Journal: International journal of molecular sciences

Article Title: Regulation of Mertk Surface Expression via ADAM17 and γ-Secretase Proteolytic Processing.

doi: 10.3390/ijms25084404

Figure Lengend Snippet: Figure 1. Differentiation of THP-1 cells induced by PMA. (A) THP-1 monocytes are differentiated to macrophages and induced to express Mertk by the addition of 100 ng/mL of PMA for at least 24 h, while Axl expression is not induced. Likewise, Tyro3 expression remains stable and is unaffected by treatment. H1299 and Beas2B cells are used as positive controls for Mertk/Axl and Tyro3, respec- tively. The observed doublet for Mertk corresponds to fully glycosylated and partially glycosylated glycoforms. (B) THP-1 cells treated with 100 ng/mL of PMA over 48 h exhibit a decreased expression of Gas6 but an increased expression of Protein S. (C) MertK and Gas6 expression patterns over a time of 48 h after 100 ng/mL of PMA treatment as quantified from Western blots. (D) Bar plots showing MerTK and Gas6 expression quantified from Western blots at 0 h and post 72 h of 100 ng/mL of PMA treatment (significant differences were observed between the 0 h and 72 h time points for Gas6 (* p = 0.029) and MerTK (** p = 0.003), as determined by independent t-tests). (E) THP-1 cells were treated with 100 ng/mL of PMA over 72 h. mRNA was analyzed via qRT-PCR for Mertk, Axl, Protein S (ProS), Tyro3, and Gas6. Mertk transcription was highly elevated, more than 10-fold, due to PMA treatment, while Gas6 transcription was repressed more than 10-fold. (F) PMA treatment of THP-1s illustrates a complimentary phenomenon. As a monocyte, Gas6 is expressed with little Mertk expression; however, when differentiated, Mertk is highly expressed in favor of Gas6.

Article Snippet: Concentrated Gas6 reagents were analyzed for concentration via Western blotting using a Gas6 standard (R&D Systems, 885-GSB-050).

Techniques: Expressing, Western Blot, Quantitative RT-PCR

Journal: International journal of molecular sciences

Article Title: Regulation of Mertk Surface Expression via ADAM17 and γ-Secretase Proteolytic Processing.

doi: 10.3390/ijms25084404

Figure Lengend Snippet: Figure 3. γ-carboxylated Gas6 Reduces Full-length Mertk Expression and Decreases sMertk. (A) γ- carboxylation status (Gla) of Gas6 is regulated with the addition of Vitamin K or warfarin, producing either a γ-carboxylated, active ligand or a non-γ-carboxylated, inactive ligand, respectively. The carboxylation status (Gla) domain of Gas6 can bind with externalized PS. (B) Recombinant inactive (Gas6-W) and active (Gas6-VK) were produced via HEK293 transfection, with a mock transfection control (Mock). The amount of Gas6 was observed (bottom), while the carboxylation status that is responsible for ligand activity was determined for each (left, top). (C) PMA-differentiated THP-1s were treated for 4 h with either serum-free RPMI only (-), a mock transfection control, 10 nM of active Gas6 (Gas6-VK), or 10 nM of inactive Gas6 (Gas6-W). Treatments were alone or combined with inhibitors of 3 µM of GW280264X (an ADAM17 inhibitor), 5 µM of DAPT (a γ-secretase inhibitor), or 10 µM of MG132 (a proteasomal inhibitor). (D) Quantitative results indicate that Gas6, either active or inactive, does not stabilize the C-terminal fragments as shown in the DAPT and MG132 treatments (bands at 75 kDa). As denoted by sMertk (top), the cleavage is decreased with GW280264X treatment compared to the untreated control.

Article Snippet: Concentrated Gas6 reagents were analyzed for concentration via Western blotting using a Gas6 standard (R&D Systems, 885-GSB-050).

Techniques: Expressing, Recombinant, Produced, Transfection, Control, Activity Assay

Journal: International journal of molecular sciences

Article Title: Regulation of Mertk Surface Expression via ADAM17 and γ-Secretase Proteolytic Processing.

doi: 10.3390/ijms25084404

Figure Lengend Snippet: Figure 5. γ-carboxylated Gas6 reduces the tagged Mertk construct on cell membranes of THP-1 cells. (A) THP-1s expressing the tagged construct were starved for 18 h in serum-free RPMI and treated for 3 h. Flow cytometry data shows positive GFPs without staining. As expected, CHX treatment after 3 h reduces the expression of the construct. Gas6-VK, used at a concentration > 10 nM, decreases the FLAG-PE signal more when compared to other treatments known to induce cleavage (PMA, LPS). GW280264X is used as a control for Mertk cleavage. (B) Histogram analysis of “A.” Gas6-VK induces a shift in the FLAG-PE signal, showing that less surface Mertk is present. γ-Carboxylated Gas6 induced the degradation of Mertk on the cell membrane. (C) THP-1s treated with γ-Carboxylated Gas6 at a 10 nM concentration show increased MerTK phosphorylation, detected by immunoblotting against pMerTK. (D) THP-1s expressing the tagged construct, treated with >10 nM of Gas6-VK + 1 µM of PS, show a reduced level of both domains of the tagged construct, suggesting that the Gas6-VK + PS treatment is leading to a degradation of the full-length receptor.

Article Snippet: Concentrated Gas6 reagents were analyzed for concentration via Western blotting using a Gas6 standard (R&D Systems, 885-GSB-050).

Techniques: Construct, Expressing, Flow Cytometry, Staining, Concentration Assay, Control, Membrane, Phospho-proteomics, Western Blot

Journal: International journal of molecular sciences

Article Title: Regulation of Mertk Surface Expression via ADAM17 and γ-Secretase Proteolytic Processing.

doi: 10.3390/ijms25084404

Figure Lengend Snippet: Figure 6. Confocal imaging of the GFP-tagged MerTK construct displayed the differential localization of MerTK upon ligand stimulation and the inhibition of proteases. (A) DAPT and MG132 treatments induce increased cytoplasmic GFP signals compared to untreated cells. (B) Confocal imaging shows GFP localized on the cell membrane, indicating the presence of tagged Mertk constructs on the cell surface. γ-Carboxylated Gas6-treated tagged THP-1 cells showed a reduction in the MerTK construct from the membrane and the localization in lysosomes. (C) Quantification of the GFP fluorescence intensity per cell, calculated from confocal images in mock, γ-carboxylated Gas6, and non-γ-carboxylated Gas6, with the bar plots showing the mean and standard error of each treatment. ns; non-significant; *** p < 0.001; **** p < 0.0001.

Article Snippet: Concentrated Gas6 reagents were analyzed for concentration via Western blotting using a Gas6 standard (R&D Systems, 885-GSB-050).

Techniques: Imaging, Construct, Inhibition, Membrane, Fluorescence

Journal: International journal of molecular sciences

Article Title: Regulation of Mertk Surface Expression via ADAM17 and γ-Secretase Proteolytic Processing.

doi: 10.3390/ijms25084404

Figure Lengend Snippet: Figure 7. γ-carboxylation of Gas6 induces Mertk degradation independent of phosphorylation. (A) Mutants of the tagged construct were created. K619M, a substitution in the ATP-binding site (underlined) of the Mertk kinase domain, inhibits autophosphorylation by preventing ATP binding and the exchange of phosphate molecules. * Amino acid position for ADAM17 cleavage. (B) Constructs are treated with 10 nM ofGas6-VK for 30 min after a 6 h serum starvation. With the ability to bind ATP and phosphorylate, the WT construct becomes phosphorylated while the kinase dead K619M mutant does not. (C) Mutant constructs were treated with 3 µM of GW280264X (an ADAM17 inhibitor; GW), 5 µM of DAPT (a γ-secretase inhibitor), or 10 µM of MG132 (a protea- somal inhibitor) for 4 h. Results show that the absence of the K619M C-terminal fragment from the MG132 treatment with the addition of GW indicates the fragment is a product of cleavage. (D) Confocal images indicated that the K619M mutants have more cytoplasmatic c-Mertk than WT Mertk with MG132 treatment. (E) Comparison of the contrasting pathways between Notch Recep- tor and MerTK Signaling Models. In the absence of a ligand, Notch is not cleaved, while MerTK undergoes homeostatic cleavage, leading to proteasomal degradation. Upon ligand binding, Notch is cleaved at the ADAM 17 site, revealing the gamma-secretase site. Subsequent gamma-secretase cleavage releases the Notch intracellular domain, translocating it to the nucleus for transcriptional activation. Conversely, MerTK, upon ligand (Gas6) interaction, is internalized into endosomal compartments and localizes within lysosomes.

Article Snippet: Concentrated Gas6 reagents were analyzed for concentration via Western blotting using a Gas6 standard (R&D Systems, 885-GSB-050).

Techniques: Phospho-proteomics, Construct, Binding Assay, Mutagenesis, Comparison, Ligand Binding Assay, Activation Assay

Journal: Cells

Article Title: Gas6 Prevents Epithelial-Mesenchymal Transition in Alveolar Epithelial Cells via Production of PGE 2 , PGD 2 and Their Receptors

doi: 10.3390/cells8070643

Figure Lengend Snippet: Growth arrest-specific protein 6 (Gas6) pretreatment inhibits transforming growth factor (TGF)-β1-induced epithelial-mesenchymal transition (EMT) in lung epithelial cells (ECs). ( A – C ) LA-4 and ATII ECs were pretreated with 400 ng/mL Gas6 for 20 h prior to 10 ng/mL TGF-β1 treatment for 48 or 72 h. ( A ) Morphological changes in LA-4 ECs were examined by phase-contrast microscopy. Scale bars = 50 μm. Results are representative of three independent experiments. ( B ) Immunoblots of total cell lysates were performed with anti-E-cadherin, -N-cadherin, or -α-SMA antibodies. Densitometry of the relative abundances of the indicated EMT markers. Alpha-tubulin was used as a control. ( C ) The amount of EMT markers’ mRNAs in cell lysates was analysed by real-time PCR and normalized to that of hypoxanthine phosphoribosyltransferase. Values represent the mean ± S.E. of three independent experiments. * P < 0.05; compared with control; + P < 0.05 as indicated.

Article Snippet: Recombinant mouse Gas6 was purchased from R&D Systems (Minneapolis, MN, USA).

Techniques: Microscopy, Western Blot, Control, Real-time Polymerase Chain Reaction

Journal: Cells

Article Title: Gas6 Prevents Epithelial-Mesenchymal Transition in Alveolar Epithelial Cells via Production of PGE 2 , PGD 2 and Their Receptors

doi: 10.3390/cells8070643

Figure Lengend Snippet: Growth arrest-specific protein 6 (Gas6) pretreatment reduces epithelial-mesenchymal transition (EMT)-regulating transcription factor expression and blocks Smad-independent transforming growth factor (TGF)-β1 signalling in epithelial cells. ( A – C ) LA-4 and ATII epithelial cells (ECs) were pretreated with 400 ng/mL Gas6 20 h prior to 10 ng/mL TGF-β1 stimulation for 48 or 72 h. ( A , B ) The amounts of Snai1/2, Zeb1/2, and Twist1 mRNA were analysed by real-time PCR and normalized to that of hypoxanthine phosphoribosyltransferase ( Hprt ). ( C , D ) Representative immunoblots of LA-4 EC lysates were performed with anti-Snail1, -Zeb1, -total/phosphorylated ERK1/2, and -Akt protein antibodies. Beta-actin or alpha-tubulin was used as a loading control. Densitometric analysis of the indicated protein abundances. Data in all bar graphs are the mean ± S.E. of three independent experiments. * P < 0.05 compared with control; + P < 0.05 as indicated.

Article Snippet: Recombinant mouse Gas6 was purchased from R&D Systems (Minneapolis, MN, USA).

Techniques: Expressing, Real-time Polymerase Chain Reaction, Western Blot, Control

Journal: Cells

Article Title: Gas6 Prevents Epithelial-Mesenchymal Transition in Alveolar Epithelial Cells via Production of PGE 2 , PGD 2 and Their Receptors

doi: 10.3390/cells8070643

Figure Lengend Snippet: Cyclooxygenase (COX)-2 signaling is required for growth arrest-specific protein 6 (Gas6)-induced production of prostaglandin (PG)E 2 , PGD 2 , and their receptors. ( A – C ) LA-4 and primary alveolar type II (AT II) epithelial cells (ECs) were treated with 400 ng/mL Gas6 for the times indicated. ( A ) qPCR analysis of Cox2 and Cox1 mRNAs in cell lysates. ( B ) Representative immunoblots of LA-4 EC lysates were performed with anti-COX-2, -COX-1, or -α-tubulin antibodies. ( C ) PGE 2 or PGD 2 levels in conditioned media from LA-4 and AT II ECs were measured by enzyme immunoassay. ( D ) Immunoblots of total cell lysates were performed with anti-COX-2 antibodies in LA-4 ECs transfected with COX-2 specific or control siRNA for 6 h. Densitometric analysis of the COX-2 relative abundances. PGE 2 and PGD 2 levels in conditioned media from LA-4 ECs transfected with COX-2 specific or control siRNA for 6 h prior to treatment with 400 ng/mL Gas6 for 20 h were measured by EIA. ( E ) qPCR analysis of Ptger2, Ptger4, Dp1, and Dp2 mRNA in LA-4 ECs treated with 400 ng/mL Gas6 for the time indicated. ( F ) Immunoblot analysis of EP2, EP4, DP1, or DP2 in LA-4 cells. Densitometric analysis of the indicated receptor’ relative abundances. ( G ) qPCR analysis of Ptger2, Ptger4, Dp1, and Dp2 mRNA in LA-4 ECs transfected with COX-2 specific or control siRNA for 6 h prior to treatment with 400 ng/mL Gas6 for 20 h. ( H ) qPCR analysis of Ptger2, Ptger4, Dp1, and Dp2 mRNA in ATII ECs treated with 400 ng/mL Gas6 for the time indicated. Data in all bar graphs are the mean ± S.E. of three independent experiments. * P < 0.05 compared with control; + P < 0.05 as indicated.

Article Snippet: Recombinant mouse Gas6 was purchased from R&D Systems (Minneapolis, MN, USA).

Techniques: Western Blot, Enzyme-linked Immunosorbent Assay, Transfection, Control

Journal: Cells

Article Title: Gas6 Prevents Epithelial-Mesenchymal Transition in Alveolar Epithelial Cells via Production of PGE 2 , PGD 2 and Their Receptors

doi: 10.3390/cells8070643

Figure Lengend Snippet: Cyclooxygenase (COX)-2-derived signaling mediates growth arrest-specific protein 6 (Gas6)-induced epithelial-mesenchymal transition (EMT) inhibition. ( A – D ) LA-4 ECs were pretreated with 10 μM NS-398 1 h before 400 ng/mL Gas6 treatment for 20 h and then stimulated with 10 ng/mL TGF-β1 treatment for 72 h. ( A ) Morphological changes in the cells were examined by phase-contrast microscopy. Scale bars = 50 μm. ( B ) Immunoblots of total cell lysates were performed with anti-E-cadherin, -N-cadherin, or -α-SMA antibodies. Densitometric analysis of the indicated EMT markers’ relative abundances. ( C , D ) Primary AT II cells were pretreated with 10 μM NS-398 1 h before 400 ng/mL Gas6 treatment for 20 h and then stimulated with 10 ng/mL TGF-β1 treatment for 72 h. qPCR analysis of the mRNAs of EMT markers and EMT-regulating transcription factors. ( E , F ) LA-4 ECs were transfected with COX-2-specific or control siRNAs for 6 h prior to treatment with 400 ng/mL Gas6 for 20 h and then stimulated with 10 ng/mL TGF-β1 for 72 h or the times indicated. Representative immunoblots of LA-4 EC lysates were performed with anti-E-cadherin, -N-cadherin, -α-SMA, -total/phosphorylated ERK1/2, and -Akt protein antibodies. Densitometric analysis of the indicated protein abundances. Data in all bar graphs are the mean ± S.E. of three independent experiments. * P < 0.05 compared with control; + P < 0.05 as indicated.

Article Snippet: Recombinant mouse Gas6 was purchased from R&D Systems (Minneapolis, MN, USA).

Techniques: Derivative Assay, Inhibition, Microscopy, Western Blot, Transfection, Control

Journal: Cells

Article Title: Gas6 Prevents Epithelial-Mesenchymal Transition in Alveolar Epithelial Cells via Production of PGE 2 , PGD 2 and Their Receptors

doi: 10.3390/cells8070643

Figure Lengend Snippet: Prostaglandin (PG)E 2 and PGD 2 secretion inhibits growth arrest-specific protein 6 (Gas6)-induced epithelial-mesenchymal transition (EMT) via their receptors. ( A – D ) LA-4 and AT II epithelial cells (ECs) were stimulated with 400 ng/mL Gas6 for 20 h and then stimulated with 10 ng/mL TGF-β1 for 48 or 72 h with or without antagonists of EP2 (AH-6809), EP4 (AH-23848), DP1 (BW-A868C), or DP2 (BAY-u3405), each at a dose of 10 μM. ( A ) Representative immunoblots of total cell lysates were performed with anti-E-cadherin, -N-cadherin, or -α-SMA antibodies. ( B ) qPCR analysis of the mRNAs of EMT transcription factors in LA-4 ECs. ( C , D ) qPCR analysis of the mRNAs of EMT markers and EMT transcription factors in primary AT II ECs. Values represent the mean ± S.E. of three independent experiments. * P < 0.05 compared with control; + P < 0.05 as indicated.

Article Snippet: Recombinant mouse Gas6 was purchased from R&D Systems (Minneapolis, MN, USA).

Techniques: Western Blot, Control

Journal: Cells

Article Title: Gas6 Prevents Epithelial-Mesenchymal Transition in Alveolar Epithelial Cells via Production of PGE 2 , PGD 2 and Their Receptors

doi: 10.3390/cells8070643

Figure Lengend Snippet: Activation of Axl or Mer mediates growth arrest-specific protein 6 (Gas6)-induced inhibition of COX-2 signaling and epithelial-mesenchymal transition (EMT) in LA-4 epithelial cells (ECs). ( A , B ) Immunoblot of total cell lysates were performed with anti-total/phosphorylated Axl and -Mer antibodies in LA-4 ECs treated with 400 ng/mL Gas6 for the times indicated. Densitometric analysis of the indicated protein abundances. ( C , D ) Immunoblots of total cell lysates were performed with anti-Axl, or -Mer antibodies in LA-4 ECs transfected with Axl, Mer, or control siRNA. Densitometric analysis of the indicated protein abundances. ( E – G ) LA-4 ECs were transfected with Axl, Mer, or control siRNAs for 48 h and then stimulated with 400 ng/mL Gas6. ( E , G ) qPCR analysis of the mRNAs of Cox2, Ptger2, Ptger4, Dp1, and Dp2 in LA-4 EC lysates 1 or 20 h after Gas6 stimulation. ( F ) PGE 2 and PGD 2 levels in conditioned media 20 h after Gas6 stimulation were measured by enzyme immunoassay. ( H – J ) LA-4 ECs were transfected with Axl, Mer, or control siRNAs for 48 h prior to treatment with 400 ng/mL Gas6 for 20 h and then stimulated with 10 ng/mL TGF-β1 for 72 h or the times indicated. ( H ) Representative immunoblots of total cell lysates with anti-E-cadherin, -N-cadherin, or -α-SMA antibodies in the indicated samples. ( I ) qPCR analysis of the mRNAs of EMT transcription factors. ( J ) Representative immunoblots of total cell lysates with anti-total/phosphorylated ERK1/2 and -Akt protein antibodies. Values represent the mean ± S.E. of three independent experiments. * P < 0.05; compared with control; + P < 0.05 as indicated.

Article Snippet: Recombinant mouse Gas6 was purchased from R&D Systems (Minneapolis, MN, USA).

Techniques: Activation Assay, Inhibition, Western Blot, Transfection, Control, Enzyme-linked Immunosorbent Assay

Journal: Cells

Article Title: Gas6 Prevents Epithelial-Mesenchymal Transition in Alveolar Epithelial Cells via Production of PGE 2 , PGD 2 and Their Receptors

doi: 10.3390/cells8070643

Figure Lengend Snippet: Growth arrest-specific protein 6 (Gas6)/Axl signaling inhibits migration and invasion of LA-4 and alveolar type II (AT II) epithelial cells (ECs) via prostaglandin (PG)E 2 and PGD 2 . ( A – D ) LA-4 and primary AT II ECs were stimulated with 400 ng/mL Gas6 for 20 h and then stimulated with 10 ng/mL TGF-β1 with or without antagonists of EP2 (AH-6809), EP4 (AH-23848), DP1 (BW-A868C), or DP2 (BAY-u3405), each at a dose of 10 μM, for 48 or 72 h. The quantification of migrated or invaded cells in Boyden chambers. ( E , F ) LA-4 ECs were transfected with Axl, Mer, or control siRNAs for 48 h prior to treatment with 400 ng/mL Gas6 for 20 h and then stimulated with 10 ng/mL TGF-β1 for 72 h. The cells were visualized by phase-contrast microscopy for the analysis of migratory in ( E ) left and invasive in ( F ) left abilities using Fn-coated Transwell and Matrigel-coated Transwell plates, respectively. Scale bars: 100 μm. Quantification of cells that migrated in ( E ) right or invaded in ( F ) right. Values represent the mean ± S.E. of three independent experiments. * P < 0.05 compared with control; + P < 0.05 as indicated.

Article Snippet: Recombinant mouse Gas6 was purchased from R&D Systems (Minneapolis, MN, USA).

Techniques: Migration, Transfection, Control, Microscopy

Journal: Journal of Inflammation (London, England)

Article Title: The PPAR-γ antagonist GW9662 elicits differentiation of M2c-like cells and upregulation of the MerTK/Gas6 axis: a key role for PPAR-γ in human macrophage polarization

doi: 10.1186/s12950-015-0081-4

Figure Lengend Snippet: GW9662 induces M2c-like cells that upregulate MerTK and its ligand Gas6. (A-C) Healthy monocytes were cultured in serum-free medium in the absence of cytokines or growth factors (M0 differentiation), with or without the PPAR-γ antagonist GW9662 (2.5-10 μM), for 4 days; when specified, the PPAR-γ agonist rosiglitazone (1 μM) was added. Expression of MerTK, CD163 and CD16 was measured by flow cytometry. (D-E) Gas6 production levels were quantified by ELISA in culture medium, upon incubation with or without GW9662 (2.5-10 μM) of otherwise untreated cells (M0 conditions), LPS (50 ng/ml; M1 conditions) or IL-4 (20 ng/ml; M2a conditions) exposed cells. (A-E) Pooled data are represented as mean values ± SEM. Analysis was performed using one-way repeated measures ANOVA with Newman-Keuls multiple comparisons test. *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001. When not specified by additional graphic signs, statistical annotations (asterisks) refer to comparisons with respect to the relative GW9662 untreated control group. Each set of data is representative of three independent experiments.

Article Snippet: Biotinylated goat polyclonal anti-human Gas6 antibody (R&D Systems), followed by HRP-conjugated streptavidin (Biolegend), was used for detection.

Techniques: Cell Culture, Expressing, Flow Cytometry, Enzyme-linked Immunosorbent Assay, Incubation, Control

Journal: Mediators of inflammation

Article Title: Growth Arrest-Specific 6 Enhances the Suppressive Function of CD4 + CD25 + Regulatory T Cells Mainly through Axl Receptor.

doi: 10.1155/2017/6848430

Figure Lengend Snippet: Figure 6: Gas6 modulates the Foxp3 and CTLA4 expression mainly through Axl receptor. (a–d) CD4+CD25+Tregs were treated with anti- Axl or anti-Mertk Abs or PBS in the presence of 100 ng/ml rmGas6. After 24 h of incubation, the expression of CTLA-4 and Foxp3 was determined by flow cytometry (𝑛= 4/group). ∗𝑃< 0.05 compared with the value for the Gas6 group, and #𝑃< 0.05 compared with the value for rmGas6+anti-Mertk group. (e–h) The expression of CTLA-4 and Foxp3 in Tregs with or without Axl knockout was determined by flow cytometry. ∗𝑃< 0.05 compared with the value for the Gas6 group.

Article Snippet: To investigate the effect of Gas6 on CD4+CD25+Tregs in vivo, healthy mice were administered 1, 3, or 6 μg/mouse of rmGas6 (8310-GS, R&D Systems, Minneapolis, MN) via tail vein.

Techniques: Expressing, Incubation, Flow Cytometry, Knock-Out

Journal: Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry, and pharmacology

Article Title: Gas6 delays senescence in vascular smooth muscle cells through the PI3K/ Akt/FoxO signaling pathway.

doi: 10.1159/000373940

Figure Lengend Snippet: Fig. 2. Gas6 delays the senescence process in VSMCs. (A and B) Western blots demonstrating that cells trea- ȋʹͷͲȀȌ͵ϐ ͳ Ͷ and p21Cip1 expression. (C) The ef- fects of Gas6 on the IS and RS models were examined using western blotting. In the IS model, the Gas6-tre- ated cells showed low p21Cip1 and p16 Ͷ expression. In the RS model, the Gas6-treated cells also showed low p21Cip1 and p16 ͶǤȋȌǦȾǦ Ǧ ϐ Ǧ Ǧ RS models. (E and F) When these cells were treated with Axl-Fc, the levels of p16 Ͷ and p21Cip1 and the ǦȾǦ ϐ Ǥ (n=3 in each case). The values are presented as the mean±SD. *P<0.05, **P<0.01 and ***P<0.001 compared with the corresponding blank group; #P<0.05, ##P<0.01 and ###P<0.001 compared with the corresponding blank group. Bar, 200 μm.

Article Snippet: Recombinant mouse Gas6 (Gas6) protein and the recombinant mouse Axl-Fc protein fragment (Axl-Fc) were purchased from R&D Systems (St. Paul, MN, USA).

Techniques: Western Blot, Expressing

Journal: Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry, and pharmacology

Article Title: Gas6 delays senescence in vascular smooth muscle cells through the PI3K/ Akt/FoxO signaling pathway.

doi: 10.1159/000373940

Figure Lengend Snippet: Fig. 3. Axl is the primary receptor in the Gas6-mediated anti-senescence effect. (A) Western blotting and SA- ȾǦͳ Ͷ and p21Cip1ϐ in R428-treated cells regardless of Gas6 treatment compared with the two R428-free cell groups, whereas ϐ ͶʹͺǦ ǤȋȌǦȾǦ ͶʹͺǦ ϐ compared with the two R428-free cell groups. All the results shown are from representative experiments (n=3 in each case). The values are presented as the mean±SD. **P<0.01 and ***P<0.001 compared with the non-R428-treated group; ##P<0.01 and ###P<0.001 compared with the non-R428-treated group. Bar, 200 μm.

Article Snippet: Recombinant mouse Gas6 (Gas6) protein and the recombinant mouse Axl-Fc protein fragment (Axl-Fc) were purchased from R&D Systems (St. Paul, MN, USA).

Techniques: Western Blot

Journal: Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry, and pharmacology

Article Title: Gas6 delays senescence in vascular smooth muscle cells through the PI3K/ Akt/FoxO signaling pathway.

doi: 10.1159/000373940

Figure Lengend Snippet: Fig. 4. Gas6 promotes the transition from G1 to S phase. Cell cycle analyses showing that Gas6-treated cells in both the IS and the RS models showed higher percentages of S phase and a lower percentage of G1 phase Ǧ Ǧ Ǣȋ Ȍϐ with the corresponding controls. (B) EdU staining results showed that the positive staining rates in both the IS and the RS models after Gas6 treatment were higher than in controls. All the results shown are from representative experiments (n=3 in each case). The values are presented as the mean±SD. *P<0.05 compared with the non-Gas6-treated group; #P<0.05 compared with the non-Gas6-treated group.

Article Snippet: Recombinant mouse Gas6 (Gas6) protein and the recombinant mouse Axl-Fc protein fragment (Axl-Fc) were purchased from R&D Systems (St. Paul, MN, USA).

Techniques: Staining

Journal: Molecular Cancer Therapeutics

Article Title: Evaluation of the Role of AXL in Fusion-positive Pediatric Rhabdomyosarcoma Identifies the Small-molecule Inhibitor Bemcentinib (BGB324) as Potent Chemosensitizer

doi: 10.1158/1535-7163.mct-23-0285

Figure Lengend Snippet: Figure 2. Gas6 stimulates Axl signaling in FP-RMS cells. A, Representative Western blot images showing AXL expression in IC-pPDX-104 and Rh41 WT, KO (sgAXL-1) and OE lines. GAPDH was used as loading control. B, Morphologic appearance of IC-pPDX-104 and Rh41 cells with AXL WT, KO and OE. Scale bar, 70 mm. C, Schematic representation of the AXL signaling pathway. D, Representative Western blot images of AXL WT, KO (sgAXL-1) and OE cells stimulated with 400 ng/mL GAS6 for 10 minutes. E, Quantification of Western blots measuring the phosphorylation of downstream targets of AXL in AXL WT, KO (sgAXL-1) and OE cells stimulated with 400 ng/mL GAS6 for 10 minutes. Data are represented as mean SEM of the indicated number of independent biological replicates; ordinary two-way ANOVA with Sidak multiple comparisons test. ns, nonsignificant.

Article Snippet: The next day, we stimulated cells with the indicated concentration of GAS6 (R&D Systems, 885-GSB-050) for 10 minutes at 37 C, and processed them for Western blot analysis.

Techniques: Western Blot, Expressing, Control, Phospho-proteomics

Journal: Molecular Cancer Therapeutics

Article Title: Evaluation of the Role of AXL in Fusion-positive Pediatric Rhabdomyosarcoma Identifies the Small-molecule Inhibitor Bemcentinib (BGB324) as Potent Chemosensitizer

doi: 10.1158/1535-7163.mct-23-0285

Figure Lengend Snippet: Figure 5. Axl contributes to the migratory phenotype of Rh41 cells. A–C, Effect of AXL expression levels on the migratory phenotype of Rh41 cells. Representative images of Rh41 AXL WT (sgAAVS1), KO (sgAXL-1, sgAXL-2) and OE cells (A) and quantification (B) of wound-healing assay. Scale bar, 100 mm. C, Wound area remaining after 20 hours. D–F, Effect of bemcentinib on the migratory phenotype of Rh41 cells. Representative images (D) and quantification (E) of wound-healing assay performed on Rh41 WT cells treated with the indicated concentrations of bemcentinib. Scale bar, 100 mm. F, Wound area remaining after 12 hours in Rh41 cells. G and H, Effect of bemcentinib and AXL stimulation with GAS6 on the migratory phenotype of AXL KO cells. G, Quantification of wound-healing assay performed on Rh41 AXL WT (sgAAVS1) and KO (sgAXL-1, sgAXL-2) cells treated with the indicated concentrations of bemcentinib or with 400 ng/mL GAS6. H, Wound area remaining after 15 hours in Rh41 cells. Data are represented as mean þ SEM of n ¼ 3 biological replicates. Ordinary one-wayANOVA with Dunnett multiple comparison test againstthe control group (WT or 0 mmol/L bemcentinib).

Article Snippet: The next day, we stimulated cells with the indicated concentration of GAS6 (R&D Systems, 885-GSB-050) for 10 minutes at 37 C, and processed them for Western blot analysis.

Techniques: Expressing, Wound Healing Assay, Comparison, Control

Journal: bioRxiv

Article Title: Gas6 ameliorates intestinal mucosal immunosenescence to prevent the translocation of a gut pathobiont, Klebsiella pneumoniae , to the liver

doi: 10.1101/2023.01.19.524842

Figure Lengend Snippet: (A) Cytokine array analysis of the K. pneumoniae infection model based on the Transwell insert co-culture system consisting of Caco-2 cells and RAW264.7 macrophages. Quantification of Axl signals using a laser scanner. Data are presented as the mean ± SD. ** p < 0.01. (B and C) Secretion of Axl (B) and Gas6 (C) by Caco-2 cells or RAW264.7 macrophages. Culture supernatants or lysates of K. pneumoniae were added to Caco-2 cells or RAW264.7 macrophages for 12 h. The culture media were then collected for ELISA analysis of Axl or Gas6 levels. Data are presented as the mean ± SD. ** p < 0.01. (D) K. pneumoniae -infected Caco-2 cells grown on a Transwell insert in the presence or absence of RAW264.7 macrophages were immunostained with anti-Gas6 and anti-Axl antibodies. Scale bar = 50 μm.

Article Snippet: The apical side of Caco-2 cells grown on Transwell inserts were exposed for 3 h to 20 nM Axl inhibitor (R428) (Abcam), 1 μg of anti-Gas6 antibody (R&D Systems), or 1 μg of human recombinant Gas6 protein (R&D Systems) prior to K. pneumoniae infection.

Techniques: Infection, Co-Culture Assay, Enzyme-linked Immunosorbent Assay

Journal: bioRxiv

Article Title: Gas6 ameliorates intestinal mucosal immunosenescence to prevent the translocation of a gut pathobiont, Klebsiella pneumoniae , to the liver

doi: 10.1101/2023.01.19.524842

Figure Lengend Snippet: (A) Western blotting was performed to detect the expression of Axl, Gas6, ZO-1, and occludin in Caco-2 cells infected with K. pneumoniae in the presence of an Axl inhibitor (R428) or an anti-Gas6 antibody. Prior to K. pneumoniae infection, cells were treated for 3 h with Axl inhibitor (R428; 20 nM) or 1 μg of anti-Gas6 antibody. (B and C) Axl inhibitor (R428; 20 nM) or 1 μg of anti-Gas6 antibody were added to Caco-2 cells grown on the insert in in the presence or absence of RAW264.7 macrophages for 3 h prior to K. pneumoniae infection. Next, Caco-2 cells were immunostained with an anti-ZO-1 antibody (B), an anti-occludin antibody (B), and an anti- Klebsiella pneumoniae antibody (C). Scale bar = 50 μm. Immunostaining intensities of ZO-1 (B), occludin (B), and K. pneumoniae (C) were analyzed by ImageJ software. Data are presented as the mean ± SD. ** p < 0.01.

Article Snippet: The apical side of Caco-2 cells grown on Transwell inserts were exposed for 3 h to 20 nM Axl inhibitor (R428) (Abcam), 1 μg of anti-Gas6 antibody (R&D Systems), or 1 μg of human recombinant Gas6 protein (R&D Systems) prior to K. pneumoniae infection.

Techniques: Western Blot, Expressing, Infection, Immunostaining, Software

Journal: bioRxiv

Article Title: Gas6 ameliorates intestinal mucosal immunosenescence to prevent the translocation of a gut pathobiont, Klebsiella pneumoniae , to the liver

doi: 10.1101/2023.01.19.524842

Figure Lengend Snippet: (A and B) Sections of cecal mucosa (A) or liver (B) were from mice aged 15 or 57 weeks at 2 days after infection with K. pneumoniae ATCC43816 pmCherry and immunostained with an anti-Gas6 antibody and an anti-Axl antibody. Scale bar = 50 μm. (C) Detection of Axl, Gas6, ZO-1, and occludin by western blotting. Cecum and liver tissues were collected, homogenized, and analyzed using an anti-Axl antibody, an anti-Gas6 antibody, an anti-ZO-1 antibody, or an anti-occludin antibody. Signal intensity was analyzed by ImageJ software. Data are presented as the mean ± SD (n = 5 per group). NS: not significant, * p < 0.05, ** p < 0.01. (D) Linear correlation between Gas6 expression and Axl expression in the cecum or liver of mice aged 15 (red circles) or 57 (blue circles) weeks infected with K. pneumoniae ATCC43816 pmCherry. r > 0.70 and p < 0.05. (E) The population of CD11b+F4/80+ macrophages in the intestinal mucosa of young (14-week-old) and old (56-week-old) mice was examined by staining with anti-F4/80 and anti-CD11b antibodies. The percentage of F4/80-positive/CX3CR1-negative cells in 14-week-old and 56-week-old mice was 29.5% and 8.87%, respectively. Data are representative of four mice.

Article Snippet: The apical side of Caco-2 cells grown on Transwell inserts were exposed for 3 h to 20 nM Axl inhibitor (R428) (Abcam), 1 μg of anti-Gas6 antibody (R&D Systems), or 1 μg of human recombinant Gas6 protein (R&D Systems) prior to K. pneumoniae infection.

Techniques: Infection, Western Blot, Software, Expressing, Staining

Journal: bioRxiv

Article Title: Gas6 ameliorates intestinal mucosal immunosenescence to prevent the translocation of a gut pathobiont, Klebsiella pneumoniae , to the liver

doi: 10.1101/2023.01.19.524842

Figure Lengend Snippet: (A) Administration of Gas6 recombinant protein to Caco-2 cells to analyze the expression of Axl, ZO-1, and occludin. Addition of Gas6 recombinant protein to the apical surface (left scheme) or the basolateral side (right scheme) of Caco-2 cells. (B) Western blot analysis to detect Axl, Gas6, ZO-1, and occludin in Caco-2 cells treated with human Gas6 recombinant protein from the apical or basolateral sides. (C) Western blot analysis was performed to detect Axl, Gas6, ZO-1, and occludin. Gas6 recombinant protein (1 μg) was added to the apical side of Caco-2 cells grown in a Transwell co-culture system for 3 h prior to K. pneumoniae infection. (D and E) Gas6 recombinant protein (1 μg) was added to Caco-2 cells grown on the Transwell insert for 3 h prior to K. pneumoniae infection. Next, Caco-2 cells were immunostained with an anti-ZO-1 antibody (C), an anti-occludin antibody (C), an anti- Klebsiella pneumoniae antibody (D), and an anti-E-cadherin antibody. The signal intensities of ZO-1, occluding, E-cadherin, and K. pneumoniae were analyzed by ImageJ software. Data are presented as the mean ± SD. NS: not significant, ** p < 0.01.

Article Snippet: The apical side of Caco-2 cells grown on Transwell inserts were exposed for 3 h to 20 nM Axl inhibitor (R428) (Abcam), 1 μg of anti-Gas6 antibody (R&D Systems), or 1 μg of human recombinant Gas6 protein (R&D Systems) prior to K. pneumoniae infection.

Techniques: Recombinant, Expressing, Western Blot, Co-Culture Assay, Infection, Software

Journal: bioRxiv

Article Title: Gas6 ameliorates intestinal mucosal immunosenescence to prevent the translocation of a gut pathobiont, Klebsiella pneumoniae , to the liver

doi: 10.1101/2023.01.19.524842

Figure Lengend Snippet: (A) Treatment scheme used to analyze the effect of Gas6 recombinant protein on the susceptibility of 57-week-old mice to infection by K. pneumoniae . Antibiotics were administered 4 weeks before administration of Gas6 recombinant protein. Gas6 recombinant protein (125 μg protein/kg) was administered intraperitoneally to 57-week-old mice three times every 24 h prior to bacterial infection. (B) Effect of Gas6 recombinant protein on survival of 57-week-old mice infected with K. pneumoniae ATCC43816 pmCherry. Each mouse was orally inoculated with K. pneumoniae ATCC43816 pmCherry (5 × 10 7 bacteria). p -values were determined using the log-rank test (n = 6 per group). (C) Bacterial counts in cecum and liver tissues were determined 2 days post-infection. Cecum and liver tissues were homogenized in PBS. The homogenates were plated on LB agar containing 400 μg/mL ampicillin and the number of CFU was counted. Data are presented as the mean ± SD. (n = 6 per group). * p < 0.05, ** p < 0.01. (D) Detection of Axl, Gas6, ZO-1, and occludin by western blotting. Cecum tissues were collected, homogenized, and analyzed by western blotting with anti-Axl, anti-Gas6, anti-ZO-1, or anti-occludin antibodies. Signal intensity was analyzed by ImageJ software. Data are presented as the mean ± SD (n = 5 per group). NS: not significant, * p < 0.05, ** p < 0.01.

Article Snippet: The apical side of Caco-2 cells grown on Transwell inserts were exposed for 3 h to 20 nM Axl inhibitor (R428) (Abcam), 1 μg of anti-Gas6 antibody (R&D Systems), or 1 μg of human recombinant Gas6 protein (R&D Systems) prior to K. pneumoniae infection.

Techniques: Recombinant, Infection, Bacteria, Western Blot, Software