Construction, expression and characterization of human interferon α2b-(G4S)n-thymosin α1 fusion proteins in Pichia pastoris

AIM:Interferon α2b (IFNα2b) and thymosin α1 (Tα1) exhibit synergic effects in the treatment of hepatitis B and hepatitis C when used together. For developing a fusion protein drug, fusion proteins of IFNα2b and Ta1 linked by different lengths of (G4S)n(n = 1-3) were constructed and expressed in Pichia pastoris. METHODS: Using PCR and molecular clone techniques, the fusion genes of IFNα2b-(G4S)n-Tα1 (n = 1-3) were constructed and subcloned into the eukaryotic expression vector pPIC9. After transformation of these plasmids into P. pastoris, the expressed fusion proteins IFNα2b-(G4S) n-Tα1 (n = 1-3) were obtained. These proteins were purified through diethylaminoethyl (DEAE) affinity chromatography and Superdex?75 gel filtration and analyzed by SDS-PAGE and Western blot. Antiviral and E-rosette assays were used to investigate the bioactivities of these fusion proteins. RESULTS: DNA sequencing confirmed that the fusion genes of IFNa2b-(G4S)n-Tα1 (n= 1-3) were correctly cloned to the pPIC9 vector. The recombinant IFNα2b-(G4S)n-Tα1 (n = 1-3) fusion proteins expressed in P. pastoris were purified with DEAE and Superdex?75 gel filtration chromatography. The fusion proteins could be observed on sodium dodecylsulfate-polyacrylamide gel electrophoresis with molecular weight (MW) of 23.2, 22.9, and 22.6 ku, respectively, and reacted to the IFNa2b monoclonal antibody and Tal polyclonal antibody. The purified fusion proteins exhibit antiviral activity and can enhance the percentage of E-rosette-forming-cell in E-rosette assay. CONCLUSION: The recombinant IFNa2b-(G4S)n-Tα1 (n = 1-3) fusion proteins were successfully expressed in P. pastoris. Purified fusion proteins exhibit both antiviral activity of IFNa2b and immunomodulatory activity of Tal in vitro. These results will be the basis for further evaluation of the fusion proteins' function in vivo.

GST Fusion Protein Based Specific Polyclonal Antibody Preparation of Mouse Aquaporin 1

Aquaporins（AQPs） are specific membrane channels for water and other small nonionic molecules.In order to overcome the difficulties to generate the effictive antibody of membrane protein,we selected the cytoplasmic C-terminus of Aquaporin 1（AQP1） as an unique antigen.The long C-terminus of mouse AQP1 was overexpressed in the Glutathione S-tansferase Gene Fusion System.On the basis of the resonable amounts of soluable membrane protein peptides,we prepared the specific antibody.To pursure this object,we constructed pGEX-4T-1/mAQP1（DNA sequence from 700 to 801 bp） recombinant plasmid and transformed it into Escherichia coli BL21 cells.The GST-AQP1 C-terminal hydrophilic peptide fusion protein was induced by IPTG and further purified by Glutathione Sepharose 4B to obtain the right size fusion protein.Then we immunized the New Zealand rabbits to prepare the antiserum.The purified AQP1 antibody showed high sensitivity by ELISA assay and high specificity by Western blot with AQP1 null mice served as negative control.Finally,we also checked the AQP1 localization in the mouse renal tissues in wild type of mice and AQP1 null mice served as negative control.We demonstrated that AQP1 was highly expressed at the descending limb of Henle tube using our purified AQP1 antibody,which was consistent with previous report.The successful design and preparation of AQP1 antibody through GST technique is an example as making antibodies against a specific membrane protein.

Construction,Expression and Purification of SUMO1-GST Fusion Protein

Sumoylation is an important protein modification discovered recently. SUMO（small ubiquitin-related modifier） pathway regulates the protein stability and transcriptional activity with a 12-kDa small molecular protein, SUMO, ligated to the target protein. The purification of SUMO proteins is a key step to reveal their function. The purpose of this study was to construct the recombinant SUMO1 gene cloned to a pGEX-4T-1 vector to express and purify the SUMO1-GST fusion protein in Escherichia coli. First, the full length DNA sequence of SUMO1 gene was amplified by PCR and was ligated to pMD18-T vector. Then the SUMO1 gene was subcloned to pGEX-4T-1 prokaryotic expression vector between BamHI and XhoI sites, and transformed in Escherichia coli DH5α cells. The right colonies were identified by restrictive enzyme digestion and sequencing. The correct rebombinant plasmid of pGEX-4T-1-SUMO1 was transformed in Escherichia coli BL21 cells and then induced by IPTG（isopropyl- β-D-1- thiogalacto-pyranoside） to express the SUMO1-GST fusion protein. The highly purified SUMO1-GST（glutathione S-transferase） fusion protein was obtained by affinity chromatography. Finally, the properties of SUMO1-GST fusion protein were confirmed by Coomassie brilliant blue strain and Western blot analysis. The recombinant plasmid of pGEX-4T-1-SUMO1 was successfully constructed, and SUMO1-GST fusion proteins were successfully expressed.

Expression and characterization of Mac-1-FP fusion protein in CHO cells

Objective: To construct mammalian cell expression vectors for Mac-1 with CFP and YFP and apply FRET to study the dimerization and function of CD11 b( Mac-1 α subunit) and CD18(Mac-1 β subunit). Methods: The mammalian cell expression vector for CD11b fused with CFP at the carboxyl terminal was constructed to create recombinant plasmid of pCD11b-CFP. Then pCD11b-CFP was co-transfected with pYFP-CD18 into CHO cell, a fibroblast like cell line, as a target cell within which there are some signal pathways involved in inflammatory stimulation but without endogenous Mac-1. Then CHO cells stably expressing both CD11b-CFP and YFP-CD18 fusion proteins were selected by Western blot and laser scanning confocal microscope. Results: The cyan and yellow fluorescence in co-transfected positive CHO cells were observed under a fluorescence microscope. CHO-Mac-1-FP cells stably expressing both CD11b-CFP and YFP-CD18 fusion proteins were obtained as demonstrated by Western blot successfully. The adhesive activity of CHO-Mac-1-FP cells with CHO-1CAM-1 cells was increased markedly by treatment with PMA, suggesting the translocation of GD11b-CFP and YFP-CD18 to the plasma membrane in CHO-Mac-1-FP cells and dimerization of CD11b-CFP and YFP-CD18 just as the function of the wild type Mac-1. Conclusion: CHO-Mac-1-FP cells with adhesive activity are established successfully, thus CHO-Mac-1-FP cells may be useful for the study of Mac-1 by FRET and for other purposes.

XCL1/Glypican-3 fusion protein induces potent CD8^+ T-cell generation and enhances the anti-PD1 effect to suspend hepatocellular carcinoma development

Objective:To induce potent CD8^+T-cells against glypican-3(GPC3),which is overexpressed in hepatocellular carcinoma(HCC),to suspend tumor development.Methods:Since the chemokine receptor XCR1 is selectively expressed on professional cross-presenting CD8α^+dendritic cells(DCs).

Roles of low?density lipoproteinreceptor?related protein 1 in tumors

Low-density lipoprotein receptor-related protein 1(LRP1,also known as CD91),a multifunctional endocytic and cell signaling receptor,is widely expressed on the surface of multiple cell types such as hepatocytes,fibroblasts,neurons,astrocytes,macrophages,smooth muscle cells,and malignant cells.Emerging in vitro and in vivo evidence demonstrates that LRP1 is critically involved in many processes that drive tumorigenesis and tumor progression.For example,LRP1 not only promotes tumor cell migration and invasion by regulating matrix metalloproteinase(MMP)-2and MMP-9 expression and functions but also inhibits cell apoptosis by regulating the insulin receptor,the serine/threonine protein kinase signaling pathway,and the expression of Caspase-3.LRPI-mediated phosphorylation of the extracellular signal-regulated kinase pathway and c-jun N-terminal kinase are also involved in tumor cell proliferation and invasion.In addition,LRP1 has been shown to be down-regulated by microRNA-205 and methylation of LRP1CpG islands.Furthermore,a novel fusion gene,LRP1-SNRNP25,promotes osteosarcoma cell invasion and migration.Only by understanding the mechanisms of these effects can we develop novel diagnostic and therapeutic strategies for cancers mediated by LRP1.

Stability improvement of human collagenα1(I)chain using insulin as a fusion partner

To enhance the stability of recombinant human collagen α1(I) chains(rhCOL1 A1) in production and purification stages, a gene fragment fusing COL1 A1 and insulin protein coding domains was synthesized and inserted into the pPIC9 K expression vector. The fusion peptide-expressing Pichia pastoris strain was created by transformation.After optimization of shake flask cultures, the ultimate intracellular expression level of the insulin-collagen α1(I) chain fusion protein(INS-COL1 A1) reached about 300 mg·L^(-1), and no obvious protein degradation was found in the fermentation and purification processes. The His-tagged recombinant fusion protein was detected by western blotting and was effectively purified using Ni^(2+)-chelating chromatography. A prominent improvement in the stability of INS-COL1 A1 was observed compared to rhCOL1 A1 in vitro, and the rhCOL1 A1 released from the fusion protein was studied by LC–MS/MS and in bioassays. The results showed that the purified rhCOL1 A1 was consistent with the native protein in amino acid composition and had a similar biological compatibility. To our knowledge, this is the first study to demonstrate the use of insulin as a fusion protein to improve the stability of easily degradable proteins.

Expression of GST-IL-1 fusion gene

Two GST-IL-1 fusion genes were constructed by inserting different cDNA fragments of human interleukin1 (IL-1) into the 3'-terminus of GST gene in the fusion protein expression vector pGEX-4T. After IPTG induction ,SDS-PAGE was employed to detect the gene expression. No corresponding protein encoded by GST gene fused with the whole-length 816 bp IL-1 cDNA was observed, nor was free GST protein. However, the fusion protein of GST and IL-1 cDNA without the 189 bp at the 5'- terminus was detected, amounting to 30% of the total bacterial protein expressed. This might suggest that the sequence of 1-189 bp of IL-1 cDNA affected the expression of the fusion gene. That is to say, the downstream sequence distant from the translation start codon AUG in the target gene could significantly affect the expression of the fusion gene.

TIM-1-Fc融合蛋白对哮喘小鼠Th1/Th2和Th17/Treg免疫失衡的调节

目的制备T细胞免疫球蛋白和黏蛋白结构域1(T cell immunoglobulin domain and mucin domain protein-1,TIM-1)-Fc融合蛋白并探讨TIM-1-Fc融合蛋白对卵白蛋白(ovabumin,OVA)诱导的哮喘小鼠的干预作用及潜在作用机制。方法通过基因工程技术获得TIM-1-Fc融合蛋白。采用腹腔注射OVA氢氧化铝溶液致敏建立过敏性哮喘小鼠模型,随机分为对照组、哮喘组和TIM-1-Fc干预组。每次干预前20 min,使用40μL卵白蛋白生理盐水溶液(OVA-NS)滴鼻,TIM-1-Fc融合蛋白干预包括TIM-1-Fc滴鼻组(每只小鼠每次给予1μg/40μL TIM-1-Fc滴鼻)和TIM-1-Fc注射组(每只小鼠每次给予6μg/200μL TIM-1-Fc腹腔注射),每天1次,连续7 d,对照组用生理盐水替代。采用苏木精-伊红(HE)染色观察肺组织病理变化;采用流式细胞术检测小鼠外周血中辅助性T细胞2(type 2 T helper cells,Th2)、辅助性T细胞17(type 17 T helper cells,Th17)和调节性T细胞(Treg)比例及相关细胞因子水平。结果成功构建TIM-1-Fc融合蛋白,成功构建OVA诱导的过敏性哮喘小鼠模型。与哮喘组相比,TIM-1-Fc融合蛋白干预后显著减轻了哮喘小鼠气道炎性损伤和肺组织损伤;TIM-1-Fc融合蛋白干预能显著降低外周血中TIM-1^(+)CD4^(+)T细胞和TIM-1^(+)Th17细胞比例,使TIM-1^(+)Treg细胞增多,显著降低Th2、Th17细胞比例,提高Treg细胞比例,调节哮喘中Th1/Th2和Th17/Treg免疫失衡。结论TIM-1-Fc融合蛋白改善OVA诱导的过敏性哮喘小鼠气道炎症和肺组织损伤,其作用机制可能与TIM-1-Fc融合蛋白对Th1/Th2和Th17/Treg的免疫调节有关。

蛋白激酶全抑制分析揭示KG-1细胞增殖的分子机制

目的:通过分析KG-1细胞对各种蛋白激酶抑制剂的反应,探讨其增殖的分子机制。方法:采用CCK-8法、实时荧光定量PCR(qRT-PCR)和Western-blot检测各种蛋白激酶抑制剂对KG-1细胞增殖、相关基因mRNA表达水平以及FGFR1下游信号通路蛋白磷酸化水平的影响。结果:NVP-BGJ398和PD173074有效抑制KG-1细胞的增殖,表明FGFR及其下游信号通路在KG-1细胞增殖过程中具有关键作用。使用FGFR抑制剂处理后,p-FGFR1和p-STAT5水平显著下降(P<0.001),p-Akt水平稍有下降(P<0.05),并未影响p-ERK水平(P>0.05)。结论:FGFR1OP2-FGFR1主要作用于下游STAT5信号通路,以促进细胞增殖。蛋白激酶全抑制分析是一种可靠而直接的方法,可用于确定癌细胞增殖的分子机制。

Mechanisms of microRNA-150, cyclin B1 and mitochondrial-associated protein 2 in regulating apoptosis and inhibiting invasion and migration of Huh-7 hepatocellular carcinoma cells

Objective: To explore the mechanisms of microRNA-150, cyclin B1 and mitochondrial-associated protein 2 in regulating the apoptosis and inhibiting the invasion and migration of Huh-7 cells. Methods: Huh-7 cells were divided into the control group, the negative control group (NC group) and the miR-150 overexpression group (mimic group). The miR-150 overexpressing cell line was constructed by plasmid transfection. The cell viability and apoptosis were detected by cell counting kit-8 and flow cytometry. The cell migration and invasion capacity were measured by cell wound scratch assay and Transwell. The levels of miRNA and mRNA were detected by real-time quantitative polymerase chain reaction and the relative expression levels of proteins were detected by Western blot. Results: MiR-150 significantly inhibited the cell viability of Huh-7 and promoted its apoptosis (P<0.01). After 24 h of cultivation, the mobility of the control group and the NC group were (83.54±4.66)%and (85.57±4.74)%, respectively. The mobility of the mimic group was (49.63±3.78)%, which was significantly lower than that of the control group and the NC group (P<0.01). After 24 h of cultivation, the invasive rate of the control group and the NC group were (100.56±2.87)%and (101.63±3.74)%, respectively, and the invasive rate of mimic group was (51.63±5.32)%, which was significantly lower than that of the control group and the NC group (P<0.01). The expression levels of cyclin B1 protein and mRNA in the mimic group were significantly lower than those in the control group and the NC group (P<0.01), and the level of mitochondrial-associated protein 2 in the mimic group was significantly higher than that in the control group and the NC group (P<0.01). Conclusions: MiR-150 may inhibit the proliferation, migration, invasion and apoptosis of hepatoma carcinoma cell by regulating cyclin B1 or up-regulating mitochondrial-associated protein 2 levels.

子宫内膜样腺癌组织NuSAP1、MFN2表达与临床病理特征和预后的关系

目的探讨子宫内膜样腺癌(EA)组织核仁纺锤体相关蛋白1(NuSAP1)、线粒体融合蛋白2(MFN2)表达与临床病理特征和预后的关系。方法选取2019年3月至2020年10月南阳市第一人民医院收治的121例EA患者作为研究对象,应用免疫组织化学染色法检测患者癌组织及其对应癌旁组织NuSAP1、MFN2阳性表达率,分析癌组织NuSAP1、MFN2阳性表达率与患者临床病理特征的关系。出院后随访3年,完成随访112例,应用Kaplan-Meier生存曲线分析NuSAP1、MFN2阳性表达组和阴性表达组的预后差异,应用多因素COX回归分析EA患者预后的影响因素。结果EA癌组织NuSAP1阳性表达率为72.37%,明显高于癌旁组织的35.54%,MFN2阳性表达率为38.02%,明显低于癌旁组织的80.17%,差异均有统计学意义(P<0.05);国际妇产科联盟(FIGO)临床分期Ⅱ~Ⅲ期、中低分化、有淋巴结转移、深肌层浸润癌组织中NuSAP1阳性表达率分别为88.68%、83.54%、96.15%、90.63%,明显高于FIGO临床分期Ⅰ期的60.29%、高分化的57.14%、无淋巴结转移的55.79%、浅肌层浸润癌组织的66.29%,差异均有统计学意义(P<0.05);FIGO临床分期Ⅱ~Ⅲ期、中低分化、有淋巴结转移、深肌层浸润癌组织中MFN2阳性表达率分别为18.87%、30.38%、7.69%、15.63%,明显低于FIGO临床分期Ⅰ期的52.94%、高分化的52.38%、无淋巴结转移的46.32%、浅肌层浸润癌组织的46.07%,差异均有统计学意义(P<0.05);Kaplan-Meier法分析结果显示,NuSAP1阴性表达组和MFN2阳性表达组患者的3年生存率分别为90.00%和87.80%,明显高于NuSAP1阳性表达组的69.51%和MFN2阴性表达组的67.61%,差异均有统计学意义(P<0.05)。结论EA患者组织中NuSAP1阳性表达率升高,MFN2阳性表达率降低,NuSAP1、MFN2表达水平与患者肿瘤分化、FIGO临床分期、淋巴结转移及深肌层浸润有关,且是患者死亡的危险因素,提示NuSAP1、MFN2可能参与了EA患者的疾病进展。

胸腺素α_1 基因的克隆表达及其生物活性

胸腺素α1(thymosinalpha 1 ,Tα1)作为一种免疫增强剂 ,临床用途广泛 .为大量制备Tα1,按大肠杆菌惯用密码子合成Tα1基因 ,克隆于质粒pUC1 9的EcoRⅠ和PstⅠ位点 .经测序证明序列正确后 ,串联为 4串体 (Tα1④ ) ,经再次测序确认后克隆入pThioHisA的EcoRⅠ和PstⅠ位点 .转化大肠杆菌T0P1 0 ,酶切鉴定正确后 ,经 1mmol LIPTG诱导 4h ,获得硫氧还蛋白与Tα1④的融合表达 ,用离子交换层析纯化融合蛋白 .溴化氰裂解融合蛋白 ,释放出Tα1单体 ,经离子交换色谱纯化出Tα1.采用3 H TdR参入法进行生物活性测定 ,证实融合蛋白和Tα1均具有刺激小鼠脾淋巴细胞分裂增殖的能力 .

人胸腺素α1基因在毕赤酵母中的分泌表达

根据质粒pPIC9K中信号肽基因和质粒pPIC3 5K/hTα1-RP ,构建表达质粒pPIC9K S -hTα1-RP ,通过电激法转化到毕赤酵母GS115菌株中。甲醇诱导表达融合蛋白 ,SDS -PAGE和Westernblot结果证明 。

重组胸腺素α_1的分离纯化和活性测定

目的 利用融合表达载体 p Thio His A的重组质粒p Thio His A- Tα1 4,转化大肠杆菌 TOP10得到的工程菌 ,来分离纯化表达的胸腺素 α1 (thym osin alpha1,Tα1 ) .方法 将高效表达融合蛋白的工程菌用细胞破碎器裂解 ,经 80℃热处理 ,离心上清采用 Q- Sepharose FF阴离子交换色谱纯化融合蛋白 .融合蛋白经 CNBr裂解后用常压离子交换色谱纯化Tα1 单体 .应用 SDS- PAGE,2 L - Tricine- SDS- PAGE和 HPL C进行鉴定 .结果 SDS- PAGE分析表明菌体表达的融合蛋白占菌体总蛋白的 40 0 g· kg- 1 .经 2 L - Tricine- SDS- PAGE分析证实 ,融合蛋白可裂解出 Tα1 单体 ,裂解物经简单的离子色谱可以纯化出 Tα1 单体 ,HPL C鉴定纯化出的 Tα1 纯度可达95 0 g· kg- 1以上 .利用 3H- Td R进行的生物活性测定表明 ,在致有丝分裂原 Con A存在的条件下 ,融合蛋白和 Tα1 单体均具有刺激小鼠脾淋巴细胞分裂增殖的能力 ,与化学合成的Tα1 相比具有相似的生物活性 .结论 该方法是分离纯化Tα1 简便易行 ,经济有效的方法 ;同时也为 Tα1

重组胸腺素α1的纯化及活性

将胸腺素α1基因 4串体克隆于 pThioHisA融合表达载体 (pThioHisA Tα1④ ) ,转化大肠杆菌TOP10。在IPTG诱导下 ,融合蛋白得到了高效表达。SDS PAGE分析确定诱导表达的融合蛋白占菌体总蛋白的 40 % ,且表达的融合蛋白主要以可溶形式存在。把用离子交换层析纯化出的目的蛋白进行CNBr化学裂解 ,经简单的离子交换层析可纯化出胸腺素α1单体 ,HPLC鉴定胸腺素α1的纯度达 98%。利用3 H TdR进行生物活性测定 ,证实融合蛋白和胸腺素α1单体均具有在致有丝分裂原ConA存在的条件下 ,刺激小鼠脾淋巴细胞分裂增殖的能力 ,与化学合成的胸腺素α1相比具有相似的生物活性。

重组胸腺素α_1的克隆、表达与纯化

目的 利用基因工程方法表达胸腺素α1 (thymosinalpha1,Tα1 )的串联体并进行纯化、鉴定 .方法 将 Tα1 的基因拆分为 4个片段进行合成 ,退火后经 PCR获得串联体基因 ,测序正确后克隆在硫氧还蛋白 (thioredoxin)融合蛋白表达载体 p Thio His A中 ,转化大肠杆菌 TOP10菌株 ,IPTG诱导表达 ,表达的融合蛋白经过 80℃热处理及阴离子交换柱Q- Sepharose Fast Flow进行纯化 ,Western- blot进行鉴定 .结果 获得了纯化的 Thioredoxin- Tα1 3,分子质量约为 31ku.结论 用基因串联思路表达小分子多肽是一种可行的方法 ,Tα1

人胸腺素α1在大肠杆菌中的融合表达

利用基因工程表达的方法 ,在大肠杆菌中通过与GST蛋白融合的方式高效表达了胸腺素α1前体基因 ,随后经亲和层析和SP强阳离子树脂纯化相结合的方式 ,得到了胸腺素前体肽段 31肽和N 端未经乙酰化修饰的 2 8肽。融合蛋白表达量达到菌体总蛋白的 35 %～ 40 % ,样品肽的产量也达到了约 2 0 0mg L(肽 发酵液 )的产量。经质谱测定 ,分子量分别为 336 6和 30 6 6。BalB C小鼠脾脏淋巴细胞体外测活表明 ,所构建的GST Tα1融合蛋白和纯化后的产物对于淋巴细胞具有比较明显的增殖作用 ,其中N 端未经乙酰化的 2 8肽产物与 31肽产物活性相近 。

重组人胰高血糖素样肽-1的表达、纯化及其生物学活性

为获得重组人胰高血糖素样肽 1[recombinanthumanglucagon likepeptide 1(7～ 37) ,rhGLP 1]并研究其生物学活性 ,采用亚磷酸二酯法合成hGLP 1cDNA的 6个寡核苷酸片段 ,拼接成完整的hGLP 1cDNA ,构建重组质粒pGEX hGLP 1,转化大肠杆菌BL2 1(DE3)获得表达菌株 .高密度发酵培养的菌体超声破碎后 ,裂解液用Glutathione Sepharose 4B亲和层析纯化得到GST融合蛋白 .经CNBr裂解、QAE SepharoseFF柱层析和脱盐 ,得到纯度大于 90 %的rhGLP 1,质谱测定分子量结果与理论值一致 .生物学活性分析表明 ,rhGLP 1具有明显的降血糖活性 .

屋尘螨变应原Der p 1基因原核表达产物的纯化及特性鉴定

目的建立屋尘螨主要变应原Derp1蛋白原核表达产物的纯化方法,获得理想的表达产物并鉴定其免疫原性。方法大量诱导表达含pET24a-Derp1质粒的BL21工程菌,表达产物以重组蛋白包涵体的形式存在,包涵体经洗涤与溶解后,使用结合6组氨酸的镍柱进行亲和层析纯化蛋白质,用稀释复性方法进行重组蛋白的复性,再用屋尘螨过敏性哮喘患者阳性血清经Dot-ELISA方法分析Derp1纯化蛋白的抗原活性。结果分步洗涤可有效去除重组蛋白包涵体沉淀中混杂的多数杂蛋白成分,亲和层析分离可获得高纯度重组变应原Derp1蛋白。Dot-ELISA法检测结果表明经复性并纯化的Derp1蛋白呈强阳性反应,最佳血清稀释度为1∶64,而重组蛋白与正常人血清呈阴性反应。结论纯化后的融合蛋白Derp1具有较高的纯度及较强的免疫活性,可望作为有效的屋尘螨变应原诊断试剂和疫苗的候选分子。