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• Atherosclerosis reflects intrahepatic immunity in the setting of hepatic ischemia/reperfusion injury (IRI). • Atherosclerosis mouse model (ApoE-/-) livers exhibited more damage than wild-type (WT) livers after hepatic IRI. • The expression of interleukin (IL)-15 and its transcriptional regulator, interferon regulatory factor -1 (IRF-1), in ApoE-/- mouse livers were upregulated compared with that in WT mouse livers, leading to the activation of intrahepatic T and NK cells. Abdominal aortic calcification (AAC) is associated with cardiovascular-related mortality, along with an elevated risk of coronary, cerebrovascular, and cardiovascular events. Notably, AAC is strongly associated with poor overall and recurrence free survival posthepatectomy for hepatocellular carcinoma. Despite the acknowledged significance of atherosclerosis in systemic inflammation, its response to ischemia/reperfusion injury (IRI) remains poorly elucidated. In this study, we aimed to clarify the impact of atherosclerosis on the liver immune system using a warm IRI mouse model. Injury was induced in an atherosclerotic mouse model (ApoE−/−) or C57BL/6J wild-type (WT) mice through 70% clamping for 1 hour and analyzed after 6 hours of reperfusion. Elevated serum levels of aspartate and alanine aminotransferase, along with histological assessment, indicated considerable damage in the livers of ApoE−/− mice than that in WT mice. This indicates a substantial contribution of atherosclerosis to IRI. Furthermore, T and natural killer (NK) cells in ApoE−/- mouse livers displayed a more inflammatory phenotype than those in WT mouse livers. Reverse transcription-polymerase chain reaction analysis revealed a significant upregulation of interleukin (IL)-15 and its transcriptional regulator, interferon regulatory factor-1 (IRF-1) in ApoE−/− mouse livers compared with that in WT mouse livers. These findings suggest that in an atherosclerotic mouse model, atherosclerosis can mirror intrahepatic immunity, particularly activating liver NK and T cells through IL-15 production, thereby exacerbating hepatic damage. The upregulation of IL-15 expression is associated with IRF-1 overexpression. [ABSTRACT FROM AUTHOR]

The molecular and cellular mechanism for clearance of dead neurons was explored in the developing Drosophila optic lobe. During development of the optic lobe, many neural cells die through apoptosis, and corpses are immediately removed in the early pupal stage. Most of the cells that die in the optic lobe are young neurons that have not extended neurites. In this study, we showed that clearance was carried out by cortex glia via a phagocytosis receptor, Draper (Drpr). drpr expression in cortex glia from the second instar larval to early pupal stages was required and sufficient for clearance. Drpr that was expressed in other subtypes of glia did not mediate clearance. Shark and Ced-6 mediated clearance of Drpr. The Crk/Mbc/dCed-12 pathway was partially involved in clearance, but the role was minor. Suppression of the function of Pretaporter, CaBP1 and phosphatidylserine delayed clearance, suggesting a possibility for these molecules to function as Drpr ligands in the developing optic lobe. • Dead young neurons in the developing optic lobe were cleared by cortex glia via the Draper/Shark/Ced-6 pathway. • Drpr expression in cortex glia from the second instar larval to early pupal stages was required. • The Crk/Mbc/dCed-12 pathway was partially involved in clearance, but the role was minor. • A possibility was suggested that Pretaprter, CaBP1 and phosphatidylserine mediate clearance as Drpr ligands. [ABSTRACT FROM AUTHOR]

Abstract: CYP2C9 is a human microsomal cytochrome P450c (CYP). Much variation in CYP2C9 levels and activity can be attributed to polymorphisms of this gene. Wild‐type CYP2C9 and ten mutants were co‐expressed with NADPH‐cytochrome P450 reductase in Escherichia coli. The hydroxylase activities toward steroids were examined. CYP2C9.2, CYP2C9.3, CYP2C9.4, CYP2C9.16, CYP2C9.28, CYP2C9.48 and CYP2C9.52 had higher testosterone 6β‐hydroxylation than CYP2C9.1. CYP2C9.4 showed higher progesterone 6β‐hydroxylation activity than CYP2C9.1. CYP2C9.28 and CYP2C9.48 showed higher progesterone 11α‐hydroxylation activity than CYP2C9.1. CYP2C9.48 showed higher progesterone 16α‐hydroxylation activity than CYP2C9.1. CYP2C9.2, CYP2C9.3, CYP2C9.16 and CYP2C9.30 had higher estrone 16α‐hydroxylation activity than CYP2C9.1. CYP2C9.3 had higher estrone 11α‐hydroxylation activity than CYP2C9.1. CYP2C9.39 and CYP2C9.57 showed similar activities to CYP2C9.1. These results indicate that the substrate specificity of CYP2C9.39 and CYP2C9.57 was not changed, but CYP2C9.2, CYP2C9.3, CYP2C9.4, CYP2C9.16, CYP2C9.28, CYP2C9.30, CYP2C9.48 and CYP2C9.52 showed different hydroxylation activities toward steroids compared with CYP2C9.1. [ABSTRACT FROM AUTHOR]

Hepatic irradiation for the treatment of hepatobiliary malignancies often indirectly damages liver tissue and promotes the development of liver fibrosis. However, little is known concerning the effects of hepatic irradiation on the liver immune system, including natural killer (NK) cells. The aim of this study was therefore to investigate how hepatic irradiation influences the functions and characteristics of liver resident NK cells. An established murine hepatic irradiation model was used to examine the specific effects of hepatic irradiation on immune cell populations and metastasis. This analysis demonstrated that hepatic irradiation decreased the number of liver resident NK cells (DX5–TRAIL+), but did not affect the total NK number or proportions of NK cells in the liver or spleen. This effect was correlated with the hepatic irradiation dose. Surprisingly, the liver resident NK population had not recovered by two months after hepatic irradiation. We also found that hepatic irradiation limited the cytotoxic effects of liver-derived lymphocytes against a mouse hepatoma cell line and promoted hepatic metastases in an in vivo model, although adoptive transfer of activated NK cells could alleviate metastatic growth. Finally, we demonstrated that hepatic irradiation disrupted the development of liver-resident NK cells, even after the adoptive transfer of precursor cells from the bone marrow, liver, and spleen, suggesting that irradiation had altered the developmental environment of the liver. In summary, our data demonstrated that hepatic irradiation abolished the DX5–TRAIL+ liver-resident NK cell population and dampened antitumor activities in the liver for at least two months. Additionally, hepatic irradiation prevented differentiation of precursor cells into liver-resident NK cells. [ABSTRACT FROM AUTHOR]

CYP2C9 is a human microsomal cytochrome P450c (CYP). Much of the variation in CYP2C9 levels and activity can be attributed to polymorphisms of this gene. Wild-type CYP2C9 and mutants were coexpressed with NADPH-cytochrome P450 reductase in Escherichia coli. The hydroxylase activities toward 7-ethoxycoumarin, flavanone and steroids were examined. Six CYP2C9 variants showed Soret peaks (450 nm) typical of P450 in reduced CO-difference spectra. CYP2C9.38 had the highest 7-ethoxycoumarin de-ethylase activity. All the CYP2C9 variants showed lower flavanone 6-hydroxylation activities than CYP2C9.1 (the wild-type). CYP2C9.38 showed higher activities in testosterone 6β-hydroxylation, progesterone 6β−/16α-hydroxylation, estrone 11α-hydroxylation and estradiol 6α-hydroxylation than CYP2C9.1. CYP2C9.40 showed higher testosterone 17-oxidase activity than CYP2C9.1; CYP2C9.8 showed higher estrone 16α-hydroxylase activity and CYP2C9.12 showed higher estrone 11α-hydroxylase activity. CYP2C9.9 and CYP2C9.10 showed similar activities to CYP2C9.1. These results indicate that the substrate specificity of CYP2C9.9 and CYP2C9.10 was not changed, but CYP2C9.8, CYP2C9.12 and CYP2C9.40 showed different substrate specificity toward steroids compared with CYP2C9.1; and especially CYP2C9.38 displayed diverse substrate specificities towards 7-ethoxycoumarin and steroids. [ABSTRACT FROM AUTHOR]

Carcinoembryonic antigen (CEA) is a classic tumor-specific antigen that is overexpressed in several cancers, including gastric cancer. Although some anti-CEA antibodies have been tested, to the best of our knowledge, there are currently no clinically approved anti-CEA antibody therapies. Because of this, we have created the novel anti-CEA antibody, 15-1-32, which exhibits stronger binding to membrane-bound CEA on cancer cells than existing anti-CEA antibodies. 15-1-32 also shows poor affinity for soluble CEA; thus, the binding activity of 15-1-32 to membrane-bound CEA is not influenced by soluble CEA. In addition, we constructed a 15-1-32-monomethyl auristatin E conjugate (15-1-32-vcMMAE) to improve the therapeutic efficacy of 15-1-32. 15-1-32-vcMMAE showed enhanced antitumor activity against gastric cancer cell lines. Unlike with existing anti-CEA antibody therapies, antitumor activity of 15-1-32-vcMMAE was retained in the presence of high concentrations of soluble CEA. [ABSTRACT FROM AUTHOR]

Hepatic amyloid light-chain ( AL) amyloidosis is characterized by abnormal deposition of amyloid fibrils in the liver. As this precursor protein is produced by a proliferative plasma cell clone in the bone marrow, liver transplantation ( LT) does not affect the disease's progression. Here, we describe the successful treatment using bortezomib- and dexamethasone-based chemotherapy, following LT, of hepatic AL amyloidosis in a 65-year-old woman with progressive liver failure. The patient presented with progressive hepatic dysfunction accompanied by hepatorenal syndrome requiring hemodialysis, and living donor LT was successfully performed. Histology revealed amyloid deposits in the liver and stomach, and serum immunofixation revealed AL amyloidosis (κ-type). The patient began chemotherapy on day 45 after the LT, and remission was achieved after one course. She was subsequently discharged 83 days after the LT, with normal liver and renal function, and no clinical evidence of recurrent disease was observed at the latest follow up (22 months post- LT). [ABSTRACT FROM AUTHOR]

• The relation between follicular helper T cell–related single nucleotide polymorphisms (SNPs) and de novo donor-specific antibody (dnDSA) formation was investigated. • The SNPs in CXCR5 and CTLA4 were associated with dnDSA formation. • Follicular helper T cell–related SNPs can be biomarkers of dnDSA formation. Risk prediction of de novo donor-specific antibody (dnDSA) formation is crucial for understanding the long-term prognostic impact of kidney transplantation (KT). Recently, follicular helper T (Tfh) cells, a subtype of CD4+ T cells, have been reported to play an important role in dnDSA formation after solid organ transplantation. Given the growing recognition of the importance of Tfh cells in generating a strong humoral immune response, we examined whether polymorphisms in Tfh cell–related molecules were associated with dnDSA formation after KT. Eighty-three patients who underwent living-donor KT between January 2013 and February 2020 at Hiroshima University Hospital were included in the study. Six Tfh cell–related molecules (BCL6, CXCR5, CXCL13, ICOS, CD40L, and IL21) that are important for Tfh cell differentiation and maturation in secondary lymphoid tissues were investigated. CTLA4, which is important for Tfh-cell activation, was also investigated. Single nucleotide polymorphisms (SNPs) in the genes for these molecules were detected using Taq Man SNP genotyping and evaluated for their association with dnDSA formation after KT. Of the 83 KT recipients, 8 developed dnDSAs during the observation period. No statistically significant differences were observed in the baseline characteristics between patients with and without dnDSA formation, except for donor age. Among the 7 Tfh cell–related molecules, the incidence of dnDSA formation was associated with CXCR5 and CTLA4 SNPs. Furthermore, combining these 2 SNPs enabled more significant stratification of dnDSA formation. Our findings indicate that genetic polymorphisms in Tfh cell–related molecules are predisposing factors for dnDSA formation after KT. [ABSTRACT FROM AUTHOR]

• Efforts to minimize rewarming during vascular anastomosis improve graft outcomes. • A thermal barrier bag keeps the graft cooler even with prolonged anastomosis. • In long anastomosis time, the thermal barrier bag is preferred. In kidney transplantation (KT), efforts to minimize rewarming and optimize anastomosis time during vascular anastomosis improve graft outcomes. We recently reported the safety and efficacy of a pouch-type thermal barrier bag (TBB) made of elastomer gel to reduce second-warm ischemic injury during vascular anastomosis. We aimed to examine the usefulness of the TBB in prolonged vascular anastomosis in KT performed by young transplant fellows. Young transplant fellows performed KT under the supervision of certified transplant surgeons. The kidney graft was placed inside the TBB with an outlet for vessels and preserved during vascular anastomosis. A non-contact infrared thermometer measured the graft surface temperature before and after vascular anastomosis. After completion of the anastomosis, the TBB was manually slid out of the transplanted kidney and removed before graft reperfusion. Clinical data, including patient characteristics and perioperative variables, were collected. The primary endpoint was the median graft surface temperature at the end of the anastomosis. Ten living-donor kidney transplant recipients with a median age of 56.5 years (range, 40–69 years) underwent KT procedures performed by young transplant fellows. The median anastomosis time was 53 (43–67) min. At the end of anastomosis, the median graft surface temperature was 17.7°C (16.3–18.3°C); no serious adverse events or delayed graft function were observed. The TBB can keep transplanted kidneys at a low temperature even with prolonged vascular anastomosis time, thus contributing to the functional preservation of transplanted kidneys and stable transplant outcomes. [ABSTRACT FROM AUTHOR]

Abstract: Sulfonylureas promote insulin secretion and potently lower blood glucose levels, however, they induce hypoglycemia and undergo a reduction in efficacy when administered long-term (secondary failure). The dipeptidyl peptidase (DPP)-IV inhibitor ASP8497, (2S,4S)-4-fluoro-1-({[4-methyl-1-(methylsulfonyl)piperidin-4-yl]amino}acetyl)pyrrolidine-2-carbonitrile monofumarate, inhibits the degradation of glucagon-like peptide-1 (GLP-1), an incretin hormone, and promotes insulin secretion in a glucose-dependent manner. ASP8497 is therefore less likely to induce hypoglycemia and less likely to show reduced efficacy even after repeated administration. Here, to determine whether or not ASP8497 improves glucose tolerance in Zucker fatty rats, we examined the effects of ASP8497 and gliclazide, a sulfonylurea, on glucose tolerance after repeated administration. We also developed an animal model of secondary failure using streptozotocin–nicotinamide-induced diabetic mice. Results: ASP8497 (3mg/kg) improved glucose intolerance in Zucker fatty rat without any attenuation (blood glucose AUC: P =0.034 vs. vehicle) while gliclazide (10mg/kg) did not (P =0.916 vs. vehicle). Furthermore, ASP8497 (3, 10mg/kg) was found to effect glucose tolerance dose-dependently (3mg/kg: P =0.230, 10mg/kg: P =0.003 vs. glibenclamide (10mg/kg)) by enhancing insulin secretion in mice inadequately controlled with glibenclamide. Our results suggest that ASP8497 may be effective even in patients with secondary failure who are unable to maintain satisfactory glycemic control using sulfonylureas. [Copyright &y& Elsevier]

Abstract: The novel hypoglycemic agent, YM440 ((Z)-1,4-bis{4-[(3,5-dioxo-1,2,4-oxadiazolidin-2-yl) methyl] phenoxy}but-2-ene) is a ligand of the peroxisome proliferator-activated receptor, (PPAR) γ. YM440 has been shown to counteract insulin resistance in diabetic rodent models. However, it is not clear whether this compound has a significant effect on hyperlipidemia in vivo. Hyperlipidemia has been reported to be a risk factor for the early development of renal disease. The aim of this study is to examine the effects of chronic treatment with YM440 on hyperlipidemia and renal injury in obese Zucker fatty (ZF) rats. Treatment of 8-week-old ZF rats with YM440 (100 mg/kg/day) for 16 weeks decreased plasma triglyceride and cholesterol concentrations. YM440 markedly reduced the rate of progression of both albuminuria and proteinuria. YM440 normalized urinary N-acetyl-β-d-glucosaminidase (NAG) activity, which is a marker for renal proximal tubular damage, and ameliorated the rise in systolic blood pressure compared to the vehicle control. YM440 also blocked the development of nephromegaly. Histological analyses revealed that both glomerular area expansion and tubular cast accumulation gradually lessened in YM440-treated ZF rats. Regression analyses between the plasma triglyceride levels and the renal parameters (urinary protein excretion and albumin excretion) indicated that the renal parameters correlated positively with the plasma triglyceride levels. In conclusion, the hypolipidemic effects of YM440 prevent renal injury in ZF rats. YM440 might be useful for preventing the early development of diabetic nephropathy in subjects with type 2 diabetes by ameliorating metabolic control problems. [Copyright &y& Elsevier]

Abstract: Peroxisome proliferator-activated receptor γ (PPARγ) has been reported to play an important role to regulate adiposity and insulin sensitivity. It is not clear whether antagonism of PPARγ using a synthetic ligand has significant effects on adipose tissue weight and glucose metabolism in vivo. The aim of this study is to examine the effects of a synthetic PPARγ antagonist (GW9662) on adiposity and glycemic control in high-fat (HF) diet-fed mice. First the properties of GW9662 as a PPARγ antagonist were estimated in vitro. GW9662 displaced [3H]rosiglitazone from PPARγ with K i values of 13nM, indicating that the affinity of GW9662 for PPARγ was higher than that of rosiglitazone (110nM). GW9662 had no effect on PPARγ transactivation in cells expressing human PPARγ. Treatment of 3T3-L1 preadipocytes with GW9662 did not increase aP2 expression or [14C]acetic acid uptake. GW9662 did not recruit transcriptional cofactors to PPARγ. Limited trypsin digestion of the human PPARγ/GW9662 complex showed patterns of digestion distinct from those of rosiglitazone. This suggests that the binding characteristics between GW9662 and PPARγ are different from those of rosiglitazone. Treatment of HF diet-fed mice with GW9662 revealed that this compound prevented HF diet-induced obesity without affecting food intake. GW9662 suppressed any increase in the amount of visceral adipose tissue, but it did not change HF diet-induced glucose intolerance. These data indicate that antagonism of PPARγ using a synthetic ligand suppresses the increased adiposity observed in HF diet-induced obesity, and that a PPARγ antagonist could possibly be developed as an anti-obesity drug. [Copyright &y& Elsevier]

Using a glucose clamp, we had shown that YM440, (Z)-1,4-bis{4-[(3,5-dioxo-1,2,4-oxadiazolidin-2-yl)methyl]phenoxy}but-2-ene, reduced the increased hepatic glucose output in obese Zucker rats. We further examined effects of YM440 on 14C-incorporation from [14C]bicarbonate into blood glucose via gluconeogenesis, and on gluconeogenic enzymatic activities. Fed obese Zucker rats showed a 4-fold increase of 14C-incorporation into blood glucose compared to that in lean rats. Glucose-6-phosphatase and fructose-1,6-bisphosphatase activities in obese rats were increased 1.4-fold and 1.6-fold compared with lean rats. YM440 (300 mg/kg for 2 weeks) decreased 14C-incorporation into blood glucose by 29% in obese rats. Glucose-6-phosphatase but not fructose-1,6-bisphosphatase activity was reduced by YM440 and closely correlated with 14C-incorporation into blood glucose, indicating a key role for glucose-6-phosphatase in hepatic glucose output. These results suggest that the increased gluconeogenesis in obese rats is mainly due to the increased activities of glucose-6-phosphatase and fructose-1,6-bisphosphatase and that YM440 suppresses hepatic glucose output by reducing glucose-6-phosphatase activity. [Copyright &y& Elsevier]

Peroxisome proliferator-activated receptor (PPAR) γ is a ligand-inducible transcription factor mediating glucose and lipid metabolism. Prior studies showed that YM440 ameliorated hyperglycemia in diabetic mice without affecting body fat weight or PPARγ transactivation. In this study we have examined further the effects of YM440 on PPARγ binding, transactivation and conformational change. YM440, pioglitazone and rosiglitazone displaced [3H]rosiglitazone from PPARγ with Ki values of 4.0, 3.1, and 0.20 μM, indicating that YM440 was comparable to pioglitazone and 20-fold less potent than rosiglitazone. Although pioglitazone and rosiglitazone increased both PPARγ transactivation in cells expressing human full-length PPARγ2 or GAL4-PPARγ and mRNA expression of PPARγ responsive genes in 3T3-L1 cells, YM440 had weak effects on PPARγ transactivation and mRNA expression being 550- to 790-fold and 36- to 110-fold less active than rosiglitazone, respectively. YM440 and rosiglitazone induced interaction between PPARγ and the transcriptional cofactor, p300 or SRC-1, but YM440 was 151- and 1091-fold less potent than rosiglitazone, respectively. The weak transcriptional activity of YM440 was not due to poor cell permeability. Limited trypsin digestion of the full-length human PPARγ2 with YM440 or rosiglitazone showed distinct patterns of digestion, suggesting a difference in the conformational change of PPARγ. When db/db mice were treated with YM440 (100 mg/kg) for 28 days, YM440 increased hepatic glucokinase expression but not adipose tissue FABP and UCP1 expression, indicating a tissue selective expression of PPARγ-related genes. Unique properties regarding the binding-transactivation of PPARγ by YM440 may lead to the hypoglycemic activity without affecting body fat weight in diabetic mice. [Copyright &y& Elsevier]

Reports on the production of a large amount of dye-decolorizing peroxidase, DyP in Aspergillus oryzae under the control of the alpha-amylase promoter. Activity yield of the purified recombinant DyP; Exhibition by rDyP without a typical heme-binding region produced by A. oryzae of a function similar to that of native DyP.

• Postoperative NLR is a useful factor for predicting prognosis in patients after LDLT with HCC. • The activation of infused NK cells is inversely correlated with decreased postoperative NLR. • Immunotherapy using activated NK cells may improve postoperative NLR and long-term prognosis. Preoperative neutrophil-to-lymphocyte ratio (NLR) is a well-known prognostic indicator in various malignancies; however, the impact of postoperative NLR on living donor liver transplant (LDLT) recipients is unknown. Immunotherapy with donor liver-derived activated natural killer (NK) cells may improve postoperative NLR by coactivating immune cells or suppressing activated neutrophils. This study aims to clarify the clinical significance of postoperative NLR in recipients after LDLT with HCC and assess whether immunotherapy improves postoperative NLR. We conducted a retrospective study of LDLT recipients between 2001 and 2022 to evaluate the clinical significance of postoperative NLR. Furthermore, the correlation between postoperative NLR and the activation marker of infused NK cells was also evaluated. The postoperative NLR was examined 4 weeks after LDLT. The postoperative high NLR group (N = 78) had preoperative lower NLR and higher model for end-stage liver disease and a higher rate of postoperative infection within 30 days after LDLT than the postoperative low NLR group (N = 41). Postoperative high NLR (hazard ratio [HR], 2.62; 95% confidence interval [CI], 1.01-6.79; P =.047) and nontreatment of immunotherapy (HR, 3.10; 95% CI, 1.33-7.22; P <.01) were independent risk factors for poor overall survival in multivariate analysis. Furthermore, the activation marker of infused NK cells is inversely correlated with decreased postoperative NLR. The higher level of postoperative NLR was independently associated with poor prognosis in patients after LDLT with HCC. Immunotherapy using activated NK cells may improve postoperative NLR and long-term prognosis. [ABSTRACT FROM AUTHOR]

• Anti-donor T-cell responses are not necessarily attenuated during cytomegalovirus infection. • Anti-third-party T-cell responses are attenuated before cytomegalovirus infection. • Caution is exercised in reducing the dose of immunosuppressants in cytomegalovirus infection. Cytomegalovirus (CMV), the most common opportunistic infection of kidney transplantation (KT), is preventable by prophylactic and preemptive antiviral drugs in CMV-immunoglobulin (Ig)G–positive donors. Our preemptive therapy optimized immunosuppressive doses based on mixed lymphocyte response (MLR) results, regardless of preoperative CMV-IgG serostatus pairing. This study used the MLR to compare the anti-donor T-cell responses between CMV antigenemia-positive and -negative cases. One hundred patients underwent KT using a cyclosporine (CsA)-based immunosuppressive regimen at Hiroshima University Hospital. CMV antigenemia-positive cells were defined as 4/50,000 CMVpp65-positive cells. T-cell responses to allo-antigens were measured using MLR assays to evaluate patients' anti-donor immune reactivity. After analyzing the proliferation of CD4+ and CD8+ T-cell subsets, the stimulation indices of CD4+ or CD8+ T cells were quantified. The study used no prisoners, and the participants were neither coerced nor paid. The manuscript was created in compliance with the Helsinki Congress and the Declaration of Istanbul. Forty-three patients tested positive for CMV antigenemia within 3 months after KT. No significant differences were found between the CMV antigenemia-positive and -negative groups in the stimulation indices for CD4+ and CD8+ T-cell responses to anti-donor stimulation. However, T-cell responses to third-party stimuli during the postoperative month 1 were significantly less in the CMV antigenemia-positive than -negative group. Anti-donor T-cell responses are not necessarily attenuated during CMV infection in KT recipients. In CMV-infected KT recipients, caution should be exercised against inadvertent dose reduction of immunosuppressants. [ABSTRACT FROM AUTHOR]

• This study demonstrated a significant inverse correlation between donor age and natural killer cell activity. • Liver-resident natural killer cells have potent antitumor activity. • Useful information was found for cell therapy in liver transplantation. Natural killer (NK) cells are involved in innate immunity and have been reported to play an important role in hepatocellular carcinoma recurrence and post-liver transplantation (LT) infection. However, the relationship between donor age and liver-resident NK cell activity remains to be elucidated. We successfully performed NK cell immunotherapy in 19 living donor LT recipients to prevent post-LT bloodstream infections. Liver mononuclear cells (LMNCs) were collected from the liver graft perfusate and stimulated with interleukin 2 for 3 days. Liver-resident NK cells were analyzed using flow cytometry and a chromium release assay before and after cell culture. The median donor age was 44 years (range, 24-64 years). The graft weight was 492 g (range, 338-642 g), and the median number of LMNCs was 584 million cells (range, 240-1472 million cells). The proportion of NK cells before and after culture was 22% and 33%, respectively. A significant correlation was found between graft weight and the number of LMNCs. However, no correlation was found between donor age and the number or percentage of NK cells in the liver. Moreover, donor age showed a significant inverse correlation with NKp46 and NKp44 expression before culture and with NKp44, tumor necrosis factor-related apoptosis-inducing ligand, and CD69 expression after culture. A significant inverse correlation was observed between donor age and NK cell activity in the liver. This information may be useful for cell therapy during LT. [ABSTRACT FROM AUTHOR]

• This retrospective study investigated the risk factors for developing metabolic syndrome components after liver transplantation. • Diabetes mellitus was associated with every component of metabolic syndrome after liver transplantation. • Preoperative abdominal aortic calcification was associated with the development of metabolic syndrome components after liver transplantation. This study aimed to assess the risk factors for components of metabolic syndrome, such as diabetes mellitus, hypertension, and dyslipidemia, more than a year after liver transplantation. This study included 164 patients with liver failure secondary to acute and chronic liver disease or hepatocellular carcinoma who underwent liver transplantation between 2000 and 2019. Univariate and multivariate analyses were performed to identify the risk factors associated with metabolic syndrome components after liver transplantation. The median follow-up period was 10.5 years. Of the 164 patients who underwent liver transplantation, 144 (87.8%) developed components of metabolic syndrome after liver transplantation. The most common cause of liver failure was hepatitis C virus infection (34.1%). The incidence of hepatocellular carcinoma was 36.0%. In univariate analysis, preoperative diabetes mellitus was a significantly more common component of metabolic syndrome than the others. In multivariate analysis, preoperative abdominal aortic calcification was a risk factor for the new onset of all components of metabolic syndrome after liver transplantation, despite the varying degree of calcification at risk of development (odds ratio for diabetes mellitus = 3.487, P =.0069; odds ratio for hypertension = 2.914, P =.0471; odds ratio for dyslipidemia = 3.553, P =.0030). Preoperative abdominal aortic calcification was significantly associated with the development of each metabolic syndrome component after liver transplantation. [ABSTRACT FROM AUTHOR]

Simple Summary: Natural killer (NK) cells have immunosurveillance potential in hepatocellular carcinoma. Human leukocyte antigen (HLA) self-recognition through killer immunoglobulin-like receptor (KIR), a process termed "licensing", raises the NK cell capacity. The polymorphic KIR-HLA genotype revealed that genetically vulnerable liver transplant recipients with a poorly licensed NK genotype have an improved prognosis by immunotherapy with donor-liver-derived NK cells. Thus, the combination of recipient and donor KIR-HLA genotypes is worthy of attention for further investigation, especially considering the clinical application of NK-cell-based immunotherapy. Natural killer (NK) cells have immunosurveillance potential in hepatocellular carcinoma (HCC). We performed adaptive immunotherapy using donor-liver-derived natural killer (NK) cells after living-donor liver transplantation (LDLT) to prevent HCC recurrence. Dominant inhibitory signals tightly regulate NK cell activity via human leukocyte antigen (HLA)-specific inhibitory receptors, such as killer immunoglobulin-like receptors (KIRs). The functional recognition of HLA through KIR raises the NK cell capacity, which is a process termed "licensing." Here, we investigated the effect of polymorphic KIR-HLA genotypes on the efficacy of NK-cell-based immunotherapy after LDLT. Seventy-seven Japanese recipients with HCC who underwent LDLT and their corresponding donors between 1996 and 2016 were enrolled in this study. The median follow-up period was 8.3 years. The HCC recurrence risk was stratified using radiological and pathological assessments according to the Milan criteria. Of the 77 recipients, 38 received immunotherapy. Immunotherapy improves early post-transplantation survival and lowers the recurrence rate in the intermediate-risk recipients. We analyzed the genotypes of five inhibitory KIRs and HLA using sequence-specific polymorphism-based typing. The polymorphic KIR-HLA genotype revealed that genetically vulnerable liver transplant recipients with a poorly licensed NK genotype have an improved prognosis by immunotherapy with donor-liver-derived NK cells. Thus, the combination of recipient and donor KIR-HLA genotypes is worthy of attention for further investigation, especially considering the clinical application of NK-cell-based immunotherapy. [ABSTRACT FROM AUTHOR]

Refractory ascites is one of the major complications of liver transplant (LT) and is associated with increased morbidity and mortality. The aim of this study was to analyze the efficacy and safety of novel cell-free and concentrated ascites reinfusion therapy (KM-CART) for the treatment of refractory ascites during preoperative living donor liver transplant. Forty KM-CART procedures were performed on 8 liver transplant candidates. We investigated the safety and efficacy of KM-CART in terms of the processed ascites, adverse events, laboratory data, and patient condition. By using KM-CART, an average of 12.5 L (range, 2.6–26.1 L) of ascites was filtered and concentrated to 0.5 L (range, 0.1–1.6 L) in 62 minutes (range, 8-187 minutes). Final products contained 21.5 g (range, 2.5–65.6 g) of albumin and 13.5 g (range, 1.5–61.8 g) of globulin. No endotoxin contamination was detected in the ascites. Although the incidence of adverse events was 35.0% (including fever, hypotension, bleeding, leg cramps, and nausea), all of these could be treated conservatively. Body weight and oral intake were significantly improved after KM-CART. Furthermore, the use of fresh frozen plasma for the LT recipients with KM-CART was significantly lower than that for patients without KM-CART. In addition, no patients lost their opportunity for LT because of adverse events due to KM-CART. Our findings show that KM-CART could be a promising option for the treatment of refractory ascites during the preoperative period of LT. This study provides the foundation for further large-scale prospective studies. [ABSTRACT FROM AUTHOR]

Background: Liver‐resident natural killer (lr‐NK) cells are distinct from conventional NK cells and exhibit higher cytotoxicity against hepatoma via tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL). However, the mechanism by which partial hepatectomy (PH) significantly suppresses TRAIL expression in lr‐NK cells remains unclear. Methods: This study aimed to investigate the PH influence on the function and characteristics of liver‐resident NK (lr‐NK) cells using a PH mouse model. Results: Here, we report that PH alters the differentiation pattern of NK cells in the liver, and an aryl hydrocarbon receptor (AhR) molecule is involved in these changes. Treatment with the AhR agonist 6‐formylindolo[3,2‐b]carbazole (FICZ) inhibited the maturation of NK cells. FICZ increased the immature subtype proportion of NK cells with high TRAIL activity and decreased the mature subtype of NK cells with low TRAIL activity. Consequently, FICZ increased the expression of TRAIL and cytotoxic activity of NK cells in the liver, and this effect was confirmed even after hepatectomy. The participation of AhR promoted FoxO1 expression in the mTOR signaling pathway involved in the maturation of NK cells, resulting in TRAIL expression. Conclusion: Our findings provide direct in‐vivo evidence that partial hepatectomy affects lrNK cell activity through NK cell differentiation in the liver. Perioperative therapies using an AhR agonist to improve NK cell function may reduce the recurrence of hepatocellular carcinoma after hepatectomy. [ABSTRACT FROM AUTHOR]

• Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is critical for natural killer cell-mediated anti-tumor and anti-microbe killing. • TRAIL expression varies between individuals and is unpredictable. • Nutrition was an independent predictive factor for low TRAIL expression. • TRAIL expression on liver natural killer cells was associated with atherosclerosis severity. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is critical for natural killer (NK) cell-mediated anti-tumor and anti-microbe killing. The TRAIL expression on the donor's liver NK cells from the liver perfusate after interleukin-2 stimulation varies between individuals and is unpredictable. This study aimed to clarify the risk factors for low TRAIL expression by analyzing perioperative donor characteristics. This retrospective study of living donor liver transplant (LDLT) donors between 2006 and 2022 was performed to analyze low TRAIL expression risk factors. Seventy-five donors who had undergone hepatectomy for LDLT were divided into 2 groups, low and high TRAIL, according to their TRAIL expression on liver NK cells, using median values. The low TRAIL group (N = 38) was older and had lower nutrition and a higher low-density lipoprotein/high-density lipoprotein (LDL/HDL) cholesterol ratio, related to arteriosclerosis, than the high TRAIL group (N = 37). In multivariate analysis, the geriatric nutritional risk index (GNRI) (odds ratio, 0.86; 95% CI, 0.76–0.94; P <.001) and LDL/HDL cholesterol ratio (odds ratio, 2.32; 95% CI, 1.10-4.86; P =.005) were independent predictive factors for low TRAIL expression on liver NK cells. Furthermore, the TRAIL expression of liver NK cells decreased in donors who already had atherosclerosis and in donors at risk of potentially developing atherosclerosis. The TRAIL expression on liver NK cells in donors had a strong relationship with atherosclerosis and GNRI. Atherosclerosis can reflect the TRAIL expression on liver NK cells. [ABSTRACT FROM AUTHOR]

Liver-resident natural killer (NK) cells express TNF-related apoptosis-inducing ligand (TRAIL), a critical molecule for NK cell-mediated tumor cell killing. We previously reported that TRAIL expression in liver NK cells decreases markedly after hepatectomy; however, the mechanism underlying this drastic alteration remains unknown. In this study, we assessed the role of chemokine signaling in liver-resident NK cells during the perioperative period of hepatectomy. The expression levels of various chemokine receptors on liver-resident NK cells and their associations with TRAIL expression were analyzed by flow cytometry. The expression of various intrahepatic chemokines/cytokines was analyzed after 70% hepatectomy in mice by quantitative RT-PCR and flow cytometry. We further investigated whether polyinosinic—polycytidylic acid (poly I:C)-induced NK cell activation could ameliorate TRAIL expression in the liver after 70% hepatectomy in CXCR3-/- and wild-type mice. TRAIL+ NK cells strongly and exclusively expressed CXCR3, and the expression of its ligand CXCL9 was significantly decreased in the liver after hepatectomy. The kinetics of hepatic CXCL9 expression resembled the changes in hepatic TRAIL+ NK cells after hepatectomy. Among liver-resident mononuclear cells, CXCL9 was predominantly secreted by macrophages in response to interferon-γ stimulation. Although the administration of poly I:C, an inducer of interferon-γ, increased hepatic CXCL9 levels in both CXCR3-/- and wild-type mice even after hepatectomy, only wild-type mice exhibited the recovery of TRAIL expression on NK cells. Partial hepatectomy remarkably reduced the proportion of TRAIL-expressing NK cells in the liver via the downregulation of the CXCL9–CXCR3 axis in mice. These findings extend our knowledge of the factors contributing to hepatocellular carcinoma recurrence after hepatectomy. [ABSTRACT FROM AUTHOR]

Cell competition is a context-dependent cell elimination via cell-cell interaction whereby unfit cells ('losers') are eliminated from the tissue when confronted with fitter cells ('winners'). Despite extensive studies, the mechanism that drives loser's death and its physiological triggers remained elusive. Here, through a genetic screen in Drosophila, we find that endoplasmic reticulum (ER) stress causes cell competition. Mechanistically, ER stress upregulates the bZIP transcription factor Xrp1, which promotes phosphorylation of the eukaryotic translation initiation factor eIF2α via the kinase PERK, leading to cell elimination. Surprisingly, our genetic data show that different cell competition triggers such as ribosomal protein mutations or RNA helicase Hel25E mutations converge on upregulation of Xrp1, which leads to phosphorylation of eIF2α and thus causes reduction in global protein synthesis and apoptosis when confronted with wild-type cells. These findings not only uncover a core pathway of cell competition but also open the way to understanding the physiological triggers of cell competition. Author summary: Cell competition is an evolutionarily conserved quality control process that selectively eliminates viable unfit cells ('losers') when coexisting with fitter cells ('winners') within a growing tissue. A common feature of loser mutants is a reduction in protein synthesis rate. Recent studies have shown that the bZIP transcription factor Xrp1 causes reduction in protein synthesis in ribosomal protein-mutant losers, while the mechanism by which Xrp1 reduces protein synthesis remained unknown. Here, through a genetic screen in Drosophila, we find that mutations causing ER stress make cells losers when surrounded by wild-type cells. Mechanistically, cells undergoing ER stress upregulate Xrp1, which promotes phosphorylation of the eukaryotic translation initiation factor eIF2α via the kinase PERK, thereby reducing global protein synthesis and inducing cell death. Crucially, this mechanism also drives cell competition triggered by ribosomal protein or Hel25E mutations, both of which cause reduction in protein synthesis rate. Our findings show that cell competition is commonly driven by Xrp1-mediated phosphorylation of eIF2α and that ER stress or other environmental stresses activating integrated stress response signaling, which converge on the phosphorylation of eIF2α, could be a physiological trigger of cell competition. [ABSTRACT FROM AUTHOR]

Gastrointestinal hormone glucagon-like peptide-1 (GLP-1) has a potent glucose-dependent insulinotropic effect and is rapidly degraded by dipeptidyl peptidase (DPP)-IV. Therefore, the use of DPP-IV inhibitors is being actively explored as a novel approach to the treatment of type 2 diabetes. The present study investigated the antidiabetic effects of the DPP-IV inhibitor ASP8497 in streptozotocin-nicotinamide-induced mildly diabetic mice which possess aggravation of glucose tolerance due to loss of early-phase insulin secretion. ASP8497 exhibited good oral bioavailability with potent inhibition of plasma DPP-IV activity. This inhibitory activity lasted up to 24 h when administered at 5 mg/kg twice a day or 10 mg/kg once a day. A single oral administration of ASP8497 (0.3–3 mg/kg) significantly improved glucose tolerance by increasing plasma insulin and GLP-1 levels during the oral glucose or liquid meal tolerance tests. These effects were seen not only immediately, but also 8 h after administration. In contrast, ASP8497 (0.3–10 mg/kg) had no significant effect on blood glucose and plasma insulin levels under fasting conditions. Furthermore, repeated administration of ASP8497 (5 mg/kg twice a day or 10 mg/kg once a day) for 25 days significantly decreased nonfasting blood glucose and HbA1c levels. These results suggest that ASP8497 is a potent and long-acting DPP-IV inhibitor that improves glucose tolerance through glucose-dependent insulinotropic action via the elevation of the GLP-1 level in streptozotocin-nicotinamide-induced mildly diabetic mice. It is expected to be useful as a therapeutic agent for impaired glucose tolerance and type 2 diabetes. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Several combination therapies have been investigated in an effort to achieve and maintain glycemic control in patients with type 2 diabetes. In this study, we combined the novel dipeptidyl peptidase (DPP)-IV inhibitor ASP8497 with the antidiabetic drugs metformin, glibenclamide, voglibose, rosiglitazone, and insulin to examine the effects of each combination on glucose tolerance in streptozotocin-nicotinamide-induced mildly diabetic mice. Single treatments with ASP8497 (1 mg/kg), metformin (300 mg/kg), glibenclamide (3 mg/kg), voglibose (0.3 mg/kg), rosiglitazone (10 mg/kg), or insulin (0.2 IU/kg) significantly improved glucose tolerance during the liquid meal tolerance test. In addition, combination treatment with ASP8497 and each antidiabetic drug additively improved glucose tolerance. Among these, the combination of ASP8497 and glibenclamide or insulin additively ameliorated glucose tolerance with an additive increase in the plasma insulin level; however, it did not affect the fasting blood glucose lowering effects of glibenclamide or insulin. These profiles indicate that the combination of ASP8497 with existing antidiabetic drugs could be useful for correcting the postprandial hyperglycemia seen with type 2 diabetes. [Copyright &y& Elsevier]

In this study, streptozotocin-induced severely diabetic rats and streptozotocin-nicotinamide-induced mildly diabetic rats were established to compare their characteristics and to investigate the hypoglycaemic effects of antidiabetic drugs. Results show that in streptozotocin-induced severely diabetic rats, the pancreatic insulin content decreased to approximately 10% of that in normal rats. These severely diabetic rats also exhibited marked hyperglycaemia and impaired glucose tolerance due to insulin secretory deficiency. In contrast, the pancreatic insulin content was approximately 50% of normal levels in streptozotocin-nicotinamide-induced mildly diabetic rats. These mildly diabetic rats exhibited moderate hyperglycaemia and impaired glucose tolerance due to loss of early-phase insulin secretion. Voglibose (α-glucosidase inhibitor), metformin (biguanide), glibenclamide (sulfonylurea), sitagliptin (dipeptidyl peptidase-4 inhibitor) and insulin significantly improved glucose tolerance in streptozotocin-nicotinamide-induced mildly diabetic rats. In contrast, in streptozotocin-induced severely diabetic rats, voglibose, metformin and insulin significantly improved glucose tolerance, but no significant effect was observed for glibenclamide and sitagliptin due to a decreased insulinotropic effect. These results suggest that streptozotocin-nicotinamide-induced mildly diabetic rats, which exhibit a mild decline in glucose tolerance due to loss of early-phase insulin secretion, are sensitive to the hypoglycaemic effects of insulinotropic agents and have many pathological features resembling type 2 diabetes, which may be useful in the pharmacological investigation of numerous antidiabetic drugs. [ABSTRACT FROM AUTHOR]

Abstract: Dipeptidyl peptidase (DPP)-IV inhibitors are expected to become a useful new class of antidiabetic agent. The aim of the present study is to characterize the in vitro and in vivo profile of ASP8497, (2S,4S)-4-fluoro-1-({[4-methyl-1-(methylsulfonyl)piperidin-4-yl]amino}acetyl)pyrrolidine-2-carbonitrile monofumarate, which is a novel DPP-IV inhibitor. ASP8497 inhibited DPP-IV in plasma from mice, rats, dogs and humans with IC50 values of 3.86, 2.36, 5.53 and 5.30nM, respectively. In contrast, ASP8497 did not potently inhibit DPP8 or DPP9 activity (IC50 >200nM). Kinetic analysis indicated that ASP8497 inhibits DPP-IV activity in a competitive manner. In streptozotocin–nicotinamide-induced diabetic mice, ASP8497 (3mg/kg) significantly reduced glucose excursion during the oral glucose tolerance test conducted 0.5 and 8.5h after administration, with increases in plasma insulin and active glucagon-like peptide-1 (GLP-1) levels. In contrast, ASP8497 (3 and 30mg/kg) did not cause hypoglycemia in fasted normal mice. Furthermore, administration of exogenous GLP-1 induced significant inhibition of gastric emptying and small intestinal transit rates, but ASP8497 (30mg/kg) had no significant effects in normal mice. These present preclinical studies indicate that ASP8497 is a novel selective DPP-IV inhibitor with long-acting antidiabetic effect that might be a potential agent for type 2 diabetes. [Copyright &y& Elsevier]

Nucleosome assembly protein 1 (Nap1) is widely conserved from yeasts to humans and facilitates nucleosome formation in vitro as a histone chaperone. Nap1 is generally localized in the cytoplasm, except that subcellular localization of Drosophila melanogaster Nap1 is dynamically regulated between the cytoplasm and nucleus during early development. The cytoplasmic localization of Nap1 is seemingly incompatible with the proposed role of Nap1 in nucleosome formation, which should occur in the nucleus. Here, we have examined the roles of a putative nuclear export signal (NES) sequence in yeast Nap1 (yNap1). yNap1 mutants lacking the NES-like sequence were localized predominantly in the nucleus. Deletion of NAP1 in cells harboring a single mitotic cyclin gene is known to cause mitotic delay and temperature-sensitive growth. A wild-type NAP1 complemented these phenotypes while nap1 mutant genes lacking the NES-like sequence or carboxy-terminal region did not. These and other results suggest that yNap1 is a nucleocytoplasmic shuttling protein and that its shuttling is important for yNap1 function during mitotic progression. This study also provides a possible explanation for Nap1's involvement in nucleosome assembly and/or remodeling in the nucleus. [ABSTRACT FROM AUTHOR]

G-protein coupled receptors (GPCRs) are known for their low stability and large conformational changes upon transitions between multiple states. A widely used method for stabilizing these receptors is to make chimeric receptors by fusing soluble proteins (i.e., fusion partner proteins) into the intracellular loop 3 (ICL3) connecting the transmembrane helices 5 and 6 (TM5 and TM6). However, this fusion approach requires experimental trial and error to identify appropriate soluble proteins, residue positions, and linker lengths for making the fusion. Moreover, this approach has not provided state-targeting stabilization of GPCRs. Here, to rationally stabilize a class A GPCR, adenosine A2A receptor (A2AR) in a target state, we carried out the custom-made de novo design of α-helical fusion partner proteins, which can fix the conformation of TM5 and TM6 to that in an inactive state of A2AR through straight helical connections without any kinks or intervening loops. The chimeric A2AR fused with one of the designs (FiX1) exhibited increased thermal stability. Moreover, compared with the wild type, the binding affinity of the chimera against the agonist NECA was significantly decreased, whereas that against the inverse agonist ZM241385 was similar, indicating that the inactive state was selectively stabilized. Our strategy contributes to the rational state-targeting stabilization of GPCRs. [ABSTRACT FROM AUTHOR]

Influenza viruses infect vertebrates, including mammals and birds. Influenza virus reverse-genetics systems facilitate the study of the structure and function of viral factors. In contrast, less is known about host factors involved in the replication process. Here, we developed a replication and transcription system of the negative- strand RNA genome of the influenza virus in Saccharomyces cerevisiae, which depends on viral RNA5, viral RNA polymerases, and nucleoprotein (NP). Disruption of SUB2 encoding an orthologue of human RAF-2p48/UAP56, a previously identified viral RNA synthesis stimulatory host factor, resulted in reduction of the viral RNA synthesis rate. Using a genome-wide set of yeast single-gene deletion strains, we found several host factor candidates affecting viral RNA synthesis. We found that among them, Tat-SF1, a mammalian homologue of yeast CUS2. was a stimulatory host factor in influenza virus RNA synthesis. Tat-SF1 interacted with free NP, but not with NP associated with RNA, and facilitated formation of RNA-NP complexes. These results suggest that Tat-SF1 may function as a molecular chaperone for NP, as does RAF-2p48/UAP56. This system has proven useful for further studies on the mechanism of influenza virus genome replication and transcription. [ABSTRACT FROM AUTHOR]

To investigate the role of insulin receptor substrate (IRS)-2 in vivo, we generated IRS-2-deficient mice by gene targeting. Although homozygous IRS-2-deficient mice (IRS-2-/- mice) had a body weight similar to wild-type mice, they progressively developed type 2 diabetes at 10 weeks. IRS-2-/- mice showed insulin resistance and a defect in the insulin-stimulated signaling pathway in liver but not in skeletal muscle. Despite insulin resistance, the amount of beta-cells was reduced to 83% of that in wild-type mice, which was in marked contrast to the 85% increase in the amount of beta-cells in IRS-1-deficient mice (IRS-1-/- mice) to compensate for insulin resistance. Thus, IRS-2 plays a crucial role in the regulation of beta-cell mass. On the other hand, insulin secretion by the same number of cells in response to glucose measured ex vivo was significantly increased in IRS-2-/- mice compared with wild-type mice but was decreased in IRS-1-/- mice. These results suggest that IRS-1 and IRS-2 may play different roles in the regulation of beta-cell mass and the function of individual beta-cells. [ABSTRACT FROM AUTHOR]

R3261 --> The novel type of silica nanoparticles, organosilica nanoparticles, has been developed by Nakamura and colleagues. The nanoparticles can be synthesized in a few of simple reactions and have a good size and dispersibility. Organosilica nanoparticles have SH groups on their surface, which makes it possible to conjugate them with antibodies and other protein molecules. We synthesized organosilica nanoparticles with a diameter of 100 nm, containing fluorescein isothiocyanate (FITC) or Rhodamine B, which resulted in high fluorescence intensity. These nanoparticles were tested in various biochemical applications and in this study, we focused on their use in flow cytometry. We found that the application of these nanoparticles with antibodies could efficiently detect specific cells in a flow cytometer. We also discuss cell tracking methods using these nanoparticles. [ABSTRACT FROM AUTHOR]