scholarly journals CD177 modulates the function and homeostasis of tumor-infiltrating regulatory T cells

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Myung-Chul Kim ◽  
Nicholas Borcherding ◽  
Kawther K. Ahmed ◽  
Andrew P. Voigt ◽  
Ajaykumar Vishwakarma ◽  
...  

AbstractRegulatory T (Treg) cells are one of the major immunosuppressive cell types in cancer and a potential target for immunotherapy, but targeting tumor-infiltrating (TI) Treg cells has been challenging. Here, using single-cell RNA sequencing of immune cells from renal clear cell carcinoma (ccRCC) patients, we identify two distinct transcriptional fates for TI Treg cells, Fate-1 and Fate-2. The Fate-1 signature is associated with a poorer prognosis in ccRCC and several other solid cancers. CD177, a cell surface protein normally expressed on neutrophil, is specifically expressed on Fate-1 TI Treg cells in several solid cancer types, but not on other TI or peripheral Treg cells. Mechanistically, blocking CD177 reduces the suppressive activity of Treg cells in vitro, while Treg-specific deletion of Cd177 leads to decreased tumor growth and reduced TI Treg frequency in mice. Our results thus uncover a functional CD177+ TI Treg population that may serve as a target for TI Treg-specific immunotherapy.

Pharmaceutics ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 888
Author(s):  
Hiro Uemachi ◽  
Yuuya Kasahara ◽  
Keisuke Tanaka ◽  
Takumi Okuda ◽  
Yoshihiro Yoneda ◽  
...  

Nucleic acid aptamers have attracted considerable attention as next-generation pharmaceutical agents and delivery vehicles for small molecule drugs and therapeutic oligonucleotides. Chemical modification is an effective approach for improving the functionality of aptamers. However, the process of selecting appropriately modified aptamers is laborious because of many possible modification patterns. Here, we describe a hybrid-type systematic evolution of ligands by exponential enrichment (SELEX) approach for the generation of the artificial nucleic acid aptamers effective against human TROP2, a cell surface protein identified by drug discovery as a promising target for cancer therapy. Capillary electrophoresis SELEX was used for the pre-screening of multiple modified nucleic acid libraries and enrichment of TROP2 binding aptamers in the first step, followed by functional screening using cell-SELEX in the second step for the generation of cell-internalizing aptamers. One representative aptamer, Tac-B1, had a nanomolar-level affinity to human TROP2 and exhibited elevated capacity for internalization by cells. Because of the growing interest in the application of aptamers for drug delivery, our hybrid selection approach has great potential for the generation of functional artificial nucleic acid aptamers with ideal modification patterns in vitro.


Development ◽  
1997 ◽  
Vol 124 (8) ◽  
pp. 1433-1441 ◽  
Author(s):  
A. Nose ◽  
T. Umeda ◽  
M. Takeichi

Drosophila Connectin (CON) is a cell surface protein of the leucine-rich repeat family. During the formation of neuromuscular connectivity, CON is expressed on the surface of a subset of embryonic muscles and on the growth cones and axons of the motoneurons that innervate these muscles, including primarily SNa motoneurons and their synaptic targets (lateral muscles). In vitro, CON can mediate homophilic cell adhesion. In this study, we generated transgenic lines that ectopically expressed CON on all muscles. In the transformant embryos and larvae, SNa motoneurons often inappropriately innervated a neighboring non-target muscle (muscle 12) that ectopically expressed CON. Furthermore, the ectopic synapse formation was dependent on the endogenous CON expression on the SNa motoneurons. These results show that CON can function as an attractive and homophilic target recognition molecule in vivo.


2005 ◽  
Vol 94 (11) ◽  
pp. 1004-1011 ◽  
Author(s):  
Frédéric Adam ◽  
Shilun Zheng ◽  
Nilesh Joshi ◽  
David Kelton ◽  
Amin Sandhu ◽  
...  

SummaryMultimerin 1 (MMRN1) is a large, soluble, polymeric, factor V binding protein and member of the EMILIN protein family.In vivo, MMRN1 is found in platelets, megakaryocytes, endothelium and extracellular matrix fibers, but not in plasma. To address the mechanism of MMRN1 binding to activated platelets and endothelial cells, we investigated the identity of the major MMRN1 receptors on these cells using wild-type and RGE-forms of recombinant MMRN1. Ligand capture, cell adhesion, ELISA and flow cytometry analyses of platelet-MMRN1 binding, indicated that MMRN1 binds to integrins αIIbβ3 and αvβ3. Endothelial cell binding to MMRN1 was predominantly mediated by αvβ3 and did not require the MMRN1 RGD site or cellular activation. Like many other αvβ3 ligands, MMRN1 had the ability to support adhesion of additional cell types, including stimulated neutrophils. Expression studies, using a cell line capable of endothelial-like MMRN1 processing, indicated that MMRN1 adhesion to cellular receptors enhanced its extracellular matrix fiber assembly. These studies implicate integrin-mediated binding in MMRN1 attachment to cells and indicate that MMRN1 is a ligand for αIIbβ3 and αvβ3.


Microbiology ◽  
2010 ◽  
Vol 156 (9) ◽  
pp. 2818-2828 ◽  
Author(s):  
Maria Laura Ferrando ◽  
Susana Fuentes ◽  
Astrid de Greeff ◽  
Hilde Smith ◽  
Jerry M. Wells

We have identified apuA in Streptococcus suis, which encodes a bifunctional amylopullulanase with conserved α-amylase and pullulanase substrate-binding domains and catalytic motifs. ApuA exhibited properties typical of a Gram-positive surface protein, with a putative signal sequence and LPKTGE cell-wall-anchoring motif. A recombinant protein containing the predicted N-terminal α-amylase domain of ApuA was shown to have α-(1,4) glycosidic activity. Additionally, an apuA mutant of S. suis lacked the pullulanase α-(1,6) glycosidic activity detected in a cell-surface protein extract of wild-type S. suis. ApuA was required for normal growth in complex medium containing pullulan as the major carbon source, suggesting that this enzyme plays a role in nutrient acquisition in vivo via the degradation of glycogen and food-derived starch in the nasopharyngeal and oral cavities. ApuA was shown to promote adhesion to porcine epithelium and mucus in vitro, highlighting a link between carbohydrate utilization and the ability of S. suis to colonize and infect the host.


F1000Research ◽  
2018 ◽  
Vol 7 ◽  
pp. 211 ◽  
Author(s):  
Lukas Vrba ◽  
Bernard W. Futscher

We have previously described a hominid-specific long non-coding RNA, MORT (also known as ZNF667-AS1, Gene ID: 100128252), which is expressed in all normal cell types, but epigenetically silenced during cancer-associated immortalization of human mammary epithelial cells.  Initial analysis of The Cancer Genome Atlas (TCGA) showed that 15 of 17 cancer types, which represent the 10 most common cancers in women and men, display DNA methylation associated MORT silencing in a large fraction of their tumors.  In this study we analyzed MORT expression and DNA methylation state in the remaining 16 TCGA cancer types not previously reported.  Seven of the 16 cancer types showed DNA methylation linked MORT silencing in a large fraction of their tumors.  These are carcinomas (cervical cancer, and cancers of esophagus, stomach, and bile duct), and the non-epithelial tumors mesothelioma, sarcoma, and uterine carcinosarcoma.  Together with the findings from our previous report, MORT expression is silenced by aberrant DNA methylation in 22 of 33 of TCGA cancer types.  These 22 cancers include most carcinoma types, blood derived cancers and sarcomas.  In conclusion, results suggest that the MORT gene is one of the most common epigenetic aberrations seen in human cancer.  Coupled with the timing of MORT gene silencing during in vitro epithelial cell immortalization and its occurrence early in the temporal arc of human carcinogenesis, this provides strong circumstantial evidence for a tumor suppressor role for MORT.


Parasitology ◽  
1997 ◽  
Vol 115 (6) ◽  
pp. 581-590 ◽  
Author(s):  
A. HEMPHILL ◽  
R. FELLEISEN ◽  
B. CONNOLLY ◽  
B. GOTTSTEIN ◽  
B. HENTRICH ◽  
...  

Neospora caninum is an apicomplexan parasite of veterinary importance which invades many different cell types and tissues. N. caninum tachyzoites proliferate intracellularly by endodyogeny. Eventually the massive proliferation of tachyzoites leads to host cell lysis and the newly formed parasites are released and invade neighbouring cells. Tachyzoite cell surface molecules could serve as ligands, mediating host cell adhesion and invasion. Nc-p43 is a recently identified N. caninum tachyzoite surface protein which is functionally involved in the processes leading to host cell invasion in vitro. Affinity-purified antibodies directed against Nc-p43 were used to screen a lambda gt22A-cDNA expression library constructed from N. caninum tachyzoites. The cDNA insert of one immunoreactive clone was subcloned and expressed in E. coli as a poly-histidine fusion protein. The identity of the resulting recombinant antigen termed recNc-p43 was confirmed by immunoblotting, immunofluorescence and electron microscopy using affinity-purified antibodies. The sequence of the cDNA insert encoding recNc-p43 was determined. Analysis of the deduced amino acid sequence revealed that Nc-p43 exhibited similarity to SAG1 (p30) and SAG3 (p43), 2 major surface antigens of Toxoplasma gondii tachyzoites. These similarities were not reflected on the immunochemical level, since no cross-antigenicity between SAG1, SAG3 and Nc-p43 was observed.


Microbiology ◽  
2002 ◽  
Vol 148 (2) ◽  
pp. 433-442 ◽  
Author(s):  
Stefan Roos ◽  
Hans Jonsson

A gene from Lactobacillus reuteri 1063 encoding a cell-surface protein, designated Mub, that adheres to mucus components in vitro has been cloned and sequenced. The deduced amino acid sequence of Mub (358 kDa) shows the presence of 14 approximately 200 aa repeats and features typical for other cell-surface proteins of Gram-positive bacteria. Fusion proteins consisting of different repeats of Mub and the maltose-binding protein (MBP) were produced. These proteins adhered to pig mucus components, with molecular masses ranging from <0·1 to >2 MDa, to pig gastric mucin and to hen intestinal mucus. The binding of Mub to mucus components occurred in the pH range 3–7·4, with maximum binding at pH 4–5 and could be partly inhibited by the glycoprotein fetuin. Affinity-purified antibodies against recombinant Mub were used in immunofluorescence microscopy to demonstrate the presence of Mub on the cell surface of strain 1063. By using the antibodies in a Western blot analysis, Mub could also be detected in the growth medium. The results implicate Mub as a cell-surface protein that is involved in Lactobacillus interactions with mucin and in colonization of the digestive tract.


1977 ◽  
Vol 145 (1) ◽  
pp. 136-150 ◽  
Author(s):  
A E Butterworth ◽  
J R David ◽  
D Franks ◽  
A A Mahmoud ◽  
P H David ◽  
...  

After earlier observations that antibody-dependent, cell-mediated damage to 51Cr-labeled schistosomula can be ablated by pretreatment of a mixed preparation of human peripheral blood leukocytes with an anti-eosinophil serum and complement, we investigated the cytotoxic effects of eosinophil-enriched cell preparations. Preparations containing up to 98.5% eosinophils and devoid of neutrophils were effective in mediating antibody-dependent damage to schistosomula. Preparations enriched in mononuclear cells or in neutrophils, and devoid of eosinophils, were inactive. Eosinophils from some patients with eosinophilia induced by schistosomiasis were less active on a cell-to-cell basis than cells from normal individuals. The possibility that such cells were initially blocked by immune complexes was considered, and it was found that reasonable cytotoxicity by purified eosinophils from patients with eosinophilia could be generated by overnight cultures. A possible requirement for cooperation between eosinophils and other cell types was also studied. Lymphocytes, neutrophils and monocytes failed to enhance eosinophil-mediated cytotoxicity. These results provide further evidence that the eosinophil is the only cell in man responsible for antibody-dependent, complement-independent damage to schistosomula in vitro. Eosinophils from individuals, however, differ in their cytotoxic potential by a mechanism yet to be elucidated. The possible relationship of these findings to immunity in vivo is discussed.


Reproduction ◽  
2004 ◽  
Vol 127 (2) ◽  
pp. 151-157 ◽  
Author(s):  
Yong-Hai Li ◽  
Yi Hou ◽  
Wei Ma ◽  
Jin-Xiang Yuan ◽  
Dong Zhang ◽  
...  

CD9 is a cell surface protein that participates in many cellular processes, such as cell adhesion. Fertilization involves sperm and oocyte interactions including sperm binding to oocytes and sperm–oocyte fusion. Thus CD9 may play an essential role during fertilization in mammals. The present study was conducted to examine whether CD9 is present in porcine gametes and whether it participates in the regulation of sperm–oocyte interactions. The presence of CD9 in ovarian tissues, oocytes and spermatozoa was examined by immunohistochemistry, immunofluorescence and immunoblotting. Sperm binding and penetration of oocytes treated with CD9 antibody were examined by in vitro fertilization. The results showed that CD9 was present on the plasma membrane of oocytes at different developmental stages. A 24 kDa protein was found in oocytes during in vitro maturation by immunoblotting and its quantity was significantly (P < 0.001) increased as oocytes underwent maturation and reached the highest level after the oocytes had been cultured for 44 h. No positive CD9 staining was found in the spermatozoa. Both sperm binding to ooplasma and sperm penetration into oocytes were significantly (P < 0.01) reduced in anti-CD9 antibody-treated oocytes (1.2 ± 0.2 per oocyte and 16.6% respectively) as compared with oocytes in the controls (2.5 ± 0.4 per oocyte and 70.3% respectively). These results indicated that CD9 is expressed in pig oocytes during early growth and meiotic maturation and that it participates in sperm–oocyte interactions during fertilization.


2001 ◽  
Vol 360 (3) ◽  
pp. 579-587 ◽  
Author(s):  
Dieter KÜBLER

A variety of cell membrane proteins become phosphorylated in their ecto-domains by cell-surface protein kinase (ecto-PK) activities, as detected in a broad spectrum of cell types. This study reports the isolation and identification of a frequent ecto-PK substrate, ecto-p120, using HeLa cells as a model. Data from MS and further biochemical and immunochemical means identified ecto-p120 as a cell-surface homologue of human nucleolar phosphoprotein p140 (hNopp140), which belongs to the family of argyrophilic (AgNOR-stainable) proteins. The superposition of 32P-labelled ecto-nucleolar phosphoprotein p140 (ecto-Nopp140) with anti-Nopp140 immunostaining could be demonstrated in a wide range of cell lines without any exceptions, suggesting a nearly universal occurrence of cell-surface Nopp140. A previous, tentative association of ecto-p120 with the nucleoplasmic pre-mRNA-binding protein hnRNP U has thus been supplanted, since improved purification techniques have allowed unambiguous identification of this ecto-PK cell-surface substrate. Furthermore, we have shown that rapid suppression of ecto-hNopp140 phosphorylation resulted upon a rise in the free extracellular calcium, while lowering the calcium concentrations returned ecto-Nopp140 phosphorylation to the original level. It is important to note that these Ca2+-dependent effects on ecto-Nopp140 phosphorylation are not accompanied by alterations in the phosphorylation of other ecto-PK substrates. Our results indicate that, in addition to nucleolin, a further nucleolar protein, which was considered initially to be strictly intracellular, is identified as a cell-surface phosphoprotein.


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