF and moderate or more TR. RV size, RA size, TV diameter also decreased after CA, which may be associated with TR improvement. There was no significant difference between one-year recurrence of AF/AT and TR severity at pre-ablation TTE.

Funding Acknowledgement

Type of funding sources: None.

10-year clinical outcomes after radiofrequency catheter ablation for atrial fibrillation. A single center experience

Background

Radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) is becoming a routine procedure to treat patients with drug-refractory symptomatic AF. However, data regarding very long-term clinical outcomes is limited. The aim of the present study was to evaluate the 10-year clinical outcomes of patients who underwent RFCA for paroxysmal and persistent AF.

Methods

We retrospectively enrolled 503 consecutive patients (mean age 66,9±9,51 years; 71,6% male) who underwent RFCA for drug-refractory symptomatic AF between February 2004 and June 2011. Follow-up information was obtained using medical records and/or telephonic interviews with the patient, relatives and/or referring physicians.

Results

Among 503 patients enrolled in this study, 362 had paroxysmal atrial fibrillation (PAF) and 141 had persistent atrial fibrillation (PeAF) (72% and 28%, respectively). Mean follow-up was 8,84±3,05 years. The 10-year event-free rate for recurrent atrial tachyarrhythmia (AT) after the first procedure was 44,5% (49,4% for PAF vs 31,9% for PeAF; p=0,002 by log-rank test) and 81,9% after the last procedure (87,3% for PAF and 67,9% for PeAF; p≤0,001 by log-rank test). AT recurrence was observed most commonly during the first 12 months of the initial procedure (56%), with only 18% of them occurring after 60 months. Multivariate analysis revealed that persistent AF (hazard ratio=1,366; 95% confidence interval 1,058–1,76; p=0,017) and duration of AF &gt;5 years (hazard ratio=1,357; 95% confidence interval 1,064–1,732; p=0,005) were independent risk factors for AT recurrence. Regarding adverse events, there were 24 (4,8%) hospitalizations for acute decompensated heart failure, 20 (4%) ischemic strokes and 14 (2,8%) bleeding complications requiring hospital admissions. Patients taking oral anticoagulation and antiarrhythmic drugs at the end of the study accounted for 32,8% and 16,7% respectively.

Conclusions

RFCA for AF provided favorable results in terms of arrhythmia event-free survival in long-term follow-up with better results in patients with paroxysmal AF. Persistent AF and long-standing AF (beyond 5 years) were associated with AT recurrence. Despite the large number of patients who discontinued oral anticoagulation, thromboembolic adverse events were rare.

Funding Acknowledgement

Type of funding sources: None.

Favorable clinical response and drug retention of anti-IL-6 receptor inhibitor in rheumatoid arthritis with high CRP levels: the ANSWER cohort study

OBJECTIVE

Currently, biological disease-modifying anti-rheumatic drugs (bDMARDs) with different modes of action [tumour necrosis factor inhibitor (TNFi), interleukin-6 receptor inhibitor (IL-6Ri), or cytotoxic T-lymphocyte antigen 4-immunoglobulin (CTLA4-Ig)] are used in clinical practice to treat rheumatoid arthritis (RA). However, it is unclear which type of bDMARD is the most efficacious for a specific clinical situation. C-reactive protein (CRP) is an acute-phase reactant driven by IL-6 signalling. Here, we aimed to establish whether therapeutic efficacy differs between IL-6Ri and other bDMARDs with alternative modes of action in RA patients according to their CRP level.

METHOD

RA patients treated with bDMARDs were enrolled from an observational multicentre registry in Japan. Patients were classified into three groups according to baseline CRP tertiles. The overall 3 year retention rates of each bDMARD category were assessed. The Clinical Disease Activity Index (CDAI) was also assessed before and 3, 6, and 12 months after bDMARD initiation.

RESULTS

A total of 1438 RA patients were included and classified into three groups according to tertiles of baseline CRP levels (CRP¹, 0-0.3; CRP², 0.3-1.8; CRP³, 1.8-18.4 mg/dL). In CRP³, the overall 3 year drug retention rates were significantly higher for IL-6Ri than for TNFi and CTLA4-Ig (77.5 vs 48.2 vs 67.3, respectively). No significant difference was evident in terms of CDAI 12 months after bDMARD initiation in CRP¹-CRP³.

CONCLUSION

IL-6Ri may be a favourable therapeutic option over TNFi and CTLA4-Ig in RA patients with high CRP levels.

A lymphodepleted non-human primate model for the assessment of acute on-target and off-tumor toxicity of human chimeric antigen receptor-T cells

Objectives

Chimeric antigen receptor (CAR)‐T cell therapy possesses the potential to cause unexpected on‐target toxicities that may be life‐threatening. Non‐human primates (NHPs) share considerable structural homology and expression profiles of most proteins with humans and are therefore utilised as an animal model for non‐clinical safety studies. We have developed a lymphodepleted NHP model by conditioning the animals with immunosuppressive chemotherapy designed to simulate clinical practice conditions, to induce transient mixed chimerism before the administration of human CAR‐T cells redirected to target Ephrin type‐B receptor 4 (EPHB4‐CAR‐T cells) to evaluate the toxicity of these cells.

Methods

We administered 60 mg m⁻² day⁻¹ of fludarabine for 4 days and 30 mg kg⁻¹ day⁻¹ of cyclophosphamide for 2 days intravenously to cynomolgus macaques for lymphodepletion; then, 3.3 × 10⁶ kg⁻¹ of non‐transduced or EPHB4‐CAR‐T cells was infused into the macaques, respectively. All macaques were closely monitored and evaluated for potential toxicity for 7 days.

Results

Lymphodepletion was successfully achieved on day −1 before T‐cell infusion and persisted over 7 days without severe organ toxicities. A single administration of human EPHB4‐CAR‐T cells did not induce overt organ toxicities, although EPHB4‐CAR‐T cells were activated in vivo as evidenced by the elevation in copy numbers of the CAR transgene 24 h after infusion.

Conclusion

Although this NHP model is limited for the full evaluation of toxicity of human CAR‐T cells and the conditioning protocol should be further optimised, this lymphodepleted NHP model could be used to assess acute on‐target/off‐tumor toxicities of CAR‐T cells.

POS0345 CLINICOGENETIC STUDY OF FIVE NOVEL SUSCEPTIBILITY LOCI FOR TAKAYASU ARTERITIS: SUSCEPTIBILITY LOCI IN THE IL12B AND PTK2B REGION, BUT NOT THE LILRA3, DUSP22, KLHL33 REGIONS, ARE ASSOCIATED WITH VASCULAR DAMAGE IN TAKAYASU ARTERITIS

Background:

We have previously identified single nucleotide polymorphism (SNP) rs6871626 in IL12B, rs103294 in LILRA3, rs17133698 in DUSP22, rs2322599 in PTK2B, and rs1713450 in KLHL33 as non-HLA susceptibility loci in Takayasu arteritis (TAK) [1, 2]. However, the association of these SNPs with clinical features has scarcely investigated.

Objectives:

In this study, we aimed to examine how these SNPs contribute to clinical features and vascular damage in TAK.

Methods:

We enrolled 99 TAK patients who were enrolled in our previous genome-wide association study (GWAS) [2]. To assess vascular damage, Takayasu Arteritis Damage Score (TADS) and Vasculitis Damage Index (VDI) were measured at the last visit before November 2020. As for organ damages, the presence or absence of aortic regurgitation (AR), hypertension, ischemic heart disease, cerebrovascular event, visual loss, end-stage renal failure, and inflammatory bowel disease were evaluated. Treatment profiles including immunosuppressive drugs and vascular interventions were also reviewed.

Results:

The incidence of AR was positively associated with the risk allele of IL12B rs6871626 (p=0.0052; odds ratio (OR) 2.45, 95% confidence interval (CI) 1.27-4.73), and so was the proportion of patients who underwent aortic valve replacement (p=0.023; OR 3.64, 95% CI 1.08-12.24) (table 1). The incidence of hypertension was associated with the risk allele of IL12B rs6871626 (p=0.049; OR 1.82, 95% CI 0.99-3.36) and PTK2B rs2322599 (p=0.044; OR 2.52, 95% CI 0.97-6.54) (table 1). The proportion of biologic users tended to be higher in the risk genotypes of IL12B rs6871626 (p=0.15; OR1.80, 95% CI 0.79-3.99). Regarding vascular damage, there was positive correlation between TADS and the risk allele of IL12B rs6871626 (p=0.0035; β= 1.35) (Figure 1). Moreover, VDI was also positively correlated with the allele (p=0.0054; β= 0.96) (Figure 1). No other clinicogenetic associations were observed between five SNPs and vasculitis-associated damages.

Table 1.

The association of the five SNPs with aortic regurgitation and hypertension

Aortic regurgitationHypertensionOR (95% CI)p valueOR (95% CI)p valueIL12B rs68716262.45 (1.27-4.73)0.0052*1.82 (0.99-3.36)0.049*PTK2B rs23225991.21 (0.51-2.86)0.672.51 (0.97-6.54)0.044*LILRA3 rs1032941.16 (0.52-2.61)0.711.20 (0.55-1.64)0.64DUSP22 rs171336980.56 (0.28-1.13)0.0900.87 (0.46-1.63)0.66KLHL33 rs17134500.89 (0.42-1.91)0.771.48 (0.68-3.22)0.31

SNP, single nucleotide polymorphism; OR, odds ratio; CI, confidence interval

Conclusion:

In the present study, IL12B rs6871626 was closely correlated with vascular damage. We also found association between PTK2B rs2322599 and hypertension. There was no significant relevance between vascular damage and LILRA3 rs103294, DUSP22 rs17133698, or KLHL33 rs1713450.

References:

[1]Terao C et al. Am J Hum Genet. 2013;93(2):289-97.

[2]Terao C et al. Proc Natl Acad Sci U S A. 2018;115(51):13045-50.

Disclosure of Interests:

Keiichiro Kadoba: None declared, Ryu Watanabe Speakers bureau: I have received speaker’s fee from Mitsubishi Tanabe Pharma, Pfizer, Sanofi, AbbVie, Asahi Kasei, Eisai, Eli Lilly, Bristol-Myers Squibb, and Janssen., Takeshi Iwasaki: None declared, Koji Kitagori Grant/research support from: KK has received research grants from GlaxoSmithKline., Syuji Akizuki: None declared, Kosaku Murakami Speakers bureau: I have received speaking fees from Eisai Co. Ltd, Chugai Pharmaceutical Co. Ltd., Pfizer Inc., Bristol-Myers Squibb, Mitsubishi Tanabe Pharma Corporation, UCB Japan Co. Ltd, Daiichi Sankyo Co. Ltd. and Astellas Pharma Inc., Ran Nakashima: None declared, Motomu Hashimoto Speakers bureau: I have received a research grant and/or speaker fee from Bristol-Myers, Eisai, Ely Lilly, Mitsubishi Tanabe Pharma., Grant/research support from: I have received a research grant and/or speaker fee from Bristol-Myers, Eisai, Ely Lilly, Mitsubishi Tanabe Pharma., Masao Tanaka Speakers bureau: I have received research grants and/or speaker fees from AbbVie GK, Asahi Kasei Pharma Corporation, Astellas Pharma Inc., Bristol-Myers Squibb, Chugai Pharmaceutical Co., Ltd., Eisai Co., Ltd., Eli Lilly and Company, Pfizer Inc., UCB Japan Co., Ltd., Janssen Pharmaceutical K.K., Mitsubishi Tanabe Pharma Corporation, Novartis Pharma K.K., Taisho Pharma Co., Ltd, and Takeda Pharmaceutical Company Limited., Koichiro Ohmura Speakers bureau: I have received speaker’s fee from Abbvie, Actelion, Asahikasei Pharma, Astellas, AYUMI, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Eli Lilly, GSK, Janssen, JB, Mitsubishi Tanabe, Nippon Kayaku, Nippon Shinyaku, Novartis, Sanofi and Takeda., Grant/research support from: I have received research grants from GlaxoSmithKline., Akio Morinobu Speakers bureau: I have received speaking fees from Chugai Pharmaceutical Co. Ltd., Grant/research support from: I have received research grants from Chugai Pharmaceutical Co. Ltd., Chikashi Terao: None declared, Hajime Yoshifuji Speakers bureau: I have received lecture fees from Chugai., Consultant of: I have been an advisory board for a clinical trial conducted by Janssen.

POS1482-HPR PAIN CATASTROPHIZING IS ASSOCIATED WITH RESIDUAL PAIN AFTER REACHING IMPROVED CONDITIONS OF SWOLLEN/TENDER JOINTS AND SERUM C-REACTIVE PROTEIN LEVEL

Background:

It has long been recognized that immune-mediated inflammatory diseases, such as rheumatoid arthritis (RA), are prone to coexist with depression due to the effects of cytokines, and that these two illnesses lead to an elevation in patients’ pain. However, we often encounter patients with RA who suffer from residual pain despite an improvement in disease activity and inflammation. The specific psychological factors associated with residual pain have not yet been clarified. In addition to the traditional psychological factors, such as depression and anxiety, we focused on pain catastrophizing due to the distortion of pain perception and explored its association with residual pain.

Objectives:

To examine whether psychological factors, such as pain catastrophizing, depression, and anxiety, are associated with self-reported pain visual analogue scale (pain-VAS) scores in RA patients with 1 or less on 28joints- swollen/tender counts (SJC/TJC) and CRP.

Methods:

This was a cross-sectional study of 290 RA outpatients (85% of whom were women) with scores of less than 1 on SJC, TJC, and CRP, with a median (IQR) age of 66 (57–73) years. The participants completed questionnaires, including pain VAS (0–100 mm), Pain Catastrophizing Scale (PCS, 0–52 scale), and Hospital Depression and Anxiety Scale (HADS, 0–42 scale). Using linear regression analyses, we analysed whether PC (PCS ≥30), depression (HADS-D ≥11), and anxiety (HADS-A ≥11) (independent variables) were associated with pain VAS scores (dependent variable). After univariate regression analysis, multivariate analysis adjusted for confounding factors was performed.

Results:

Patients reported a wide range of pain severity with a median (range) pain VAS score of 9 (0–96mm). The prevalence of anxiety and depression were 5.5% and 5.9%, respectively. Meanwhile, 24.1% of the patients experienced pain catastrophizing. Pain catastrophizing was associated with pain VAS scores in univariate and multivariate analyses (Table 1). The presence of anxiety and depression was not associated with pain VAS scores in any model. Multivariate analysis of other covariates showed that age, disease duration, and presence of SJC/TJC of joints other than the 28 joints were positively correlated with pain VAS scores.

Table 1.

Univariate and multivariate regression analysis for independent variables associated with pain-VAS scores

UnivariateMultivariate independent variablesModel 1*Model 2**Pain catastrophizingEstimate3.74.13.695%CI 0.7 to 6.61.1 to 7.00.5 to 6.6p-value0.0150.0060.021AnxietyEstimate3.74.40.595%CI -1.9 to 9.2 -1.0 to 9.9 -3.5 to 7.9p value0.1980.1080.453DepressionEstimate3.54.23.995%CI -1.9 to 8.9 -1.1 to 9.5 -1.9 to 8.7p-value0.2040.1190.210

The covariates in multivariate analysis are as follows: age, sex, body mass index, disease duration, Steinbrocker’s Stage, prednisolone dosage, biologic agents use, and presence of swollen joint counts/tender joint counts of joints other than the 28 joints.

*Model 1: each psychological independent variable and the above covariates.

**Model 2: all psychological independent variables and the above covariates.

Conclusion:

Pain catastrophizing was associated with pain VAS scores in RA patients with 1 or less on 28joints-SJC/TJC and CRP, emphasising that residual pain in the patients should be treated in a biopsychosocial framework focussing on pain catastrophizing.

Disclosure of Interests:

Tamami Yoshida: None declared, Motomu Hashimoto Speakers bureau: Mitsubishi Tanabe Pharma Corporation; Bristol-Myers Squibb; Eisai Co., Ltd.; and Eli Lilly and Company., Grant/research support from: Mitsubishi Tanabe Pharma Corporation; Bristol-Myers Squibb; Eisai Co., Ltd.; and Eli Lilly and Company., Kosaku Murakami Speakers bureau: Eisai Co., Ltd.; Chugai Pharmaceutical Co., Ltd.; Pfizer Inc.; Bristol-Myers Squibb; Mitsubishi Tanabe Pharma Co; UCB Japan Co., Ltd.; Daiichi Sankyo Co., Ltd.; and Astellas Pharma Inc., Consultant of: Eisai Co., Ltd.; Chugai Pharmaceutical Co., Ltd.; Pfizer Inc.; Bristol-Myers Squibb; Mitsubishi Tanabe Pharma Co; UCB Japan Co., Ltd.; Daiichi Sankyo Co., Ltd.; and Astellas Pharma Inc., Koichi Murata Speakers bureau: Eisai Co., Ltd. and Astellas Pharma Inc., Consultant of: Eisai Co., Ltd. and Astellas Pharma Inc., Kohei Nishitani Grant/research support from: Asahi-Kasei Pharma., Ryu Watanabe Speakers bureau: Mitsubishi Tanabe Pharma Co; Pfizer Inc.; Sanofi S.A.; AbbVie GK; Asahi Kasei Pharma; Eisai Co., Ltd.; Eli Lilly and Company; Bristol-Myers Squibb; and Janssen Pharmaceutical K.K., Teruhide Koyama: None declared, Ritei Uehara: None declared, Masao Tanaka Speakers bureau: AbbVie GK, Asahi Kasei Pharma., Astellas Pharma Inc., Ayumi Pharmaceutical Co., Chugai Pharmaceutical Co., Ltd., Eisai Co., Ltd., Eli Lilly Japan K.K., Janssen Pharmaceutical K.K., Mitsubishi Tanabe Pharma Co., Novartis Pharma K.K., Pfizer Inc., Taisyo Pharma., Ltd., UCB Japan Co., Ltd., Grant/research support from: AbbVie GK, Asahi Kasei Pharma., Astellas Pharma Inc., Ayumi Pharmaceutical Co., Chugai Pharmaceutical Co., Ltd., Eisai Co., Ltd., Eli Lilly Japan K.K., Janssen Pharmaceutical K.K., Mitsubishi Tanabe Pharma Co., Novartis Pharma K.K., Pfizer Inc., Taisyo Pharma., Ltd., UCB Japan Co., Ltd., Hiromu Ito Grant/research support from: Bristol-Myers Squibb, Eisai Co, Taisyo Pharma., and Mochida., Shuichi Matsuda: None declared

POS0544 INFLUENCE OF EATING HABITS ON FRAILTY AMONG PATIENTS WITH RHEUMATOID ARTHRITIS: KURAMA COHORT

Background:

Rheumatoid arthritis (RA) is a chronic inflammatory disorder that contributes to accelerating frailty, a clinical state of increased vulnerability due to declined physiological function. Although accumulating evidence suggests the importance of nutritional therapy for frailty in the general population, there is little evidence on dietary recommendations for preventing frailty in patients with RA.

Objectives:

The present study aimed to reveal clinical associations between frailty status, eating habits and RA disease activity.

Methods:

We conducted a cross-sectional study of 306 female outpatients enrolled from the KURAMA (Kyoto University Rheumatoid Arthritis Management Alliance) cohort database. The participants were classified into three groups (robust, prefrail and frail) according to simplified frailty scale (SOF index), and dietary data were collected using a self-reported food frequency questionnaire as previously reported. We performed multivariate logistic analyses for the presence of frailty/prefrailty with or without eating habits.

Results:

Frail group showed physical decline such as decreased skeletal muscle index, hand grip strength and walking speed, and DAS28-ESR in the frail group was significantly higher compared to that in the others. In multivariate logistic analysis, the presence of frailty/prefrailty was correlated with DAS28-ESR (OR 1.71, p=0.00004) and methotrexate use (OR 0.47, p=0.0097). Cochran-Armitage trend test also showed that the intake frequency of five ingredients (meat, fish, milk, fruits and vegetables) was inversely associated with the prevalence of frailty/prefrailty. In additional multivariate logistic analyses with dietary habits, habitual intake of fish (at least three times per week), rather than meat or other foods, was independently correlated with the presence of frailty/prefrailty (OR 0.33, p=0.00027).

Conclusion:

Our results suggest that habitual intake of fish, rather than meat or other foods, may be beneficial in preventing frailty among RA patients.

References:

[1]Ferrucci, L. & Fabbri, E. Inflammageing: chronic inflammation in ageing, cardiovascular disease, and frailty. Nat Rev Cardiol 15, 505-522, doi:10.1038/s41569-018-0064-2 (2018).

[2]Hernandez Morante, J. J., Gomez Martinez, C. & Morillas-Ruiz, J. M. Dietary factors associated with frailty in old adults: a review of nutritional interventions to prevent frailty development. Nutrients 11, doi:10.3390/nu11010102 (2019).

Table 1.

Multivariate logistic analysis for RA patients with prefrailty or frailty

variables including eating habitsFish + MeatAllOR (95% CI)P valueOR (95% CI)P valueDAS28-ESR1.78 (1.34 - 2.37)0.000031.73 (1.30 - 2.30)0.00009MTX use0.43 (0.23 - 0.79)0.00550.42 (0.23 - 0.78)0.0050Age (1 year)1.02 (1.00 - 1.05)0.0371.03 (1.01 - 1.06)0.0015PSL use1.23 (0.69 - 2.21)0.491.22 (0.67 - 2.20)0.51Duration of RA (1 year)1.00 (0.98 - 1.02)0.721.00 (0.98 - 1.02)0.84Body mass index1.00 (0.93 - 1.07)0.980.99 (0.92 - 1.07)0.85Biological agents use1.02 (0.60 - 1.72)0.941.04 (0.62 - 1.77)0.87Fish dish0.31 (0.17 - 0.55)0.000040.33 (0.18 - 0.61)0.00027Meat dish0.86 (0.49 - 1.50)0.600.89 (0.51 - 1.57)0.69Milk0.71 (0.41 - 1.24)0.23Vegetable0.95 (0.47 - 1.93)0.89Fruits0.77 (0.41 - 1.42)0.40Figure 1.

The prevalence of prefrailty or frailty for subjects by intake frequency

Acknowledgements:

We thank S. Nakagawa and M. Iida for technical assistance.

Disclosure of Interests:

Masao Katsushima: None declared, Hiroto Minamino: None declared, Mie Torii: None declared, Motomu Hashimoto Speakers bureau: M.H. receives grants and/or speaker fees from Bristol-Meyers, Eisai, Eli Lilly, and Tanabe Mitsubishi., Grant/research support from: M.H. belongs to the department financially supported by Nagahama City, Shiga, Japan, Toyooka City, Hyogo, Japan and five pharmaceutical companies (Tanabe-Mitsubishi, Chugai, UCB Japan, Ayumi and Asahi-Kasei).

KURAMA cohort study is supported by a grant from Daiichi Sankyo Co. Ltd., Wataru Yamamoto: None declared, Ryu Watanabe Grant/research support from: R.W. belongs to the department that is financially supported by Nagahama City, Shiga, Japan, Toyooka City, Hyogo, Japan and five pharmaceutical companies (Tanabe-Mitsubishi, Chugai, UCB Japan, Ayumi and Asahi-Kasei). KURAMA cohort study is supported by a grant from Daiichi Sankyo Co. Ltd., Kosaku Murakami: None declared, Koichi Murata Grant/research support from: K.M. belongs to the department that is financially supported by Nagahama City, Shiga, Japan, Toyooka City, Hyogo, Japan and five pharmaceutical companies (Tanabe-Mitsubishi, Chugai, UCB Japan, Ayumi and Asahi-Kasei).

KURAMA cohort study is supported by a grant from Daiichi Sankyo Co. Ltd., Masao Tanaka Grant/research support from: M.T. belongs to the department that is financially supported by Nagahama City, Shiga, Japan, Toyooka City, Hyogo, Japan and five pharmaceutical companies (Tanabe-Mitsubishi, Chugai, UCB Japan, Ayumi and Asahi-Kasei).

KURAMA cohort study is supported by a grant from Daiichi Sankyo Co. Ltd., Hiromu Ito Speakers bureau: H.I. receives a research grant and/or speaker fee from Bristol-Myers, Eisai, Mochida, Taisho, and Asahi-Kasei., Grant/research support from: H.I. belongs to the department that is financially supported by Nagahama City, Shiga, Japan, Toyooka City, Hyogo, Japan and five pharmaceutical companies (Tanabe-Mitsubishi, Chugai, UCB Japan, Ayumi and Asahi-Kasei). KURAMA cohort study is supported by a grant from Daiichi Sankyo Co. Ltd., Akio Morinobu Speakers bureau: A.M. has received speaking fees and/or research grants from Eli Lilly Japan K.K., Ono Pharmaceutical Co., Pfizer Inc., UCB Japan, AbbVie G.K., Asahi Kasei Pharma and Chugai Pharmaceutical Co. Ltd., Grant/research support from: A.M. has received speaking fees and/or research grants from Eli Lilly Japan K.K., Ono Pharmaceutical Co., Pfizer Inc., UCB Japan, AbbVie G.K., Asahi Kasei Pharma and Chugai Pharmaceutical Co. Ltd.

Investigation of risk factors associated with erythrocyte engraftment after ABO-incompatible hematopoietic stem cell transplantation

ABO-incompatible hematopoietic stem cell transplantations (HSCTs) are widely practiced; however, the delay in erythrocyte engraftment can be problematic. While erythrocyte engraftment is usually indicated by an increase in reticulocyte levels without the need for erythrocyte transfusions, the disappearance of recipient-derived anti-A/B isoagglutinin and detection of donor-derived A/B antigens can also be used as other parameters. We conducted a retrospective analysis of 68 ABO-incompatible HSCTs, focusing on major and bidirectional mismatch. We analyzed known clinical risk factors associated with delayed erythrocyte engraftment using the three parameters (disappearance of anti-A/B isoagglutinin in recipient, detection of donor-derived A/B antigen, and reticulocyte levels >1%). Although the three parameters were well correlated, the results showed heterogeneity when analyzing the associated risk factors for delayed erythrocyte engraftment. In the analysis of all cases, the requirement for an HLA-matched platelet transfusion was a common risk factor. Furthermore, erythrocyte engraftment was slower in adults than in children. In adults, cytomegalovirus antigenemia was a risk factor for two parameters; however, in children, underlying disease was a common risk factor for all parameters. There is a complex relationship between erythrocyte engraftment and various factors related to HSCTs. Our results suggest that greater accuracy is possible by using analysis methods other than the measurement of reticulocyte levels.

Mutated GM-CSF-based CAR-T cells targeting CD116/CD131 complexes exhibit enhanced anti-tumor effects against acute myeloid leukaemia

Objectives

As the prognosis of relapsed/refractory (R/R) acute myeloid leukaemia (AML) remains poor, novel treatment strategies are urgently needed. Clinical trials have shown that chimeric antigen receptor (CAR)‐T cells for AML are more challenging than those targeting CD19 in B‐cell malignancies. We recently developed piggyBac‐modified ligand‐based CAR‐T cells that target CD116/CD131 complexes, also known as the GM‐CSF receptor (GMR), for the treatment of juvenile myelomonocytic leukaemia. This study therefore aimed to develop a novel therapeutic method for R/R AML using GMR CAR‐T cells.

Methods

To further improve the efficacy of the original GMR CAR‐T cells, we have developed novel GMR CAR vectors incorporating a mutated GM‐CSF for the antigen‐binding domain and G4S spacer. All GMR CAR‐T cells were generated using a piggyBac‐based gene transfer system. The anti‐tumor effect of GMR CAR‐T cells was tested in mouse AML xenograft models.

Results

Nearly 80% of the AML cells predominant in myelomonocytic leukaemia were found to express CD116. GMR CAR‐T cells exhibited potent cytotoxic activities against CD116⁺ AML cells in vitro. Furthermore, GMR CAR‐T cells incorporating a G4S spacer significantly improved long‐term in vitro and in vivo anti‐tumor effects. By employing a mutated GM‐CSF at residue 21 (E21K), the anti‐tumor effects of GMR CAR‐T cells were also improved especially in long‐term in vitro settings. Although GMR CAR‐T cells exerted cytotoxic effects on normal monocytes, their lethality on normal neutrophils, T cells, B cells and NK cells was minimal.

Conclusions

GMR CAR‐T cell therapy represents a promising strategy for CD116⁺ R/R AML.