DEVELOPMENTS IN CERAMIC AND OTHER THERMAL SPRAY COATINGS FOR PAPER-MACHINE ROLLS

Mike Verlander 한국펄프·종이공학회 2000 펄프종이기술국제세미나 Vol.26 No.-

Expression of the rhesus glycoproteins, ammonia transporter family members, RHCG and RHBG in male reproductive organs

Lee, Hyun-Wook,Verlander, Jill W,Handlogten, Mary E,Han, Ki-Hwan,Cooke, Paul S,Weiner, I David BioScientifica Ltd 2013 Reproduction Vol.146 No.3

<P>The rhesus glycoproteins, Rh B glycoprotein (RHBG) and Rh C glycoprotein (RHCG), are recently identified ammonia transporters. Rhcg expression is necessary for normal male fertility, but its specific cellular expression is unknown, and Rhbg has not been reported to be expressed in the male reproductive tract. This study sought to determine the specific cellular expression of Rhcg, to determine whether Rhbg is expressed in the male reproductive tract, and, if so, to determine which cells express Rhbg using real-time RT-PCR, immunoblot analysis, and immunohistochemistry. Both Rhbg and Rhcg were expressed throughout the male reproductive tract. In the testis, high levels of Rhbg were expressed in Leydig cells, and Rhcg was expressed in spermatids during the later stages of their maturation (steps 13–16) in stages I–VIII of the seminiferous epithelium cycle. In the epididymis, basolateral Rhbg was present in narrow cells in the initial segment, in principal cells in the upper corpus, and in clear cells throughout the epididymis. Apical Rhcg immunolabel was present in principal cells in the caput and upper corpus epididymidis and in clear cells in the middle and lower corpus and cauda epididymidis. In the vas deferens, apical Rhcg immunolabel and basolateral Rhbg immunolabel were present in some principal cells and colocalized with H<SUP>+</SUP>-ATPase immunolabel. We conclude that both Rhbg and Rhcg are highly expressed in specific cells in the male reproductive tract where they can contribute to multiple components of male fertility.</P>

Renal ammonia excretion in response to hypokalemia: effect of collecting duct-specific Rh C glycoprotein deletion.

Lee, Hyun-Wook,Verlander, Jill W,Bishop, Jesse M,Handlogten, Mary E,Han, Ki-Hwan,Weiner, I David American Physiological Society 2013 American Journal of Physiology Vol.304 No.4

<P>The Rhesus factor protein, Rh C glycoprotein (Rhcg), is an ammonia transporter whose expression in the collecting duct is necessary for normal ammonia excretion both in basal conditions and in response to metabolic acidosis. Hypokalemia is a common clinical condition associated with increased renal ammonia excretion. In contrast to basal conditions and metabolic acidosis, increased ammonia excretion during hypokalemia can lead to an acid-base disorder, metabolic alkalosis, rather than maintenance of acid-base homeostasis. The purpose of the current studies was to determine Rhcg's role in hypokalemia-stimulated renal ammonia excretion through the use of mice with collecting duct-specific Rhcg deletion (CD-Rhcg-KO). In mice with intact Rhcg expression, a K(+)-free diet increased urinary ammonia excretion and urine alkalinization and concurrently increased Rhcg expression in the collecting duct in the outer medulla. Immunohistochemistry and immunogold electron microscopy showed hypokalemia increased both apical and basolateral Rhcg expression. In CD-Rhcg-KO, a K(+)-free diet increased urinary ammonia excretion and caused urine alkalinization, and the magnitude of these changes did not differ from mice with intact Rhcg expression. In mice on a K(+)-free diet, CD-Rhcg-KO increased phosphate-dependent glutaminase (PDG) expression in the outer medulla. We conclude that hypokalemia increases collecting duct Rhcg expression, that this likely contributes to the hypokalemia-stimulated increase in urinary ammonia excretion, and that adaptive increases in PDG expression can compensate for the absence of collecting duct Rhcg.</P>

[지상 4] Ultrastructural localization of RhBG and RhCG in collecting duct of rat kidney

Ki-Hwan Han,Jill W. Verlander,David Weiner,Jin Kim 대한체질인류학회 2005 대한체질인류학회 학술대회 연제 초록 Vol.48 No.-

Effect of reduced renal mass on renal ammonia transporter family, Rh C glycoprotein and Rh B glycoprotein, expression.

Kim, Hye-Young,Baylis, Chris,Verlander, Jill W,Han, Ki-Hwan,Reungjui, Sirirat,Handlogten, Mary E,Weiner, I David American Physiological Society 2007 American Journal of Physiology Vol.293 No.4

<P>Kidneys can maintain acid-base homeostasis, despite reduced renal mass, through adaptive changes in net acid excretion, of which ammonia excretion is the predominant component. The present study examines whether these adaptations are associated with changes in the ammonia transporter family members, Rh B glycoprotein (Rhbg) and Rh C glycoprotein (Rhcg). We used normal Sprague-Dawley rats and a 5/6 ablation-infarction model of reduced renal mass; control rats underwent sham operation. After 1 wk, glomerular filtration rate, assessed as creatinine clearance, was decreased, serum bicarbonate was slightly increased, and Na(+) and K(+) were unchanged. Total urinary ammonia excretion was unchanged, but urinary ammonia adjusted for creatinine clearance, an index of per nephron ammonia metabolism, increased significantly. Although reduced renal mass did not alter total Rhcg protein expression, both light microscopy and immunohistochemistry with quantitative morphometric analysis demonstrated hypertrophy of both intercalated cells and principal cells in the cortical and outer medullary collecting duct that was associated with increased apical and basolateral Rhcg polarization. Rhbg expression, analyzed using immunoblot analysis, immunohistochemistry, and measurement of cell-specific expression, was unchanged. We conclude that altered subcellular localization of Rhcg contributes to adaptive changes in single-nephron ammonia metabolism and maintenance of acid-base homeostasis in response to reduced renal mass.</P>

Intercalated cell-specific Rh B glycoprotein deletion diminishes renal ammonia excretion response to hypokalemia.

Bishop, Jesse M,Lee, Hyun-Wook,Handlogten, Mary E,Han, Ki-Hwan,Verlander, Jill W,Weiner, I David American Physiological Society 2013 American journal of physiology. Renal physiology Vol.304 No.4

<P>The ammonia transporter family member, Rh B Glycoprotein (Rhbg), is an ammonia-specific transporter heavily expressed in the kidney and is necessary for the normal increase in ammonia excretion in response to metabolic acidosis. Hypokalemia is a common clinical condition in which there is increased renal ammonia excretion despite the absence of metabolic acidosis. The purpose of this study was to examine Rhbg's role in this response through the use of mice with intercalated cell-specific Rhbg deletion (IC-Rhbg-KO). Hypokalemia induced by feeding a K(+)-free diet increased urinary ammonia excretion significantly. In mice with intact Rhbg expression, hypokalemia increased Rhbg protein expression in intercalated cells in the cortical collecting duct (CCD) and in the outer medullary collecting duct (OMCD). Deletion of Rhbg from intercalated cells inhibited hypokalemia-induced changes in urinary total ammonia excretion significantly and completely prevented hypokalemia-induced increases in urinary ammonia concentration, but did not alter urinary pH. We conclude that hypokalemia increases Rhbg expression in intercalated cells in the cortex and outer medulla and that intercalated cell Rhbg expression is necessary for the normal increase in renal ammonia excretion in response to hypokalemia.</P>

흰쥐의 집합관 사이세포에서 암모니아 운반체 RhBG의 세포내 미세구조적 위치

한기환(Ki-Hwan Han),김완영(Wan-Young Kim),Jill W. Verlander, I. David Weiner, 김 진(Jin Kim) 대한해부학회 2005 Anatomy & Cell Biology Vol.38 No.2

콩팥의 집합관에서 일어나는 암모니아 배설은 산-염기평형의 조절에 중요한 역할을 한다. RhBG (Rh B Glycoprotein)는 최근에 밝혀진 새로운 암모니아 운반체(ammonium transporter)로 콩팥의 집합관에 존재하는 것으로 알려져 있다. 이 연구의 목적은 집합관 사이세포(intercalated cell)에서 RhBG의 미세구조적 위치를 관찰하는 것이다. Sprague-Dawley계의 흰쥐를 대상으로 광학 및 전자현미경적 면역세포화학법을 시행하였다. RhBG 면역반응성은 콩팥의 겉질, 바깥수질 및 속수질 시작부분 집합관의 일부 세포에서 관찰되었다. RhBG 면역반응성은 세포막자유면에 H±-ATPase를 발현하는 사이세포에서 강하게 나타났으나, pendrin을 발현하는 B형 세포와 주세포에서는 아주 약하거나 관찰되지 않았다. 전자현미경으로 관찰한 결과 RhBG는 주로 미세주름(microplicae)이 발달한 A형 사이세포의 바닥가쪽면 세포막(basolateral plasma membrane) 및 세포막주름 (infolding)에 위치하였으며, 미세융모(microvilli)를 가지고 있는 B형 사이세포에서는 아주 약하게 나타나는 것을 확인하였다. 이상의 결과로 암모니아 운반체 RhBG는 집합관에서 주로 산을 분비하는 A형 사이세포의 바닥가쪽면 세포막에 위치하여 산-염기평형과 관련된 암모니아 배설을 조절할 것으로 생각된다. Ammonia excretion in the renal collecting duct is critical in the regulation of the acid-base homeostasis. A novel family of ammonium transporter protein, Rh B Glycoprotein (RhBG) was recently identified in the mouse and rat kidney collecting duct. The purpose of this was to examine the ultrastructural localization of RhBG in the collecting duct. Rat kidneys were processed for light and electron microscope immunocytochemistry using anti- RhBG rabbit polyclonal antibody. Strong RhBG immunolabeling was observed in the basolateral plasma membrane of type A intercalated cells in the collecting duct. In contrast, RhBG labeling was very weak or negative in type B intercalated cells and rincipal cells. Transmission electron microscopy confirmed that RhBG immunostaining was located mainly in the basolateral plasma membrane and infoldings of type A intercalated cells, but very weak in type B cells. RhBG labeling was not observed in the apical plasma membrane both in type A and B cells. These results demonstrate that RhBG is a basolateral transporter in acid-secreting type A cells and may mediate ammonia excretion in the collecting duct.

Expression of the ammonia transporter family member, Rh B Glycoprotein, in the human kidney

Han, Ki-Hwan,Lee, Hyun-Wook,Handlogten, Mary E.,Whitehill, Florence,Osis, Gunars,Croker, Byron P.,Clapp, William L.,Verlander, Jill W.,Weiner, I. David American Physiological Society 2013 American journal of physiology. Renal physiology Vol.304 No.7

<P>The ammonia transporter family member, Rh B Glycoprotein (RhBG/Rhbg), is essential for ammonia transport by the rodent kidney, but in the human kidney mRNA but not protein expression has been reported. Because ammonia transport is fundamental for acid-base homeostasis, the current study addressed RhBG expression in the human kidney. Two distinct RhBG mRNA sequences have been reported, with different numbers of consecutive cytosines at nt1265 and thus encoding different carboxy-tails. Sequencing the region of difference in both human kidney and liver mRNA showed eight sequential cytosines, not seven as in some reports. Knowing the correct mRNA sequence for RhBG, we then assessed RhBG protein expression using antibodies against the correct amino acid sequence. Immunoblot analysis demonstrated RhBG protein expression in human kidney and immunohistochemistry identified basolateral RhBG in connecting segment (CNT) and the cortical and outer medullary collecting ducts. Colocalization of RhBG with multiple cell-specific markers demonstrated that that CNT cells and collecting duct type A intercalated cells express high levels of RhBG, and type B intercalated cells and principal cells do not express detectable RhBG. Thus, these studies identify the correct mRNA and thus protein sequence for human RhBG and show that the human kidney expresses basolateral RhBG protein in CNT, type A intercalated cells, and non-A, non-B cells. We conclude that RhBG can mediate an important role in human renal ammonia transport.</P>

Transcriptomes of major renal collecting duct cell types in mouse identified by single-cell RNA-seq

Chen, Lihe,Lee, Jae Wook,Chou, Chung-Lin,Nair, Anil V.,Battistone, Maria A.,Pă,unescu, Teodor G.,Merkulova, Maria,Breton, Sylvie,Verlander, Jill W.,Wall, Susan M.,Brown, Dennis,Burg, Maurice B. National Academy of Sciences 2017 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.114 No.46

<P><B>Significance</B></P><P>A long-term goal in mammalian biology is to identify the genes expressed in every cell type of the body. In the kidney, the expressed genes (i.e., transcriptome) of all epithelial cell types have already been identified with the exception of the cells that make up the renal collecting duct, which is responsible for regulation of blood pressure and body fluid composition. Here, single-cell RNA-sequencing was used in mouse to identify transcriptomes for the major collecting duct cell types: type A intercalated cells, type B intercalated cells, and principal cells. The information was used to create a publicly accessible online resource. The data allowed identification of genes that are selectively expressed in each cell type, which is informative for cell-level understanding of physiology and pathophysiology.</P><P>Prior RNA sequencing (RNA-seq) studies have identified complete transcriptomes for most renal epithelial cell types. The exceptions are the cell types that make up the renal collecting duct, namely intercalated cells (ICs) and principal cells (PCs), which account for only a small fraction of the kidney mass, but play critical physiological roles in the regulation of blood pressure, extracellular fluid volume, and extracellular fluid composition. To enrich these cell types, we used FACS that employed well-established lectin cell surface markers for PCs and type B ICs, as well as a newly identified cell surface marker for type A ICs, c-Kit. Single-cell RNA-seq using the IC- and PC-enriched populations as input enabled identification of complete transcriptomes of A-ICs, B-ICs, and PCs. The data were used to create a freely accessible online gene-expression database for collecting duct cells. This database allowed identification of genes that are selectively expressed in each cell type, including cell-surface receptors, transcription factors, transporters, and secreted proteins. The analysis also identified a small fraction of hybrid cells expressing aquaporin-2 and anion exchanger 1 or pendrin transcripts. In many cases, mRNAs for receptors and their ligands were identified in different cells (e.g., <I>Notch2</I> chiefly in PCs vs. <I>Jag1</I> chiefly in ICs), suggesting signaling cross-talk among the three cell types. The identified patterns of gene expression among the three types of collecting duct cells provide a foundation for understanding physiological regulation and pathophysiology in the renal collecting duct.</P>