Clinical application of SARS-CoV-2 antibody detection and monoclonal antibody therapies against COVID-19

The purpose of this study was to investigate the clinical application of severe acute respiratory distress syndrome coronavirus-2(SARS-CoV-2)specific antibody detection and anti-SARS-CoV-2 specific monoclonal antibodies(mAbs)in the treatment of coronavirus infectious disease 2019(COVID-19).The dynamic changes of SARS-CoV-2 specific antibodies during COVID-19 were studied.Immunoglobulin M(IgM)appeared earlier and lasted for a short time,while immunoglobulin G(IgG)appeared later and lasted longer.IgM tests can be used for early diagnosis of COVID-19,and IgG tests can be used for late diagnosis of COVID-19 and identification of asymptomatic infected persons.The combination of antibody testing and nucleic acid testing,which complement each other,can improve the diagnosis rate of COVID-19.Monoclonal anti-SARS-CoV-2 specific antibodies can be used to treat hospitalized severe and critically ill patients and non-hospitalized mild to moderate COVID-19 patients.COVID-19 convalescent plasma,highly concentrated immunoglobulin,and anti-SARS-CoV-2 specific mAbs are examples of anti-SARS-CoV-2 antibody products.Due to the continuous emergence of mutated strains of the novel coronavirus,especially omicron,its immune escape ability and infectivity are enhanced,making the effects of authorized products reduced or invalid.Therefore,the optimal application of anti-SARS-CoV-2 antibody products(especially anti-SARS-CoV-2 specific mAbs)is more effective in the treatment of COVID-19 and more conducive to patient recovery.

Therapeutic Implications of Monoclonal Antibody

Background: The coronavirus disease 2019 (COVID-19) pandemic is a distinct public health issue that calls for the quick development of novel treatments and viral detection. Due to their high specificity and reliability, monoclonal antibodies (mAbs) have emerged as useful diagnostic and therapeutic tools for a variety of diseases. As a result, several scientists have jumped right into developing Ab-based assays for the identification of SARS-CoV-2 and Ab drugs for use as COVID-19 therapy agents. Since the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein is essential for viral infection and has a known precise structure, it has become a key target for the creation of therapeutic antibodies. The use of Ab cocktails is anticipated to be a key component of an efficient COVID-19 treatment plan since SARS-CoV-2 is an RNA virus with a high mutation rate, particularly when subjected to the selection pressure of aggressively applied preventive vaccinations and neutralizing Abs. Furthermore, SARS-CoV-2 infection could provoke an overzealous immune response, leading to a cytokine storm that accelerates the onset of a severe disease. Abs to counteract cytokine storms are also actively being researched as COVID-19 therapies. Abs are now used in SARS-CoV-2 detection assays, including immunoglobulin and antigen tests, in addition to their use as medicines. In order to stop the spread of COVID-19, such Ab-based detection tests are essential surveillance tools. In this article, we’ll go over several important ideas related to mAb-based COVID-19 pandemic detection tests and treatments. Objective: To understand the role of hybridoma technology in therapeutic implications. 1) To study the basic concepts and options in hybridoma technology;2) To study the applications of hybridoma technology;3) To explore how hybridoma technology is applied in diagnostic histopathology. Method: For this method generally there is use of mouse or mammals are transfect with the Ags to find out the formation of antibody afterwards isolate the antibody which has been formed after injecting the antigens for a number of weeks. Following are the steps for mAbs: Step 1: In this step immunization of mouse is done;Step 2: Spleen is used for the isolation of B cells;Step 3: Cultivation of cancerous cells;Step 4: Merging of B cells with Myeloma cells;Step 5: This step cell lines are separated;Step 6: in the next step screening the suitable cell lines;Step 7: observation of multiplication in vitro as well as in vivo;Step 8: Harvesting. Discussion: Now a day there are many diseases which has been cured easily at the mean time it’s very difficult to diagnose and get the treatment. Due to advancement of monoclonal antibodies are used in the diagnosis and treatments such as COVID-19, SARS and SARS COV-2. Therefore important part of the monoclonal antibodies are its used in the diagnosis as well as in the treatment tools.

Tumoricidal activation of murine resident peritoneal macrophages on pancreatic carcinoma by interleukin-2 and monoclonal antibodies

INTRODUCTIONMacrophages play an important role in tumor lysisand growth inhibition.They can be activated to atumoricidal state by a variety of agents such asIFNr,TNFα or IL2.The killing machanisms ofactivated macrophages have been extensivelyinvestigated.Recently,it has been proved thatantibody dependent cellular cytotoxicity (ADCC) isone of the potent arms to lyse tumor cells

Synthesis and evaluation of monoclonal antibody against Plasmodium falciparum merozoite surface antigen 2

Objective:To assess the quality of expressed MSP-2 and also to confirm the immune response against different domains of these proteins.Methods:Mice were immunized with a schizont extract to stimulate the immune system to make antibodies against different antigens of the late stage parasite including production of antibodies against different domains of Plasmodium falciparum(P.falciparum)MSP-2.B lymphocytes of immunized mice were extracted from the spleen and the fusion was performed using NS-1 myeloma cells and the hybridoma cells were assayed by ELISA either with a schizont extract or different domains of MSP-2 and/or by IFAT with whole schizont preparation.Fusion of NS-1 and spleen cells was performed.The positive hybrids were cloned and ELISA was applied against different dilutions.The positive clones were transferred to a small tissue culture flask and after developing they were assayed against schizont extract and the different MSP-2 domains.The positive clones were expanded to large(75 cm^2)flask and cultured under the same conditions,checking them using both ELISA and IFAT and the positive cells were frozen as soon as possible.Results:A total number of 7 fusions including 26 plates(2496 wells)were performed,of which 1336 hybrids were produced and the overall efficiency(1336/24%×100)was about 53%.ELISA was performed to detect the positive hybrids against crude schizont extract by which the highest frequency to crude schizont extract was found for the supernatant of the hybrids produced in fusion number 3(66 out of 315 hybrids).The supernatant of both B5 and Ft hybridoma cells were more positive against domain 2 of the MSP-2 recombinant protein in Western blotting test.Western blotting results also showed that different domains of the MSP-2 recombinant protein and also the MSP-2 of the P.falciparum parasite were recognized by some of the positive clones and also immune sera.Conclusions:Bringing together all the results of this study it has been confirmed that some clones have recognized both schizont extract and different domains of the MSP-2 recombinant protein and therefore confirming the quality of the MSP-2 domains.

Effect of bovine pellucid zone 3 monoclonal antibodies on B cell lymphoma 2 expressions of granulosa cell and mice (Mus musculus) follicle diameter

Objective:To evaluate the effects of pellucid zone 3 monoclonal antibodies against B-cell lymphoma 2 (BCL-2) expression and mice follicle diameter at various time periods.Methods:The animal model of this study was 36 Balb/c mice (Mus musculus). A true experimental design was used with a post-test only control group approach. BCL-2 expression was observed using immunohistochemistry, while the follicle diameter was observed by haematoxylin-eosin staining. The data was analyzed using nested ANOVA to compare the results of the mean expression of BCL-2 on the 5th and 20th day of observation in the pre-antral and antral follicle between the control and treatment groups.Results:No significant differences were found in BCL-2 gene expression. There were also no significant differences in BCL-2 expression on the 10th day of pre-antral follicle analysis. Moreover, there were no significant differences between the mean follicle diameter on the 5th, 10th, and 20th day of pre-antral and antral follicle development between the control and treatment groups. The addition of bovine pellucid zone 3 (bZP3) monoclonal antibodies on the 5th and 20th day of observation did not decrease the expression of BCL-2 gene in the pre-antral and antral follicle of mice. Administering bZP3 monoclonal antibodies on the 10th day of observation did not affect BCL-2 expression in the pre-antral follicle but did decrease BCL-2 expression in the antral follicle. Supplying bZP3 monoclonal antibodies on the 5th, 10th and 20th day did not affect the diameter of pre-antral and antral follicles of the mice.Conclusion: The monoclonal antibodies bovine zona pelusida 3 has the potential to be developed as a safe immunocontraception preparation.

靶向HER2胞外结构域Ⅳ的单克隆抗体在乳腺癌中的应用进展

人表皮生长因子受体2(HER2)阳性乳腺癌侵袭性强且易转移,抗HER2靶向药物的应用能显著改善HER2阳性乳腺癌患者的预后。在已上市的HER2靶向药物中,靶向HER2胞外结构域Ⅳ的大分子单克隆抗体是治疗HER2阳性乳腺癌的基础靶向药物,主要包括曲妥珠单抗、伊尼妥单抗和马吉妥昔单抗。曲妥珠单抗用于乳腺癌全线治疗,循证医学证据充分,实践经验充足且安全性可控;伊尼妥单抗与曲妥珠单抗在HER2阳性转移性乳腺癌和新辅助/辅助治疗中疗效相似,且安全性可控;马吉妥昔单抗聚焦于携带CD16A-158F等位基因的患者,是晚期乳腺癌后线治疗的选择。临床上需根据患者具体病情选择最适合的药物。

A human monoclonal antibody neutralizes SARS-CoV-2 Omicron variants bytargeting the upstream region of spike protein HR2 motif

The continuous emergence of new severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants meansthere is a need to explore additional strategies to develop broad-spectrum vaccines or therapeutics for individuals remaining at risk of coronavirus disease 2019(COVID-19).Neutralizing monoclonal antibody(mAb)that binds to theconserved S2 subunit of the SARS-CoV-2 spike(S)protein alone,or in combination with mAb that binds to the receptor-binding domain(RBD)of S protein,might be effective in eliciting protection from infection by a variety of SARS-CoV2 variants.Using high-throughput single-cell immunoglobulin sequencing of B cells from COVID-19-convalescent donors,we identified a high-affinity S2-specific mAb-39,that could inhibit original SARS-CoV-2 strain,Omicron BA.1,BA.2.86,BA.4,BA.5,and EG.5.1 S protein-mediated membrane fusion,leading to the neutralization of these pseudoviralinfections.Moreover,mAb-39 could also improve the neutralizing activity of anti-RBD antibody against the highlyneutralization-resistant Omicron variants.Molecular docking and point mutation analyses revealed that mAb-39 recognized epitopes within the conserved upstream region of the heptad repeat 2(HR2)motif of the S2 subunit.Collectively,these findings demonstrate that targeting the conserved upstream region of the HR2 motif(e.g.,using mAbs)provides anovel strategy for preventing the infection of SARS-CoV-2 and its variants.

抗HER2单抗注射液(皮下注射)的质量控制

目的 研究并建立针对抗HER2单抗注射液(皮下注射)的关键质量属性质控方法。方法 分别采用胰蛋白酶或Lys-C酶切结合反相高效液相色谱法(reversed-phase high performance liquid chromatography, RP-HPLC)的肽图分析法进行抗HER2单抗的特异性鉴别。采用还原/非还原十二烷基硫酸钠毛细管电泳(capillary electrophoresis-sodium dodecyl sulfonate, CE-SDS)和分子排阻色谱(size-exclusion chromatography, SEC)法进行纯度控制。采用阳离子交换色谱(ion-exchange chromatography, IEC)法进行电荷异质性分析。采用亲水相互作用液相色谱(hydrophilic interaction liquid chromatography, HILIC)法进行寡糖图谱分析。采用酶活力测定法分析透明质酸酶含量。采用BT474细胞增殖抑制法测定生物学活性。采用紫外分光光度法测定蛋白含量。结果 两种肽图检测法均获得特征图谱,对抗HER2单抗发挥很好的特异性鉴别作用。还原CE-SDS的重链和轻链峰面积之和百分比为(98.63±0.14)%,非还原CE-SDS主峰面积百分比为(98.20±0.11)%,前峰面积百分比总和为(1.47±0.04)%。SEC测得的单体峰面积百分比为(99.82±0.05)%。IEC测定的主要活性成分(峰3*+峰3)以及产品相关杂质(峰4)的峰面积百分比分别为(75.01±0.04)%和(6.72±0.03)%。寡糖图谱分析aFuc、G2和Man5的面积百分比分别为(9.20±0.01)%,(6.33±0.02)%和(1.92±0.01)%。透明质酸酶含量为(2 021.02±238.41)U/ml。供试品相对于参比品的生物学活性为(95.87±6.10)%,蛋白含量为(115.60±0.45)mg/ml。结论 针对抗HER2单抗注射液(皮下注射)关键质量属性的质控方法的建立可以有效确保该类产品的安全性和有效性。

ANGPT2单克隆抗体对AML小鼠肿瘤组织血管增生和下游信号蛋白表达的影响

目的 探讨ANGPT2单克隆抗体对急性髓系白血病(AML)小鼠肿瘤组织血管增生、下游信号蛋白表达的影响。方法 建立AML小鼠模型20只,对照组与实验组各10只,采用免疫组织化学方法检测微血管密度及VEGF表达情况,采用Western blot检测下游信号通路蛋白TIE2、SHP2和PI3K的表达水平。结果 ANGPT2单克隆抗体治疗后,AML小鼠肿瘤组织微血管密度及VEGF表达水平显著下降79.29%(P<0.01),下游信号通路蛋白SHP2蛋白表达水平上升59.43%,PI3K蛋白表达水平下降20.37%(P<0.01)。结论 ANGPT2单克隆抗体显著抑制AML小鼠肿瘤组织血管增生。

PD-L2在头颈部鳞状细胞癌免疫治疗预后评估中的意义

背景与目的:程序性死亡[蛋白]-1(programmed death-1,PD-1)单抗免疫治疗在头颈部鳞状细胞癌(head and neck squamous cell carcinoma,HNSCC)中的作用愈发重要,然而目前具有响应率低、缺乏预测性生物标志物的问题。本研究旨在确定程序性死亡[蛋白]配体-2(programmed death ligand-2,PD-L2)能否作为预测HNSCC中PD-1单抗免疫治疗获益情况的生物标志物。方法:收集50例接受PD-1单克隆抗体免疫治疗的中晚期HNSCC的组织标本及临床数据,采用免疫组织化学染色法分析程序性死亡[蛋白]配体-1(programmed death ligand-1,PD-L1)、PD-L2表达量,采用SPSS 26.0软件根据基本临床特征、PD-L1与PD-L2表达量分组统计并进行Kaplan-Meier生存分析,采用GraphPad Prism软件绘制生存曲线。结果:PD-L2在HNSCC患者中阳性表达率较高,有超过80%的患者肿瘤组织可检出PD-L2表达;PD-L2的表达量显著影响免疫治疗结局,PD-L2高表达的患者平均生存期为18.8(16.0~21.7)个月,而PD-L2低表达的患者平均生存期为11.0(9.1~12.8)个月,差异有统计学意义(P<0.05)。结论:PD-L2可作为评估HNSCC中PD-1单克隆抗体免疫治疗获益的生物标志物。

鸭腺病毒3型Fiber-2蛋白单克隆抗体的制备及初步应用

为进一步研究鸭腺病毒3型(DAdV-3)Fiber-2蛋白,研究通过PCR扩增fiber-2基因,构建p ET32a-DAdV3-fiber2原核质粒,表达并纯化蛋白,以纯化的蛋白为免疫原,免疫6周龄雌性BALB/c小鼠制备抗Fiber-2单克隆抗体杂交瘤细胞,采用间接免疫荧光试验和免疫印迹试验进行鉴定,并用于DAdV-3 Fiber-2杆状病毒表达产物的鉴定。结果显示:原核表达获得1.77 mg/mL Fiber-2蛋白,筛选获得2株阳性单克隆细胞株2E10E4和4F7F10,两株单克隆抗体均为IgG 1型,轻链类型为κ;DAdV-3感染的LMH细胞中存在特异性荧光,免疫印迹试验确认在约59 ku处出现特异性条带;采用制备的单克隆抗体确认了表达Fiber-2蛋白的重组杆状病毒。研究获得了针对DAdV-3 Fiber-2蛋白的单克隆抗体,为深入探究Fiber-2在DAdV-3感染机制中的作用以及为建立DAdV-3抗原免疫测定技术奠定了基础。

针对SARS-CoV-2核衣壳蛋白的单克隆抗体的制备和鉴定

目的研制SARS-CoV-2的N蛋白单克隆抗体,并对其特异性识别真核表达N蛋白等特性进行鉴定,为下一步应用奠定材料基础。方法利用大肠杆菌表达并纯化SARS-CoV-2重组N蛋白,制备并筛选分泌N蛋白特异性单克隆抗体的阳性B细胞杂交瘤,制备腹水后利用间接ELISA法测定单抗的效价、亚型和亲和力;通过Western blot、间接免疫荧光试验分析其与原核、真核表达SARS-CoV-2重组N蛋白的特异性结合能力;通过间接ELISA法评价其在不同冠状病毒N蛋白检测中的应用潜力。结果成功地表达和纯化SARS-CoV-2重组N蛋白,筛选获得1株特异性识别重组N蛋白的单克隆抗体并命名为11F4,其亚型为IgG1,腹水效价为2.0×10^(7)以上,亲和力为4.44×10^(8)M^(-1);Western Blot分析表明其能与SARS-CoV-2重组N蛋白特异性反应,间接免疫荧光试验显示其能特异性识别HEK-293T细胞表达的SARS-CoV-2 N蛋白,表明该蛋白免疫反应性良好;间接ELISA法结果表明其可特异性识别真核细胞表达的SARS-CoV-2 N蛋白,而与MERS-CoV和HCoV-229E的N蛋白无交叉反应。结论成功获得可特异性识别细胞表达及体外制备的SARS-CoV-2 N蛋白的单克隆抗体,具备特异性检测SARS-CoV-2的潜能,为下一步研究提供了重要生物材料。

兔出血症病毒2型SC株VP60蛋白特异性单克隆抗体的制备及鉴定

为了获得我国兔出血症病毒2型(RHDV2)SC株特异性单克隆抗体,研究以纯化RHDV2作为抗原免疫BALB/c小鼠,4次免疫后取脾细胞与SP2/0细胞融合,经间接ELISA方法筛选,获得一株能够稳定分泌RHDV2 VP60蛋白特异性单克隆抗体的杂交瘤细胞,命名为6B3。经Western blot和间接免疫荧光试验验证,该单克隆抗体可识别RHDV2,不与RHDV1反应,具有良好的毒株特异性。亚型鉴定结果为IgG3,轻链为Kappa型,腹水ELISA效价为1∶80 000。本研究得到的针对RHDV2的特异性单抗,将对我国兔出血症的诊断及流行病学调查提供有效制剂。

GD-2单抗治疗高危/难治神经母细胞瘤儿童的临床诊治体会

目的:探讨GD-2单抗免疫治疗高危及复发难治神经母细胞瘤患儿的临床反应及治疗效果。方法:回顾性分析22例接受GD-2单抗免疫治疗的儿童神经母细胞瘤患者,分析GD-2单抗免疫治疗的耐受性、不良反应及短期治疗效果评估。结果:22例患者在接受GD-2单抗免疫治疗过程的不同治疗周期中均出现发热症状:其中第1个治疗周期出现发热为100%,平均热峰39.0℃,平均持续时间6.75 d;5例(22%)患者出现感染,8例(36%)患者出现疼痛反应,11例(50%)患者发生腹泻,2例(9%)患者发生过敏反应,2例(9%)患者发生轻度毛细血管渗漏综合征(CLS);其中5个患者完成5个治疗周期,经评估1例病情明显好转,2例病情稳定无进展,1例病灶较前缩小,1例复发。结论:GD-2单抗免疫治疗对儿童神经母细胞瘤具有良好的安全性和耐受性,其远期疗效需进一步随访评估。

Hybridoma-derived neutralizing monoclonal antibodies against Beta and Delta variants of SARS-CoV-2 in vivo

Neutralizing monoclonal antibodies(mAb)are a major therapeutic strategy for the treatment of severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection.The continuous emergence of new SARS-CoV-2 variants worldwide has increased the urgency for the development of new mAbs.In this study,we immunized mice with the receptor-binding domain(RBD)of the SARS-CoV-2 prototypic strain(WIV04)and screened 35 RBDspecific mAbs using hybridoma technology.Results of the plaque reduction neutralization test showed that 25 of the mAbs neutralized authentic WIV04 strain infection.The 25 mAbs were divided into three categories based on the competitive enzyme-linked immunosorbent assay results.A representative mAb was selected from each category(RD4,RD10,and RD14)to determine the binding kinetics and median inhibitory concentration(IC_(50))of WIV04 and two variants of concern(VOC):B.1.351(Beta)and B.1.617.2(Delta).RD4 neutralized the B.1.617.2 variant with an IC50 of 2.67 ng/mL;however,it completely lost neutralizing activity against the B.1.351 variant.RD10 neutralized both variants with an IC50 exceeding 100 ng/mL;whereas RD14 neutralized two variants with a higher IC50(>1 mg/mL).Animal experiments were performed to evaluate the protective effects of RD4 and RD10 against various VOC infections.RD4 could protect Adv-hACE2 transduced mice from B.1.617.2 infection at an antibody concentration of 25 mg/kg,while RD10 could protect mice from B.1.351 infection at an antibody concentration of 75 mg/kg.These results highlight the potential for future modifications of the mAbs for practical use.

Neutralizing Antibodies Bloek COVID-19 Virus Binding to Its Reeeptor ACE2

As revealed in a research published lately in Science,two human-origin monoclonal antibodies identified and reproduced by Chinese scientists were able to protect mice from COVID-19.These virus-neutralizing antibodies,acting to block the virus binding to its victim cells,were harvested from the blood of a convedescent donor once infected with COVID-19.

晚期胆道癌抗HER-2治疗临床研究进展

胆道癌(BTC)是起源于胆管上皮的一组恶性肿瘤,异质性高,治疗棘手,预后差,生存期短。晚期BTC的治疗既往主要依赖于化疗,新近免疫联合化疗一线治疗已获得成功;同时,随着对胆道肿瘤的基因组和蛋白组特征认识的不断加深,业已明确其分子分型,且发现了若干分子生物标志物,因此靶向药物在二线治疗BTC的研究如火如荼,正在改变BTC的治疗格局和结局。抗人表皮生长因子受体-2(HER-2)治疗,已在乳腺癌和胃癌等多种肿瘤的治疗中显著改善患者预后,现正在积极探索用于治疗BTC,初步显示了可期的美好前景。本文简要综述了抗HER-2治疗BTC的临床研究进展,提出需要进一步开展基于分子生物标志物HER-2驱动的随机对照、大规模的多中心Ⅲ期研究。

猪圆环病毒2型血清中和抗体阻断ELISA检测方法的建立及应用

利用PCV2-Cap蛋白中和性单克隆抗体建立了一种检测猪血清中PCV2中和抗体的阻断ELISA方法。用该方法与免疫过氧化物酶单层细胞试验对353份试验猪血清样品进行平行检测,结果两种方法的符合率为96.0%;该方法的敏感性为97.9%,特异性为92.4%,且与其他几种猪病毒参考阳性血清无交叉反应。该阻断ELISA与血清中和试验的检测结果呈显著正相关(r=0.997 0),其敏感性还优于血清中和试验。用阻断ELISA对PCV2灭活疫苗免疫与攻毒试验猪血清样品进行检测,结果显示,疫苗接种后第2周就能检测到PCV2中和抗体,4周后阳转率达100%。另外,用该方法对东北三省不同地区送检的703份血清样品进行检测,结果阳性检出率为73.0%。表明,东北三省猪场中的PCV2感染率较高,危害严重。

抗鸭IL-2单克隆抗体的制备与鉴定

用纯化的重组鸭IL-2蛋白免疫BALB/c小鼠,取其脾细胞与SP2/0骨髓瘤细胞融合,对杂交瘤细胞进行筛选,阳性孔经三次有限稀释法克隆,成功获得5株能稳定传代并分泌抗鸭IL-2单克隆抗体(mAb)的杂交瘤细胞,分别命名为:1H4、2B3、4G12、5F6、5H6,其中一株对鸡IL-2具有交叉反应性.各单克隆抗体腹水间接ELISA效价在1∶32000～1∶512000之间,抗体类型除mAb5H6为IgG2a亚类外,其余4株mAb均为IgG1亚类,5株mAb的轻链都为κ链.经Western-blot分析表明,所获得的5株抗鸭IL-2单克隆抗体与鸭IL-2具有反应性,推测它们是针对序列决定簇的.

重组鸡白细胞介素2的诱导表达与生物学活性测定

将去除信号肽的鸡IL-2基因编码框克隆到原核表达载体pBAD/HisB,实现了重组鸡IL-2(rchIL-2)蛋白在大肠杆菌中的高效表达。SDS-PAGE分析显示,表达蛋白的分子量约为18kD。用rchIL-2为抗原制备了单克隆抗体和多克隆抗体,建立了检测rchIL-2含量的抗原捕获ELISA,探讨了天然chIL-2蛋白的体外表达动力学。非变性条件下纯化的rchIL-2(0.4ng)对ConA活化的鸡T淋巴细胞具有明显的增殖活性,而对鸭及鹅的T淋巴细胞无增殖活性。抗chIL-2多克隆抗体可完全中和rchIL-2和天然chIL-2蛋白的生物学活性,而单克隆抗体无中和rchIL-2和天然chIL-2蛋白生物学活性的功能。这些研究结果证实,大肠杆菌表达的rchIL-2及其多克隆抗体拥有生物学功能,而获得的单克隆抗体不具有chIL-2的中和特性。