Kenny-Caffey syndrome (KCS) and the similar but more severe osteocraniostenosis (OCS) are genetic conditions characterized by impaired skeletal development with small and dense bones, short stature, and primary hypoparathyroidism with hypocalcemia. We studied five individuals with KCS and five with OCS and found that all of them had heterozygous mutations in FAM111A. One mutation was identified in four unrelated individuals with KCS, and another one was identified in two unrelated individuals with OCS; all occurred de novo. Thus, OCS and KCS are allelic disorders of different severity. FAM111A codes for a 611 amino acid protein with homology to trypsin-like peptidases. Although FAM111A has been found to bind to the large T-antigen of SV40 and restrict viral replication, its native function is unknown. Molecular modeling of FAM111A shows that residues affected by KCS and OCS mutations do not map close to the active site but are clustered on a segment of the protein and are at, or close to, its outer surface, suggesting that the pathogenesis involves the interaction with as yet unidentified partner proteins rather than impaired catalysis. FAM111A appears to be crucial to a pathway that governs parathyroid hormone production, calcium homeostasis, and skeletal development and growth.

Adipsic (or essential) hypernatremia is a rare hypernatremia caused by a deficiency in thirst regulation and vasopressin release. In 2010, we reported a case in which autoantibodies targeting the sensory circumventricular organs (sCVOs) caused adipsic hypernatremia without hypothalamic structural lesions demonstrable by magnetic resonance imaging (MRI); sCVOs include the subfornical organ (SFO) and organum vasculosum of the lamina terminalis (OVLT), which are centers for the monitoring of body-fluid conditions and the control of water and salt intakes, and harbor neurons innervating hypothalamic nuclei for vasopressin release. We herein report three newly identified patients (3- to 8-year-old girls on the first visit) with similar symptoms. The common features of the patients were extensive hypernatremia without any sensation of thirst and defects in vasopressin response to serum hypertonicity. Despite these features, we could not detect any hypothalamic structural lesions by MRI. Immunohistochemical analyses using the sera of the three patients revealed that antibodies specifically reactive to the mouse SFO were present in the sera of all cases; in one case, the antibodies also reacted with the mouse OVLT. The immunoglobulin (Ig) fraction of serum obtained from one patient was intravenously injected into wild-type mice to determine whether the mice developed similar symptoms. Mice injected with a patient's Ig showed abnormalities in water/salt intake, vasopressin release, and diuresis, which resultantly developed hypernatremia. Prominent cell death and infiltration of reactive microglia was observed in the SFO of these mice. Thus, autoimmune destruction of the SFO may be the cause of the adipsic hypernatremia. This study provides a possible explanation for the pathogenesis of adipsic hypernatremia without demonstrable hypothalamus-pituitary lesions.

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EDTA-dependent pseudothrombocytopenia (PTCP) is characterised by a low platelet count caused by autoantibodies in the serum reacting with EDTA-anticoagulated blood. EDTA-dependent PTCP is caused by a factor that retains EDTA anticoagulation activity in the serum. We report here that a neonate from a mother with PTCP presented with transient low platelet counts when EDTA was used as an anticoagulant. To confirm the transmission of a maternal serum factor to the neonate, we examined to add the maternal serum into the normal blood. Platelet count decreased significantly after adding maternal serum. Clumped platelets were also observed in the smears of mixed samples.

Introduction: Chronic granulomatous disease (CGD) is an inherited immunodeficiency due to a mutation in genes that encode the subunits of NADPH oxidase of phagocytes. Phagocytes of CGD can not generate the reactive oxidative species (ROS), whereas nitric oxide (NO) production of CGD phagocytes is increased in response to calcium ionophore, A23187, compared with that of phagocytes from healthy subjects. Recently, X-linked CGD (X-CGD) patients showed lower oxidative stress and higher flow-mediated dilation, suggesting that endothelial cell function is affected by NO production of phagocytes. We studied the effects of NO on the regulation of endothelial gene expression related to dilator and constrictive effect of blood vessels, such as NOS3 and EDN1 using neutrophils from X-CGD patients. Methods: Eighteen X-CGD patients and 18 age-matched healthy male subjects were enrolled in this study from 2009 to 2013. NO production of phagocytes was assessed by flow cytometry using DAF2/DA fluorescent probe. Human umbilical vein endothelial cells (HUVECs) were co-cultured with human neutrophils of X-CGD or healthy subjects in response to calcium ionophore,A23187 without cell to cell contact using the Transwell-permeable support systems. The expression of endothelial NOS3 and EDN1 mRNA gene in HUVECs were quantified by real-time PCR. Results: Neutrophils of X-CGD patients showed significantly higher production of NO in response to A23187 for 30 to 60 minutes than those of normal subjects detected by flow cytometric analyses. NO concentration artificially generated by NO donor was significantly decreased by ROS produced by xanthine and xanthine oxidase. Similarly, neutrophils from healthy subjects, but not from X-CGD stimulated with A23187 induced the decrease in the concentration of NO. These results strongly suggest that the lack of ROS generation in CGD neutrophils leads to the increase of NO production in response to A23187. HUVECs were incubated with NO generation system, ROS generation system alone or with both systems. The expression of NOS3 and EDN1 was significantly decreased depending on the concentration of extracellular NO. In contrast, both NOS3 and EDN1 expression was significantly up-regulated under the ROS generation system without NO. Next, HUVECs were incubated by X-CGD neutrophils or by control neutrophils with or without A23187 for 30 minutes using the wells divided by membrane (0.45μm) to prevent cell to cell contact. Both NOS3 and EDN1 expression of HUVECs incubated with X-CGD neutrophils was significantly down-regulated under A23187 stimulation compared with normal neutrophils (112±117 vs. 34.5±39.9, n=8, p<0.05, 0.94± 0.24 vs. 0.61±0.24, n=5, p<0.05, respectively). Conclusion: This study demonstrated that the stimulated X-CGD neutrophils induced the decreased endothelial NOS3 and EDN1 gene expression through the excessive generation of NO due to the lack of ROS production. These findings suggest that ROS generated by phagocytes may modulate arterial tone affecting the amount of NO, a potent vasodilator molecule produced by endothelial cells. Disclosures No relevant conflicts of interest to declare.