Detection of New H5N1 High Pathogenicity Avian Influenza Viruses in Winter 2021–2022 in the Far East,Which Are Genetically Close to Those in Europe

Many high pathogenicity avian influenza (HPAI) cases in wild birds due to H5N1 HPAI virus (HPAIV) infection were reported in northern Japan in the winter of 2021–2022. To investigate the epidemiology of HPAIVs brought to Japan from surrounding areas, a genetic analysis of H5 HPAIVs isolated in northern Japan was performed, and the pathogenicity of the HPAIV in chickens was assessed by experimental infection. Based on the genetic analysis of the hemagglutinin gene, pathogenic viruses detected in northern Japan as well as one in Sakhalin, the eastern part of Russia, were classified into the same subgroup as viruses prevalent in Europe in the same season but distinct from those circulating in Asia in winter 2020–2021. High identities of all eight segment sequences of A/crow/Hokkaido/0103B065/2022 (H5N1) (Crow/Hok), the representative isolates in northern Japan in 2022, to European isolates in the same season could also certify the unlikeliness of causing gene reassortment between H5 HPAIVs and viruses locally circulating in Asia. According to intranasal challenge results in six-week-old chickens, 50% of the chicken-lethal dose of Crow/Hok was calculated as 10^4.5 times of the 50% egg-infectious dose. These results demonstrated that the currently prevalent H5 HPAIVs could spread widely from certain origins throughout the Eurasian continent, including Europe and the Far East, and implied a possibility that contagious viruses are gathered in lakes in the northern territory via bird migration. Active monitoring of wild birds at the global level is essential to estimate the geographical source and spread dynamics of HPAIVs.     

Single Nucleotide Variants of the Human TIM-1 IgV Domain with Reduced Ability to Promote Viral Entry into Cells

Human T-cell immunoglobulin mucin 1 (hTIM-1) is known to promote cellular entry of enveloped viruses. Previous studies suggested that the polymorphisms of hTIM-1 affected its function. Here, we analyzed single nucleotide variants (SNVs) of hTIM-1 to determine their ability to promote cellular entry of viruses using pseudotyped vesicular stomatitis Indiana virus (VSIV). We obtained hTIM-1 sequences from a public database (Ensembl genome browser) and identified 35 missense SNVs in 3 loops of the hTIM-1 immunoglobulin variable (IgV) domain, which had been reported to interact with the Ebola virus glycoprotein (GP) and phosphatidylserine (PS) in the viral envelope. HEK293T cells transiently expressing wildtype hTIM-1 or its SNV mutants were infected with VSIVs pseudotyped with filovirus or arenavirus GPs, and their infectivities were compared. Eleven of the thirty-five SNV substitutions reduced the efficiency of hTIM-1-mediated entry of pseudotyped VSIVs. These SNV substitutions were found not only around the PS-binding pocket but also in other regions of the molecule. Taken together, our findings suggest that some SNVs of the hTIM-1 IgV domain have impaired ability to interact with PS and/or viral GPs in the viral envelope, which may affect the hTIM-1 function to promote viral entry into cells.     

Intraoperative determination of the risky angles and safe distances for preventing deep femoral artery injury during proximal femoral nailing for hip fractures in Asian people

Objective:During proximal femoral nailing, deep femoral artery injury, a rare condition, is often missed and found late, leading to intractable complications such as false aneurysm, hematoma, and anemia. We aimed to determine the novel indicators of the high-risk vertical range and axial angle for deep femoral artery injury that can be easily confirmed intraoperatively using fluoroscopy for hip fracture.Methods:In a single hospital, the lower extremity computed tomography angiographies of 88 patients (50 men and 38 women) were analyzed. A reference plane was defined as the femoral neck and shaft on the same straight line in the lateral view. Reference points were the lower end of the lesser trochanter and distal femur at 140 mm from the tip of the greater trochanter. To determine the high-risk angle for deep femoral artery injury based on the reference plane, the angle from the reference plane to the deep femoral artery (bone–arterial angle) and the shortest distance between the surfaces of the femur and the deep femoral artery (bone–artery distance) were measured at the lesser trochanter and the greater trochanter. We analyzed the bone–arterial angle and bone–artery distance values, their differences among the sexes, and their correlation with body height and body weight.Results:Overall, in the lesser trochanter, the mean bone–arterial angle and bone–artery distance were 19.2° ± 8.0° and 22.9 ± 4.7 mm, respectively. In the greater trochanter, the mean bone–arterial angle and bone–artery distance were –33.9° ± 17.0° and 11.3 ± 4.1 mm, respectively. The mean bone–artery distance of the lesser trochanter was significantly longer in men than in women (24.1 ± 4.5 mm and 21.4 ± 4.5 mm, respectively, P < 0.01), and for the lesser trochanter, positive correlations were found between body height and both bone–arterial angle and bone–artery distance (r = 0.373, P < 0.001; and r = 0.456, P < 0.0001, respectively), with body weight and bone–artery distance positively correlated (r = 0.367, P < 0.001). At the greater trochanter, there were negative correlations between body height and bone–arterial angle (r = –0.5671, P < 0.0001), body weight, and bone–arterial angle (r = –0.338, P < 0.01).Conclusion:The knowledge of our reference plane and high-risk angles and distances allows surgeons to minimize the risk of deep femoral artery injury. These are easily confirmed intraoperatively using fluoroscopy, allowing surgeons to avoid maneuvering in the deep femoral artery range.Level of Evidence:Level IV, Diagnostic Study     

Phase I Study of Tremelimumab Monotherapy or in Combination With Durvalumab in Japanese Patients With Advanced Solid Tumors or Malignant Mesothelioma

BackgroundThe primary objective of this phase I, open-label trial was to assess safety and tolerability of tremelimumab monotherapy and combination therapy with durvalumab in Japanese patients with advanced cancer. Tremelimumab is a fully human monoclonal antibody against CTLA-4 in clinical trials; durvalumab is a monoclonal antibody against PD-L1 for the treatment of bladder and lung cancer.MethodsIn part 1, tremelimumab 3 or 10 mg/kg was given every 4 weeks (Q4W) for 6 doses, and thereafter every 12 weeks until discontinuation (n = 8); subsequently tremelimumab 10 mg/kg Q4W for 6 doses/Q12W and thereafter until discontinuation was administered in 41 patients with malignant pleural or peritoneal mesothelioma (MPM). In part 2, tremelimumab 10 mg/kg (Q4W for 6 doses followed by Q12W for 3 doses) was given in combination with durvalumab 15 mg/kg (Q4W for 13 doses) in cohort 1 (n = 4). In cohort 2 (n = 6), tremelimumab 1 mg/kg (Q4W for 4 doses) was given in combination with durvalumab 20 mg/kg (Q4W for 4 doses followed by 10 mg/kg Q2W for 22 doses), while in cohort 3 (n = 6), fixed-dose tremelimumab 75 mg Q4W for 4 doses plus durvalumab 1500 mg Q4W for 13 doses was given.ResultsIn part 1, no dose-limiting toxicities (DLTs) for tremelimumab 3 or 10 mg/kg (Q4W for 6 doses/Q12W thereafter until discontinuation) were observed. Six (75%) patients reported treatment-related adverse events (trAEs). In the MPM dose-expansion cohort, 38 (92.7%) patients reported trAEs. In part 2, one DLT (Grade 4 myasthenia gravis) was reported for tremelimumab 10 mg/kg (Q4W for 6 doses/Q12W for 3 doses) plus durvalumab 15 mg/kg (Q4W for 13 doses). One DLT (Grade 4 hyperglycemia) was reported for tremelimumab 75 mg (Q4W for 4 doses) plus durvalumab 1500 mg (Q4W for 13 doses). Fourteen (87.5%) patients reported trAEs. Tremelimumab demonstrated low immunogenicity; 1 (16.7%) patient developed antidrug antibodies.ConclusionTremelimumab 10 mg/kg (Q4W/Q12W), tremelimumab 1 mg/kg (Q4W) plus durvalumab 20 mg/kg (Q4W/10 mg/kg Q2W), and fixed-dose tremelimumab 75 mg (Q4W) plus durvalumab 1500 mg (Q4W) were safe and tolerable.ClinicalTrials.gov Identifier: {"type":"clinical-trial","attrs":{"text":"NCT02141347","term_id":"NCT02141347"}}NCT02141347 (https://clinicaltrials.gov/ct2/show/{"type":"clinical-trial","attrs":{"text":"NCT02141347","term_id":"NCT02141347"}}NCT02141347)     

Genetic variations and haplotype structures of the ABC transporter gene ABCC1 in a Japanese population

Multidrug resistance-related protein 1 (MRP1), an ATP-binding cassette transporter encoded by the ABCC1 gene, is expressed in many tissues, and functions as an efflux transporter for glutathione-, glucuronate- and sulfate-conjugates as well as unconjugated substrates. In this study, the 31 exons and their flanking introns of ABCC1 were comprehensively screened for genetic variations in 153 Japanese subjects to elucidate the linkage disequilibrium (LD) profiles and haplotype structures of ABCC1 that is necessary for pharmacogenetic studies of the substrate drugs. Eighty-six genetic variations including 31 novel ones were found: 1 in the 5'-flanking region, 1 in the 5'-untranslated region (UTR), 20 in the coding exons (9 synonymous and 11 nonsynonymous variations), 4 in the 3'-UTR, and 60 in the introns. Of these, eight novel nonsynonymous variations, 726G>T (Trp242Cys), 1199T>C (Ile400Thr), 1967G>C (Ser656Thr), 2530G>A (Gly844Ser), 3490G>A (Val1164Ile), 3550G>A (Glu1184Lys), 3901C>T (Arg1301Cys), and 4502A>G (Asp1501Gly), were detected with an allele frequency of 0.003. Based on the LD profiles, the analyzed regions of the gene were divided into five LD blocks (Blocks -1 and 1 to 4). The multiallelic repeat polymorphism in the 5'-UTR was defined as Block -1. For Blocks 1, 2, 3 and 4, 32, 23, 23 and 13 haplotypes were inferred, and 9, 7, 7 and 6 haplotypes commonly found on > or = 10 chromosomes accounted for > or = 91% of the inferred haplotypes in each block. Haplotype-tagging single nucleotide polymorphisms for each block were identified to capture the common haplotypes. This study would provide fundamental and useful information for the pharmacogenetic studies of MRP1-dependently effluxed drugs in Japanese.     

A novel hepatic-targeting system for therapeutic cytokines that delivers to the hepatic asialoglycoprotein receptor,but avoids receptor-mediated endocytosis

Purpose. To demonstrate the utilities of a synthetic low-affinity ligand ((Gal)₃) for the asialoglycoprotein receptor (ASGP-R) as a hepatic targeting device for therapeutic cytokines. Methods. The site-specific incorporation of (Gal)₃ or a typical high-affinity ligand (GalNAc)₃ into IL-2 was catalyzed by microbial transglutaminase. The anti-tumor activities, pharmacokinetic profiles and receptor-mediated endocytosis in hepatocytes of the ligand-IL-2 conjugates were examined in mouse. Results. The (Gal)₃ has approximately 50 times lower affinity to ASGP-R than (GalNAc)₃. Nevertheless, the antitumor effects were in the order of (Gal)₃—IL-2 > unmodified IL-2 > (GalNAc)₃—IL-2. The systemic elimination and the hepatic uptake of (GalNAc)₃—IL-2 were more rapid than (Gal)₃—IL-2. The ratio of the rate constant representing dissociation from the cell-surface receptor (k_off) to that representing endocytosis of the ligand (k_int) was greater for (Gal)₃—IL-2 than (GalNAc)₃—IL-2, suggesting that (Gal)₃—IL-2 preferably avoids internalization due to its lower affinity to the receptor. The simulation studies demonstrated that (Gal)₃—IL-2 was present in the hepatic extracellular space for a longer period than (GalNAc)₃ IL-2. Conclusions. The (Gal)₃ ligand increases the therapeutic efficacy of IL-2 by enhancing its exposure to the cell-surface. The k_off/k_int affects the targeting efficacy of the conjugates to ASGP-R.     

Successful Treatment of Nephrotic Syndrome Due to Collapsing Focal Segmental Glomerulosclerosis Accompanied by Acute Interstitial Nephritis

A 39-year-old woman was hospitalized for nephrotic syndrome. Laboratory test results showed increased serum creatinine levels and urinary excretions of beta-2-microglobulin, and N-acetyl-beta-D-glucosaminidase. A renal biopsy revealed collapsing focal segmental glomerulosclerosis (FSGS) and acute interstitial nephritis. Despite treatment with pulse steroid followed by oral high-dose glucocorticoids and cyclosporines, heavy proteinuria persisted. After low-density lipoprotein apheresis (LDL-A) therapy was initiated, her proteinuria gradually decreased, leading to complete remission. A repeat renal biopsy after treatment revealed no collapsing glomeruli. Immediate LDL-A should be performed to treat cases of collapsing FSGS poorly responding to other treatments.