The Broad-Complex gene (BR-C) encodes transcription factors that dictate larval-pupal metamorphosis in insects. The expression of BR-C is induced by molting hormone (20-hydroxyecdysone (20E)), and this induction is repressed by juvenile hormone (JH), which exists during the premature larval stage. Krüppel homolog 1 gene (Kr-h1) has been known as a JH-early inducible gene responsible for repression of metamorphosis; however, the functional relationship between Kr-h1 and repression of BR-C has remained unclear. To elucidate this relationship, we analyzed cis-and trans elements involved in the repression of BR-C using a Bombyx mori cell line. In the cells, as observed in larvae, JH induced the expression of Kr-h1 and concurrently suppressed 20E-induced expression of BR-C. Forced expression of Kr-h1 repressed the 20E-dependent activation of the BR-C promoter in the absence of JH, and Kr-h1 RNAi inhibited the JH-mediated repression, suggesting that Kr-h1 controlled the repression of BR-C. A survey of the upstream sequence of BR-C gene revealed a Kr-h1 binding site (KBS) in the BR-C promoter. When KBS was deleted from the promoter, the repression of BR-C was abolished. Electrophoresis mobility shift demonstrated that two Kr-h1 molecules bound to KBS in the BR-C promoter. Based on these results, we conclude that Kr-h1 protein molecules directly bind to the KBS sequence in the BR-C promoter and thereby repress 20E-dependent activation of the pupal specifier, BR-C. This study has revealed a considerable portion of the picture of JH signaling pathways from the reception of JH to the repression of metamorphosis.The molting and metamorphosis of insects are intricately regulated by the actions and interactions of ecdysteroids and juvenile hormone (JH).2 In holometabolous insects, 20-hydroxyecdysone (20E, the primary active ecdysteroid) induces the larval-larval molt in the presence of JH. When the JH titer declines to a trace level in the final larval instar, 20E induces larval-pupal and pupal-adult molts (metamorphosis). Thus, JH plays a key role in preventing larvae from undergoing precocious metamorphosis (1).Our understanding of the molecular mechanism of JH-mediated repression of insect metamorphosis has significantly advanced (2): JH carried to a target cell is received by a JH receptor, methoprene tolerant (Met) (3-6); JH-liganded Met interacts with steroid receptor coactivator (7-12); the JH/Met/ steroid receptor coactivator complex activates Krüppel homolog 1 (Kr-h1), a repressor of metamorphosis, by interacting with a JH response element (kJHRE) in the Kr-h1 gene (9, 10, 12-15); Kr-h1 represses the larval-pupal metamorphosis (16 -20). To date, however, the mechanism of the repression of metamorphosis by Kr-h1, including target gene(s), binding site(s), and partner(s), has remained unknown.The Broad-Complex (BR-C) protein is a transcription factor that is composed of a Bric-a-brac/Tramtrack/Broad-Complex (BTB) domain and an alternatively spliced zinc finger domain (Z1-Z6) (21-25). BR-C expression is induced by 20E, ...
The diagnosis of primary immune thrombocytopenia (ITP) is based on differential diagnosis. Although the measurement of percentages of reticulated platelets (RP%) by flow cytometry is useful as a supportive diagnostic test, this method is nonetheless a time-consuming, laboratory-based assay. To identify alternative assays that are useful in daily practice, we compared three methods in parallel, IPF% measured by XE-2100 [IPF% (XE), Sysmex Corp.], IPF% measured by new XN-1000 [IPF% (XN)], and RP%. We examined 47 patients with primary ITP, 28 patients with aplastic thrombocytopenia (18 aplastic anemia and 10 chemotherapy-induced thrombocytopenia) and 80 healthy controls. In a selected experiment, we examined 16 patients with paroxysmal nocturnal hemoglobinuria (PNH) to examine the effect of hemolysis. As compared with IPF% (XE), IPF% (XN) showed better within-run reproducibility. The sensitivity and specificity for the diagnosis of ITP were 83.0 and 75.0 % for IPF% (XE), 85.1 and 89.3 % for IPF% (XN), and 93.6 and 89.3 % for RP%, respectively. Examination of PNH patients revealed that hemolysis and/or red blood cell fragments interfered with IPF% (XE) values, but not with IFP % (XN) values. Our results suggest that IPF% measured by XN-1000 may be of comparable value with RP% as a supportive diagnostic test for ITP.
Although recently published case reports suggest the significance of Jr(a) alloimmunization in the obstetric setting, the involved mechanism still remains unclear. Here we report a case of severe fetal and neonatal anemia associated with anti-Jr(a) alloimmunization, which was successfully managed using Doppler assessment of peak systolic velocity of the fetal middle cerebral artery (MCA-PSV). A Japanese woman with anti-Jr(a) (titer 1024) was referred to our department at 20 weeks' gestation. As fetal MCA-PSV exceeded 1.5 multiple of median, labor was induced and a female neonate of 1998 g was delivered vaginally at 33 weeks and 5 days of gestation. The infant's hematocrit and hemoglobin levels were 25.4% and 82 g/L, respectively, but her total bilirubin level (15 µmol/L; 0.9 mg/dL) and reticulocyte counts (4.5%) were low. During the course, the infant showed no apparent signs of hemolysis. Jr(a) alloimmunization should be recognized as a possible cause of fetal anemia with no direct hemolytic process.
BACKGROUND: There is an increasing demand for daratumumab (DARA), an immunoglobulin (Ig)G1κ monoclonal antibody (MoAb) that recognizes CD38, to manage relapsed or refractory multiple myeloma (MM) patients. However, DARA leads to positive and panreactive agglutination reactions in indirect antiglobulin tests (IATs) in vitro (the DARA interference). In addition, effects of DARA on red blood cells (RBCs) in vivo remains elusive. STUDY DESIGN AND METHODS:To develop a new method to negate the DARA interference, the effects of various concentrations of dithiothreitol (DTT) on RBC CD38 and Kell antigenicity in combination with an automatic blood cell washing centrifuge were compared with the AABB standard procedure in parallel. Moreover, direct antiglobulin tests (DATs) for RBCs in DARAtreated MM patients were examined. RESULTS:A quantity of 0.01 mol/L DTT as well as the AABB procedure (equivalent to 0.15 mol/L DTT in our procedure) markedly reduced the reactivity of phycoerythrin-mouse anti-CD38 MoAb and DARA with RBCs. In sharp contrast to the AABB procedure, 0.01 mol/L DTT partially preserved K antigenicity and allowed the determination of phenotype of K antigen even in the presence of the DARA interference. In contrast, DAT for RBCs obtained from MM patients showed a weak positive or negative reaction. Immunoblotting further indicated that DARA induced loss of CD38 in vivo. CONCLUSION:A simple and reliable method to negate the DARA interference with partially preserving Kell antigenicity is proposed (Osaka method). CD38 antigenicity is susceptible to 0.01 mol/L DTT treatment even in the presence of DARA. Our data also demonstrate distinct effects of DARA on IAT in vitro and DAT in vivo. ABBREVIATIONS: DARA = daratumumab; MM = multiple myeloma. From the Volume 58, December 2018 TRANSFUSION 3003 † †p < 0.01, † † †p < 0.001. (D) Amounts of specific binding of PE-mouse anti-human CD38 MoAb are shown as MFI (mean AE SD).
Insecticide resistance has recently become a serious problem in the agricultural field. Development of insecticides with new mechanisms of action is essential to overcome this limitation. Juvenile hormone (JH) is an insect-specific hormone that plays key roles in maintaining the larval stage of insects. Hence, JH signaling pathway is considered a suitable target in the development of novel insecticides; however, only a few JH signaling inhibitors (JHSIs) have been reported, and no practical JHSIs have been developed. Here, we established a high-throughput screening (HTS) system for exploration of novel JHSIs using a Bombyx mori cell line (BmN_JF&AR cells) and carried out a large-scale screening in this cell line using a chemical library. The four-step HTS yielded 69 compounds as candidate JHSIs. Topical application of JHSI48 to B. mori larvae caused precocious metamorphosis. In ex vivo culture of the epidermis, JHSI48 suppressed the expression of the Krüppel homolog 1 gene, which is directly activated by JH-liganded receptor. Moreover, JHSI48 caused a parallel rightward shift in the JH response curve, suggesting that JHSI48 possesses a competitive antagonist-like activity. Thus, large-scale HTS using chemical libraries may have applications in development of future insecticides targeting the JH signaling pathway.
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