2851 CSAFLKE(1) VSACEKF(1) 2 Phage display (common panning) 4 PMID:24341921 B3β2γ Not determined. Not determined. Not determined. Acid-pp M13 phage display library (XSAX2KX) 2852 ISACEKF(2) CSAFLKD(1) 2 Phage display (common panning) 5 PMID:24341921 B3β2γ Not determined. Not determined. Not determined. Acid-pp M13 phage display library (XSAX2KX) 2853 CSAFLKE(3) CSAFLKD(2) VSALLKD(1) 3 Phage display (common panning) 6 PMID:24341921 B3β2γ Not determined. Not determined. Not determined. Acid-pp M13 phage display library (XSAX2KX) 2854 ASASQKS(1) QSAVYKA(1) LSACNKV(1) TSASLKV(1) GSAPPKS(1) 5 Phage display (common panning) 4 PMID:24341921 B3β2γ-variant1 Not determined. Not determined. Not determined. Acid-pp M13 phage display library (XSAX2KX) 2855 RSAVHKQ(1) 1 Phage display (common panning) 5 PMID:24341921 B3β2γ-variant1 Not determined. Not determined. Not determined. Acid-pp M13 phage display library (XSAX2KX) 2856 TSARLKL(1) TSARAKQ(1) 2 Phage display (common panning) 6 PMID:24341921 B3β2γ-variant1 Not determined. Not determined. Not determined. Acid-pp M13 phage display library (XSAX2KX) 2857 DWERPTPYELSI(7)[+++] TPRPTQYWLHL(1)[++++] SGLLPTPQTRPV(1)[+++] WPTSWEVTASFN(1)[++] DHARPTSVWLSR(1)[+] HGISEMWYLTPK(1)[+] 6 Phage display (common panning) 3 PMID:11750040 Anti-NTX monoclonal antibody BNTX21 BAG family molecular chaperone regulator 1 Not determined. Not determined. Ph.D.-12 phage display library (X12) Western blot +, relative reactivity with mAb BNTX21 obtained in immunoblot assays. 2858 NALWMPT(1)[+++] SANMPTN(1)[+++] YLGLTPM(1)[++] NRLWMPS(1)[++] NKVWPPS(1)[++] TSYTGPA(1)[++] NKAWFPN(1)[+] 7 Phage display (common panning) 3 PMID:11750040 Anti-NTX monoclonal antibody BNTX21 BAG family molecular chaperone regulator 1 Not determined. Not determined. Ph.D.-7 phage display library (X7) Western blot +, relative reactivity with mAb BNTX21 obtained in immunoblot assays. 2859 ACVWSWGWCQPTCGSCG(2) ACEPKDFSCVQDDHPCG(2) ACCWSEQVCHPQGDWCG(1) ACGGWLGCCHPQDPSCG(1) ACLWDAMCCFQDDHPCG(1) ACWQASQCCYFPDDWCG(1) ACHPQQGNCCYQTLPCG(1) ACHPQGDHCCENRESCG(1) ACNLWDPLCCHPQNTCG(1) ACESQFEWCFCNLQPCG(1) ACDNRWQTCSWWCWDCG(1) ACQVGYTNCRTPYCGCG(1) ACHPQDGRCQSLFECCG(1) ACVHGLWPCHPQGDQCG(1) ACQDWAPYCELLNHPCG(1) ACLVSDMRCPHPQAPRG(1) AVGQDLSCFSNTHPCGG(1) HPQ 17 Phage display (common panning) 2 PMID:23560397 Streptavidin Biotin Not determined. Not determined. CX6CX6C phage display library Phage of the library were cyclized by oxidation and then subjected to affinity selections with the model target streptavidin. For the selection of binders to streptavidin, the streptavidin beads (50 μL) were directly blocked. The HPQ motif was present in different positions of the peptides, preferentially following one of the cysteine residues. 2860 ACGLQPMACHPQNDNCG(1) ACVSWHGGCHPQGDICG(1) ACVQNLFTCHPQNAYCG(1) ACQPIQQDCQWHPQGCG(1) ACQQHPQNCTRTEGNCG(1) ACYWGNDLCHPQNTGWG(1) HPQ 6 Phage display (common panning) 2 PMID:23560397 Streptavidin Biotin Not determined. Not determined. CX6CX6C phage display library Phage of the library were cyclized by reaction with TBMB and then subjected to affinity selections with the model target streptavidin. For the selection of binders to streptavidin, the streptavidin beads (50 μL) were directly blocked. The HPQ motif was present in different positions of the peptides, preferentially following one of the cysteine residues. 2861 CCRERGCENMVCP(8)[4.3] CCLGRGCENHRCL(4)[7.7] MCNAYFAGDLC(2)[NT] LFQGACDTGRCA(2)[NT] CCREPPCYNPLCI(1)[73.8] CCGQAPCYLPACG(1)[299.7] WCSCTGCENGGCR(1)[82.7] SCGCRGCENRFCA(1)[118.8] QCPMDCCSRGLCW(1)[67.1] GCPDDCCSRGLCL(1)[50.3] YCSMDPCGTGRCR(1)[444.7] NCKYTLCSGVLW(1)[>1000] NCLYSGCLQVGCC(1)[>1000] YCNTARCGQAYCL(1)[>1000] CCRERGCEGQVCP(1)[NT] CCSERGCENVFCG(1)[NT] CCQGRGCENTWCV(1)[NT] CCLDRSCDGLMCI(1)[NT] GCCVSGCGYMSCG(1)[NT] YCPQDCCSRHLCM(1)[NT] SCVRGGCCGSACG(1)[NT] VCPQDGCAVCPCR(1)[NT] NCLFAGCLGSMCC(1)[NT] NCLFSACQGLTCC(1)[NT] NCTARSCASPDCC(1)[NT] GCGTGRCGQVWCT(1)[NT] VCVTARCQLQWCL(1)[NT] VCRLSYCSARTCP(1)[NT] DCLVTYCPQVRCQ(1)[NT] LCALRGCENRSCS(1)[NT] NCKYSLSASSDCQ(1)[NT] VCSIYFALGC(1)[NT] RCISSARMGTLCS(1)[NT] VCAVGGRLQENCL(1)[NT] RCDRCR(1)[NT] GCSVYFTCQ(1)[NT] R-[ED]-R-G-C-[ED]-N-x-V, P-C-Y-x-P, RGCEN, P-x-D-C-C-S-R-x-[LV], L-[YF]-S-G-C-L, TARCGQ 36 Phage display (common panning) 2 PMID:23560397 Urokinase-type plasminogen activator Not determined. Not determined. Not determined. XCX4CX4CX phage display library Inhibition assay The inhibition constants (Ki, μM) were determined by incubating different concentrations of bicyclic peptides with fixed concentration of human uPA (1.5 nM). NT denotes not tested. For the uPA selections, neutravidin-coated magnetic beads were used to immobilize the biotinylated human uPA. 2862 TCGVQACLSARCY(2)[12.9] NCRFSGCLQTMCV(2)[8.8] NCRFSGCGTVACV(1)[10.9] GCSDQACWSARCV(1)[10.5] NCKFSGCSVSVCH(1)[5.1] NCKFSGCPWELCI(1)[0.8] DCRWSSCTARTCA(1)[8.6] NCRFSGCVWAKCS(1)[NT] NCKFSGCQFLGCE(1)[NT] SCKFSGCHRKPCT(1)[NT] NCKFSACYLTTCY(1)[NT] NCTFTLCGLAPCG(1)[NT] SCLFTFCYFVPCN(1)[NT] NCRYSGCFDTPCI(1)[NT] GCQTSQCTARTCL(1)[NT] GCTESSCSARTCP(1)[NT] VCRQSDCSRRTCI(1)[NT] ECTASDCSARVCW(1)[NT] RCLPSWCSARTCF(1)[NT] RCLLSACTARACN(1)[NT] GCAQSVCTARYCE(1)[NT] ICSVLGCLSARCG(1)[NT] GCSVQACFSGRCT(1)[NT] PCGEQACYTARCR(1)[NT] LCLSQACWSARCA(1)[NT] VCVERGCSTARCR(1)[NT] LCADVSCATARCR(1)[NT] ECQDRSCPFTMCS(1)[NT] NCYFSNCGAHSAE(1)[NT] N-C-[RK]-F-S-G, R-x-S-x-C-[TS]-A-R-T, S-V-Q-A-C-x-[ST]-A-R 29 Phage display (common panning) 2 PMID:23560397 Urokinase-type plasminogen activator Not determined. Not determined. Not determined. XCX4CX4CX phage display library Inhibition assay The inhibition constants (Ki, μM) were determined by incubating different concentrations of bicyclic peptides with fixed concentration of human uPA (1.5 nM). NT denotes not tested. For the uPA selections, neutravidin-coated magnetic beads were used to immobilize the biotinylated human uPA. 2863 LPLGPHT[0.066 ± 0.002] TDHSMPP[0.155 ± 0.002] SSPPKSP[0.131 ± 0.002] 3 Phage display (common panning) 4 PMID:25515813 Fibroblast growth factor 23(180-205) Not determined. Not determined. Not determined. Ph.D.-7 phage display library (X7) ELISA Affinities of the positive phage clones to FGF23 were measured by phage ELISA. The OD values were measured at 450 nm with a reference wavelength of 655 nm and data shown were reproduced from Fig. 1 in the reference. The affinity value of control phage vcsM13 to FGF-23 is 0.002. The affinity value was presented as mean ± standard deviation. After four rounds of panning, three positive clones with higher affinity and specificity for FGF23 were selected from 20 clones detected and further subjected to sequencing. 2864 AAAPLAQPHMWA(4)[11.50 ± 0.56, 13.7] SSTTTSDKYLSA(2)[9.31 ± 1.46, 10.8] SNLHDNNTEKNV(1)[8.06, 9.3] 3 Phage display (common panning) 4 PMID:25826583 Tumor necrosis factor ligand superfamily member 13 Not determined. Not determined. Not determined. Ph.D.-12 phage display library (X12) ELISA Phage ELISA was used for identification of specific sAPRIL-binding phage. Clone 21 (sequence not shown) was used as a positive control. The fold change of the optical density was normalized to the positive control. Clones with an A450 that was at least 6 fold higher than the positive control were considered positive for sAPRIL binding. Besides, three binding peptides were synthesized and their binding affinity with sAPRIL was determined and compared with an unrelated polypeptide (HWDPFSLSAYFP) as a negative control using peptide ELISA. Data in the first column of affinity values were results for phage ELISA and reproduced from Fig. 1A in the reference. Data in the second column of affinity values were results for peptide ELISA and reproduced from Fig. 1B in the reference. The sAPRIL-BP1 (AAAPLAQPHMWA) had the highest binding affinity and was subsequently used in vitro to assess whether it was able to inhibit sAPRIL binding in the fixed human colorectal cancer cell line LOVO cells. sAPRIL-BP1 showed a dose-dependent inhibitory effect on sAPRIL binding to the LOVO cells. In vivo in a mouse colorectal challenge model, the sAPRIL-BP1 reduced the growth of tumor xenografts in nude mice by inhibiting proliferation and inducing apoptosis intratumorally. Moreover, in an in vivo metastasis model, sAPRIL-BP1 reduced liver metastasis of colorectal cancer cells. It might be a candidate for treating colorectal cancers that express high levels of APRIL. 2865 CTVRTSADC(5/29)[11-384] 1 Phage display (common panning) 4 PMID:25848940 Extradomain-B fibronectin (EDB-FN) Not determined. Not determined. Not determined. Ph.D.-C7C phage display library (CX7C) Surface plasmon resonance (SPR) SPR was performed characterize the interaction between CTVRTSADC and EDB using Biacore T100 (GE healthcare, Waukesha, WI). The binding data was analyzed using the Scatchard plot. Affinity (Kd, μM) was calculated by fitting data points into a linear trend line using Microsoft Office Excel software. Two binding sites were identified by fitting data from 1.9 μM to 7.8 μM or data from 15.6 μM to 250 μM. A tight binding site had an affinity of 11 μM, and a weak site was measured to have an affinity of 384 μM. A cyclic nonapeptide, CTVRTSADC (ZD2), was identified. Then a ZD2-Cy5 conjugate was synthesized to accomplish molecular imaging of prostate cancer in vitro and in vivo. ZD2-Cy5 demonstrated effective binding to up-regulated EDB-FN secreted by TGF-β-induced PC3 cancer cells following EMT. Following intravenous injections, the targeted fluorescent probe specifically bound to and delineated PC3-GFP prostate tumors in nude mice bearing the tumor xenografts. ZD2-Cy5 also showed stronger binding to human prostate tumor specimens with a higher Gleason score (GS9) compared to those with a lower score (GS 7), with no binding in benign prostatic hyperplasia (BPH). Thus, the ZD2 peptide is a promising strategy for molecular imaging and targeted therapy of prostate cancer. 2866 LPADEDHHFYWT(8)[2.85 ± 0.33][12.82 ± 1.73] LLQLTTTKRPIT(7)[5.80 ± 0.52][22.39 ± 2.30] QTHHTHLPIQRA(5)[3.54 ± 0.25][11.46 ± 0.42] TINSNTLNSTPP(5)[5.36 ± 0.99][10.10 ± 0.31] QKESSTHFMAIH(3)[3.61 ± 0.86][NT] SFPTMTENFYPR(3)[3.18 ± 0.63][NT] MHDASPQLYRGR(2)[4.28 ± 0.85][NT] MEDNDTHWARMA(2)[3.07 ± 0.13][NT] TMYEPTTTRSPA(1)[2.72 ± 0.28][NT] SVTAGMPNRSNR(1)[3.85 ± 0.76][NT] HLSVAKKPLHRP(1)[2.20 ± 0.24][NT] WPGLLGTTSPNI(1)[2.32 ± 2.46][NT] VHWPASQPVQIP(1)[2.24 ± 0.26][NT] HDHNTNDMTLNA(1)[2.70 ± 0.08][NT] 14 Phage display (subtractive panning) 4 PMID:25886968 Esophageal squamous carcinoma cell Eca-109 Not determined. Not determined. Not determined. Ph.D.-12 phage display library (X12) ELISA,Fluorescence Evaluation of the binding selectivity of 60 phage clones were performed by cellular ELISA. Eca-109 and HEK293 cells were used in ELISA. The 96-well plates were measured at 450 nm using an ELISA reader (Bio-Tek ELX800, USA). Irrelevant phage clone (IRP, an amplified phage randomly selected from the original phage peptide library) and PBS were used as control groups. Binding was showed as a ratio of cancer/normal cell binding. Data in the first column of affinity values were reproduced from Fig. 1 in the reference and expressed as mean ± the standard deviation of three replicates. The values for IRP and PBS are 1.25 ± 0.10 and 1.05 ± 0.30, respectively. In addition, cell immunofluorescence assay was performed. Fluorescence images were observed using laser scanning confocal microscope (LSCM, Leica, Germany). Fluorescence signal intensity (IOD/Area) in the second column of affinity values was reproduced from Fig. 2B in the reference. Fluorescence signal intensity for IRP and PBS controls is 3.66155 ± 0.21256 and 2.04334, respectively. NT denotes not tested. Phages were firstly incubated with HEK293 cells. After incubation, the supernatant containing unbound phages was incubated with the blocked Eca-109 cells. The 60 randomly selected phage clones were tested using cellular enzyme-linked immunosorbent assay (ELISA), and 41 phage clones were identified as positive clones with the over 2.10 ratio of absorbance higher than other clones, IRP and PBS controls. From the sequencing results of the positive clones, 14 peptide sequences were obtained and LLQLTTTKRPIT (ESCP9) consensus sequence was identified as the peptide with best affinity to ESCC cells via competitive inhibition, fluorescence microscopy, and flow cytometry. The results indicate that the peptide ESCP9 can bind to ESCC cells specifically and sensitively, and it is a potential candidate to be developed as an useful molecule to the imaging detection and targeting therapy for ESCC. 2867 QTTHRNWA (8) HTSHRNWD (4) FPHPWNPP (3) YPHPWNPT (3) PRYLPWFP (2) 5 Phage display (subtractive panning) 3 PMID:23394544 Anti-aflatoxin monoclonal antibody 1C11 Aflatoxin B1 Not determined. Not determined. CX8C M13 phage display library To eliminate nonspecific binding of phage with BSA, phages were firstly incubated with plate coated with BSA-PBS. After incubation, the supernatant containing unbound phages was incubated with the the plate containing 1C11 MAb. To elute the bound phage, 100 μL AFB1 (100 ng/mL in 10% methanol, competitive elution) was added to each well with shaking for 30 min to compete the binding phage from the coating antibody. 2868 LHSKHTYE(12)[13.9, 0.174] PTKAGIQS(5)[28.7, 0.087] PNPKSKTI(3)[44.3, 0.055] 3 Phage display (subtractive panning) 3 PMID:25908560 Anti-thiacloprid monoclonal antibody 3A5 Thiacloprid Not determined. Not determined. CX8C M13 phage display library Competition experiment The evaluations of the phage-displayed peptides were based on the IC50 (ug/L) and Amax/IC50 (the ratio of Amax to IC50), the combination of low IC50 and high Amax/IC50 was the most desirable. To eliminate nonspecific binding of phage to BSA, phages were firstly incubated with plate coated with BSA-PBS. After incubation, the supernatant containing unbound phages was incubated with the the plate containing 3A5 mAb. To elute the bound phage using competitive elution, 100 μL of thiacloprid (10 mg/L in PBS) was added to each well with shaking for 1 h to compete the binding phage from the coating antibody. 2869 LEIRSTVV(8)[55.7, 0.044] EYQYQTGL(7)[77.9, 0.031] AKSLEIDQ(5)[20.5, 0.118] 3 Phage display (subtractive panning) 3 PMID:25908560 Anti-thiacloprid monoclonal antibody 3A5 Thiacloprid Not determined. Not determined. X8 M13 phage display library Competition experiment The evaluations of the phage-displayed peptides were based on the IC50 (ug/L) and Amax/IC50 (the ratio of Amax to IC50), the combination of low IC50 and high Amax/IC50 was the most desirable. To eliminate nonspecific binding of phage to BSA, phages were firstly incubated with plate coated with BSA-PBS. After incubation, the supernatant containing unbound phages was incubated with the the plate containing 3A5 mAb. To elute the bound phage using competitive elution, 100 μL of thiacloprid (10 mg/L in PBS) was added to each well with shaking for 1 h to compete the binding phage from the coating antibody. 2870 VRFNDL[1.89] TRLNDL[1.93] TRIQDIN[1.94] TRINDV[1.95] TRVQDLPNW[2.06] TRMNDLKS[1.93] ERINDLTD[2.1] LRLNDLNTY[2.13] RYNDIEQH[1.9] LRINDLT[1.86] RWNDISE[1.89] SRVYDIL[1.94] NRINDFSD[2.02] T-R-I-N-D-L-T 13 Phage display (common panning) 3 PMID:25936577 Anti-GapC (1-150) mAb 1F2 Glyceraldehyde-3-phosphate dehydrogenase (EC:1.2.1.12) Not determined. Not determined. Ph.D.-12 phage display library (X12) ELISA The binding activities of 13 positive phage clones to the mAb1F2 were measured by sandwich ELISA. The OD values at 405 nm were measured and data shown were reproduced from the Fig. 3 in the reference. Wild-type M13 phage was used as a negative control, which had the value of 0.21 when binding to the mAb1F2. Amino acid sequence of the motif exactly matched 30TRINDLT36 of the S. dysgalactia GapC. Subsequently, site-directed mutagenic analysis further demonstrated that residues R31, I32, N33, D34 and L35 formed the core of 30TRINDLT36, and this core motif was the minimal determinant of the B-cell epitope recognized by the mAb1F2. The epitope 30TRINDLT36 showed high homology among different streptococcus species. Overall, our findings characterized a conserved B-cell epitope, which will be useful for the further study of epitope-based vaccines. 2871 AWTCSSRLCELG[0.2 ± 0.02] AQRYCTQSVCVW[0.56 ± 0.01] VCNEAVCYIESW[0.51 ± 0.02] AVCDALWCAFTA[0.88 ± 0.02] VGTCDDRWCVIR[1.28 ± 0.01] AYNCLHPTLCLI[1.22 ± 0.02] VCNSLWCTLPVG[0.86 ± 0.02] QNMFCSIATKSC[0.77 ± 0.02] C-D-x(2)-W-C 8 Phage display (common panning) 4 PMID:25944706 His-tagged porcine reproductive and respiratory syndrome virus (PRRSV) nonstructuralprotein (nsp) 7 Not determined. Not determined. Not determined. Ph.D.-12 phage display library (X12) ELISA The binding activities of phage clones encoding peptides with high binding affinities to His-tagged nsp7 proteins were identified by ELISA. The OD values at 450 nm were measured and data shown were reproduced from the Fig. 2 in the reference. The experiments were performed in triplicate and presented as mean ± standard deviation. Uncorrelated phage was served as the control, which had the value of 0.06 ± 0.02 when binding to the hHMGR protein. 2872 AQRYCTQSVCVW[0.56 ± 0.01] AVCDALWCAFTA[0.88 ± 0.02] VGTCDDRWCVIR[1.28 ± 0.01] AYNCLHPTLCLI[1.22 ± 0.02] VCNSLWCTLPVG[0.86 ± 0.02] QNMFCSIATKSC[0.77 ± 0.02] C-D-x(2)-W-C 6 Phage display (common panning) 5 PMID:25944706 His-tagged porcine reproductive and respiratory syndrome virus (PRRSV) nonstructuralprotein (nsp) 7 Not determined. Not determined. Not determined. Ph.D.-12 phage display library (X12) ELISA The binding activities of phage clones encoding peptides with high binding affinities to His-tagged nsp7 proteins were identified by ELISA. The OD values at 450 nm were measured and data shown were reproduced from the Fig. 2 in the reference. The experiments were performed in triplicate and presented as mean ± standard deviation. Uncorrelated phage was served as the control, which had the value of 0.06 ± 0.02 when binding to the hHMGR protein. 2873 VCNEAVCYIESW[0.51 ± 0.02] AVCDALWCAFTA[0.88 ± 0.02] VGTCDDRWCVIR[1.28 ± 0.01] AYNCLHPTLCLI[1.22 ± 0.02] VCNSLWCTLPVG[0.86 ± 0.02] C-D-x(2)-W-C 5 Phage display (common panning) 6 PMID:25944706 His-tagged porcine reproductive and respiratory syndrome virus (PRRSV) nonstructuralprotein (nsp) 7 Not determined. Not determined. Not determined. Ph.D.-12 phage display library (X12) ELISA The binding activities of phage clones encoding peptides with high binding affinities to His-tagged nsp7 proteins were identified by ELISA. The OD values at 450 nm were measured and data shown were reproduced from the Fig. 2 in the reference. The experiments were performed in triplicate and presented as mean ± standard deviation. Uncorrelated phage was served as the control, which had the value of 0.06 ± 0.02 when binding to the hHMGR protein. 2874 SGVYKVAYDWQH(16)[2.77 ± 0.29] GFPTRFEALSSN(2)[1.57 ± 0.25] VHWDFRQWWQPS(2)[1.52 ± 0.1] HTSSLWHLFRST(2)[2.25 ± 0.2] GLHTSATNLYLH(1)[2.23 ± 0.41] HSFKWLDSPRLR(1)[2.57 ± 0.12] SGVYKVAYDGQH(1)[2.3 ± 0.18] KASGSPSGFWPS(1)[3.1 ± 0.59] RRVDKVQYDRQH(1)[1.51 ± 0.12] GLHTSALSDLH(1)[NT] 10 Phage display (subtractive panning) 4, 5 PMID:25955351 Cation-independent mannose-6-phosphate receptor Insulin-like growth factor II 2L29 ,2V5P , Not determined. Ph.D.-12 phage display library (X12) ELISA Binding of the phages to IGF2R and BSA was examined with phage ELISA. The binding ratio OD450(IGF2R)/OD450(BSA) was calculated and data shown were reproduced from the Figure 3B in the reference. The phage with no insert peptide was served as the control, which had the value of 0.89 ± 0.11. The experiments were performed in triplicate and presented as mean ± standard deviation. NT denotes not tested. The first, third, and fifth rounds of biopanning were conducted on recombinant human IGF2R protein, while the second and fourth rounds of biopanning were conducted against rat hepatic stellate cells HSC-T6. Among the identified peptide candidates, peptide VHWDFRQWWQPS shows the highest binding affinity and specificity to recombinant human IGF2R protein and HSCs. The equilibrium dissociation constant (Kd) of peptide-431 is 6.19 μM for LX-2 cells and 12.35 μM for rat hepatic stellate cells HSC-T6. Cellular uptake of peptide-431 in LX-2 cells is significantly reduced after silencing IGF2R with siRNA. Peptide VHWDFRQWWQPS also enhances the uptake of a proapoptotic peptide (KLA peptide) in LX-2 and HSC-T6 cells, indicating that peptide VHWDFRQWWQPS can be used as a targeting ligand to deliver antifibrotic agents into not only rat but also human HSCs. Dimerization of peptide VHWDFRQWWQPS further increase its binding affinity to LX-2 cells by approximately 9-fold. 2875 YLDAWENEVINF[0.77 ± 0.06] YGDRWFMPVMRS[1.38 ± 0.11] DGYNGEPWIWQQ[0.77 ± 0.04] YAGDFWDLDALA[1.55 ± 0.004] WGYDWWENRSLT[0.11 ± 0.1] 5 Phage display (common panning) 3 PMID:25998380 Anti-TIM polyclonal antibody (pAb) Corticoliberin 3EHT ,3EHU , Not determined. Ph.D.-12 phage display library (X12) ELISA The binding activities of positive phage clones to EC187 were measured by sandwich ELISA. The OD values at 450 nm were read. The experiments were presented as mean ± standard deviation. After 3-round biopanning, positive clones were selected and the polypeptides carried by them were identified. 5 polypeptides were found to bind with the target specifically. Among them, the peptide YAGDFWDLDALA exhibited the highest affinity. By evaluating the cAMP accumulation in the CRFR1 or CRFR2-expressing HEK293 cells, we demonstrated that peptide YAGDFWDLDALA blocking the function of CRFR1, but not CRFR2. In addition, we also found that P7 and CRF act on CRFR1 competitively.