Age‐ and sex‐associated morphological variations of metatarsal torsional patterns in humans

It has been demonstrated that the torsional patterns of the metatarsal heads are associated with the presence or absence of the medial longitudinal arch in hominoid feet. The relatively untwisted second metatarsal is unique in humans, but that of the African apes is much more inverted, suggesting that the torsion of the second metatarsal might represent the overall shape and flatness of the foot. Some clinical studies have recently argued that the onset of foot pathologies such as hallux valgus might be related to the torsional pattern of the metatarsals. However, to date, no studies have systematically investigated the morphological variations of the torsional patterns of human metatarsals. In this study, therefore, the aim was to clarify the age‐ and sex‐associated variations in the torsional patterns of human metatarsals using three‐dimensional computed tomography. The torsion angles of the five metatarsals were calculated by defining the dorsopalmar vector of the metatarsal base and the vector corresponding to the rotational axis of the metatarsal head. The present result demonstrated that the second metatarsals of females were significantly more inverted with increasing age. Flat foot is known to be most common in elderly women. Whether there is a cause–effect relationship between second metatarsal torsion and flattening of the medial longitudinal arch has yet to be answered, but this study suggested that torsion of the second metatarsal might possibly be used as an indicator for the early diagnosis of flat foot and associated foot pathologies. Clin. Anat. 30:1058–1063, 2017. © 2017 Wiley Periodicals, Inc.     

Polyurea With L‐Lysinyl Residues as Components: Application to Membrane Separation of Enantiomers

Novel polyureas are synthesized from lysinyl residues. The polyurea thus prepared yields a durable self‐standing membrane that can be converted into a molecular recognition material by using Z‐D ‐Glu or Z‐L ‐Glu as a print molecule. The Z‐D ‐Glu molecularly imprinted membrane adsorbes the D ‐isomer of Glu in preference to the corresponding L ‐Glu and vice versa. Even though the polyurea consists of L ‐lysinyl residues, both Z‐D ‐Glu and Z‐L ‐Glu work as print molecules to construct molecular (chiral) recognition sites in the membrane. Those molecularly imprinted membranes show chiral separation abilities when a concentration gradient or an applied potential difference is applied as a driving force for membrane transport.

     

Rapid B cell apoptosis induced by antigen receptor ligation does not require Fas (CD95/APO-1), the adaptor protein FADD/MORT1 or CrmA-sensitive caspases but is defective in both MRL-+/+ and MRL-lpr/lpr mice

Antigen receptor ligation-induced apoptosis is thought to play a role in self-tolerance by deleting autoreactive lymphocytes. Antigen receptor ligation-induced apoptosis of mature T cells and T cell lines requires autocrine or paracrine activation of Fas (CD95/APO-1). Whether B cell antigen receptor (BCR)-mediated apoptosis requires Fas or related molecules is unclear. Here we demonstrate that expression of either CrmA, the cowpox virus serpin, or an inhibitor of the adapter protein FADD/MORT1 blocks Fas-mediated apoptosis but has no effect on BCR ligation-induced apoptosis of the B cell line WEHI-231. In contrast, expression of Bcl-2 blocks BCR-mediated but not Fas-induced apoptosis in WEHI-231 cells. These results indicate that BCR ligation activates an apoptotic signaling pathway distinct from Fas-mediated apoptosis in WEHI-231 cells, and that BCR-mediated apoptosis of WEHI-231 cells does not require Fas or related molecules such as DR3, DR4 and DR5, as all of these death receptors require FADD/MORT1 and/or CrmA-sensitive caspases for induction of apoptosis. Moreover, extensive BCR ligation induces death of mature B cells from C57BL/6-lpr/lpr mice as efficiently as those from C57BL/6 mice, indicating that Fas is not essential for BCR-mediated apoptosis of mature B cells. In contrast, BCR ligation-induced apoptosis is reduced in mature B cells from MRL mice and this is not affected by the lpr mutation. Since MRL-lpr/lpr mice but not C57BL/6-lpr/lpr mice develop severe autoimmune disease, defects in BCR-mediated apoptosis in the MRL background, together with lpr mutation, may contribute to the development of severe autoimmune disease in MRL-lpr/lpr mice by allowing survival of self-reactive B cells.     

Tissue factor pathway inhibitor can interact with platelets

Tissue factor pathway inhibitor (TFPI) regulates the extrinsic pathway of blood coagulation. However, there is no report on interaction between TFPI and platelets other than that by Tsuji, who found that whole blood anticoagulated with TFPI exhibited remarkable decrease in platelet count. Our study revealed that washed platelets suspended in modified Tyrode's buffer (8 mM CaCl2) containing TFPI exhibit platelet aggregation. However, platelets aggregation was observed without TFPI, but its increase and intensity were slow and weak, compared to that in the presence of TFPI. This aggregation was inhibited by anti-CD41 (anti-GPIIb) antibody. This finding suggested that TFPI promotes platelet aggregation.     

Regulatory T cells for tolerance

Regulatory T cells (Tregs) are critical mediators of immune homeostasis and hold significant promise in the quest for transplantation tolerance. Progress has now reached a critical threshold as techniques for production of clinical therapies are optimised and Phase I/II clinical trials are in full swing. Initial safety and efficacy data are being reported, with trials assessing a number of different strategies for the introduction of Treg therapy. It is now more crucial than ever to elucidate further the function and behaviour of Tregs in vivo and ensure safe delivery. This review will discuss the current state of the art and future directions in Treg therapy.     

A novel de novo point mutation of the OCT‐binding site in the IGF2/H19‐imprinting control region in a Beckwith–Wiedemann syndrome patient

The IGF2/H19‐imprinting control region (ICR1) functions as an insulator to methylation‐sensitive binding of CTCF protein, and regulates imprinted expression of IGF2 and H19 in a parental origin‐specific manner. ICR1 methylation defects cause abnormal expression of imprinted genes, leading to Beckwith–Wiedemann syndrome (BWS) or Silver–Russell syndrome (SRS). Not only ICR1 microdeletions involving the CTCF‐binding site, but also point mutations and a small deletion of the OCT‐binding site have been shown to trigger methylation defects in BWS. Here, mutational analysis of ICR1 in 11 BWS and 12 SRS patients with ICR1 methylation defects revealed a novel de novo point mutation of the OCT‐binding site on the maternal allele in one BWS patient. In BWS, all reported mutations and the small deletion of the OCT‐binding site, including our case, have occurred within repeat A2. These findings indicate that the OCT‐binding site is important for maintaining an unmethylated status of maternal ICR1 in early embryogenesis.     

Radiation-induced reactive oxygen species formation prior to oxidative DNA damage in human peripheral T cells

Previously, we demonstrated that human peripheral T lymphocytes revealed early apoptotic changes (annexin V-positive) and late apoptotic changes (propidium iodide-positive), at 13 and 24 h, respectively, after irradiation of 5 Gy. Changes in mitochondrial membrane potential were observed at 10 h after irradiation of 5 Gy. Subsequently, mitochondrial cytochrome c-release was confirmed. In order to elucidate the mechanism which acts prior to the mitochondrial membrane potential changes, we examined in the previous study the radiation dose and the timing of oxidative DNA damage induced in human peripheral T lymphocytes following 10 MV X-ray irradiation. As a result, the production of 8-oxoguanine, i.e., the product of oxidative DNA damage, was clearly identified starting at 10, 6, and 3 h, after 2, 5, and 20 Gy of irradiation, respectively. Therefore, we examined in the present study reactive oxygen species (ROS) formation in T lymphocytes following 5 Gy of irradiation. Using a CCD camera system, we monitored fluorescence in T lymphocytes loaded with the succinimidyl ester of dichlorodihydrofluorescein diacetate (H2DCFDA), which is non-fluorescent until oxidized by ROS. We found that ROS formation occurred immediately after irradiation, continued for several hours, and resulted in oxidative DNA damage. Therefore, the origin of hyper-radiosensitivity of T lymphocytes seemed to be the high production of ROS in the mitochondrial DNA following irradiation.     

Mouse model of N-acetylgalactosamine-6-sulfate sulfatase deficiency (Galns-/-) produced by targeted disruption of the gene defective in Morquio A disease

Mucopolysaccharidosis IVA is an autosomal recessive disorder caused by a deficiency of N-acetylgalactosamine-6-sulfate sulfatase (GALNS), a lysosomal enzyme required for the stepwise degradation of keratan sulfate (KS) and chondroitin-6-sulfate (C6S). To generate a model for studies of the pathophysiology and of potential therapies, we disrupted exon 2 of Galns, the homologous murine gene. Homozygous Galns-/- mice have no detectable GALNS enzyme activity and show increased urinary glycosaminoglycan (GAGs) levels. These mice accumulate GAGs in multiple tissues including liver, kidney, spleen, heart, brain and bone marrow. At 2 months old, lysosomal storage is present primarily within reticuloendothelial cells such as Kupffer cells and cells of the sinusoidal lining of the spleen. Additionally, by 12 months old, vacuolar change is observed in the visceral epithelial cells of glomeruli and cells at the base of heart valves but it is not present in parenchymal cells such as hepatocytes and renal tubular epithelial cells. In the brain, hippocampal and neocortical neurons and meningeal cells had lysosomal storage. KS and C6S were more abundant in the cytoplasm of corneal epithelial cells of Galns-/- mice compared with wild-type mice by immunohistochemistry. Radiographs revealed no change in the skeletal bones of mice up to 12 months old. Thus, targeted disruption of the murine Galns gene has produced a murine model, which shows visceral storage of GAGs but lacks the skeletal features. The complete absence of GALNS in mutant mice makes them useful for studies of pharmacokinetics and tissue targeting of recombinant GALNS designed for enzyme replacement.     

In vivo expansion of CD4+Foxp3+ regulatory T cells mediated by GITR molecules

CD4(+)Foxp3(+) regulatory T cells (Treg cells) play an important role in maintaining self-tolerance as suppressive/regulatory CD4 T cells. In vitro analyses have revealed the characteristics of Treg cells, that is, hyporesponsiveness when stimulated via TCR in the presence of splenic APC. In this study, we report a new mAb, G3c, which can induce the expansion of Treg cells stimulated with anti-CD3 Ab along with splenic APC, the culture conditions in which Treg cells exhibit hyporesponsiveness. Surprisingly, G3c mAb recognized glucocorticoid-induced TNFR family-related proteins (GITR). G3c mAb had stronger co-stimulatory activity for both Treg cells and responder T cells than another anti-GITR Ab (DTA1) in vitro. The in vivo administration of G3c increased the number of Treg cells and had less effect in inducing anti-tumor immunity in normal mice, although G3c had some anti-tumor effect on non-Treg cells in the absence of Treg cells in vivo, in contrast to the anti-tumor therapeutic effect of DTA1 in normal mice. Therefore, we need to know that the manipulation of immune responses with the use of anti-GITR Abs results from a balance between co-stimulatory effects on Treg cells and on responder cells, and we must aim at a narrow window leading to the therapeutic effects.