Phase I study of chimeric anti-CD20 monoclonal antibody in Chinese patients with CD20-positive non-Hodgkin＇s lymphoma

Objective： This study was designed to determine the safety, pharmacokinetics and biologic effects of a humanmouse chimeric anti-CD20 monoclonal antibody （SCT400） in Chinese padents with CD20-positive B-cell non- Hodgkin＇s lymphoma （CD20 B-cell NHL）. SCT400 has an identical amino acid sequence as rituximab, with the exception of one amino acid in the CH1 domain of the heavy chain, which is common in Asians. Methods： Fifteen patients with CD20＋ B-cell NHL received dose-escalating SCT400 infusions （250 mg/m2： n=3; 375 mg/m2： n=9; 500 mg/m2： n=3） once weekly for 4 consecutive weeks with a 24-week follow-up period. The data of all patients were collected for pharmacoklnetics and pharmacodynamics analyses. Results： No dose-limiting toxicities were observed. Most drug-related adverse events were grade 1 or 2. Two patients had grade 3 or 4 ncutropenia. Under premedication, the drug-related infusion reaction was mild. A rapid, profound and durable depletion of circulating B cells was observed in all dose groups without significant effects on T cell count, natural killer （NK） cell count or immunoglobulin levels. No patient developed anti- SCT400 antibodies during the course of the study. SCT400 serum half-life （Tin）, maximum concentration （Cmax and area under the curve （AUC） generally increased between the first and fourth infusions （P〈0.05）. At the 375 mg/m2 dose, the T1/2 was 122.5±46.7 h vs. 197.0,75.0 11, respectively, and the Cmax was 200.6±20.2 pg/mL vs. 339.1±71.0 ng/mL, respectively. From 250 mg/m2 to 500 mg/m2, the Cmax and AUC increased significantly in a dose-dependent manner （P〈0.05）. Patients with a high tumor burden had markedly lower serum SCT400 concenmations compared with those without or with a low tumor burden. Of the 9 assessable patients, 1 achieved complete response and 2 achieved partial responses. Conclusions; SCT400 is well-tolerated and has encouraging preliminary efficacy in Chinese patients with CD20＋ B-cell NHL.

Time-Programmed Delivery of Sorafenib and Anti-CD47 Antibody via a Double-Layer-Gel Matrix for Postsurgical Treatment of Breast Cancer

The highly immunosuppressive microenvironment after surgery has a crucial impact on the recurrence and metastasis in breast cancer patients.Programmable delivery of immunotherapy-involving combinations through a single drug delivery system is highly promising,yet greatly challenging,to reverse postoperative immunosuppression.Here,an injectable hierarchical gel matrix,composed of dual lipid gel(DLG)layers with different soybean phosphatidylcholine/glycerol dioleate mass ratios,was developed to achieve the time-programmed sequential delivery of combined cancer immunotherapy.The outer layer of the DLG matrix was thermally responsive and loaded with sorafenib-adsorbed graphene oxide(GO)nanoparticles.GO under manually controlled near-infrared irradiation generated mild heat and provoked the release of sorafenib first to reeducate tumor-associated macrophages(TAMs)and promote an immunogenic tumor microenvironment.The inner layer,loaded with anti-CD47 antibody(aCD47),could maintain the gel state for a much longer time,enabling the sustained release of aCD47 afterward to block the CD47-signal regulatory proteinα(SIRPα)pathway for a long-term antitumor effect.In vivo studies on 4T1 tumor-bearing mouse model demonstrated that the DLG-based strategy efficiently prevented tumor recurrence and metastasis by locally reversing the immunosuppression and synergistically blocking the CD47-dependent immune escape,thereby boosting the systemic immune responses.

Veterans health administration hepatitis B testing and treatment with anti-CD20 antibody administration

AIM: To evaluate pretreatment hepatitis B virus (HBV) testing, vaccination, and antiviral treatment rates in Veterans Affairs patients receiving anti-CD20 Ab for quality improvement.METHODS: We performed a retrospective cohort study using a national repository of Veterans Health Administration (VHA) electronic health record data. We identified all patients receiving anti-CD20 Ab treatment (2002-2014). We ascertained patient demographics, laboratory results, HBV vaccination status (from vaccination records), pharmacy data, and vital status. The high risk period for HBV reactivation is during anti-CD20 Ab treatment and 12 mo follow up. Therefore, we analyzed those who were followed to death or for at least 12 mo after completing anti-CD20 Ab. Pretreatment serologic tests were used to categorize chronic HBV (hepatitis B surface antigen positive or HBsAg+), past HBV (HBsAg-, hepatitis B core antibody positive or HBcAb+), resolved HBV (HBsAg-, HBcAb+, hepatitis B surface antibody positive or HBsAb+), likely prior vaccination (isolated HBsAb+), HBV negative (HBsAg-, HBcAb-), or unknown. Acute hepatitis B was defined by the appearance of HBsAg+ in the high risk period in patients who were pretreatment HBV negative. We assessed HBV antiviral treatment and the incidence of hepatitis, liver failure, and death during the high risk period. Cumulative hepatitis, liver failure, and death after anti-CD20 Ab initiation were compared by HBV disease categories and differences compared using the χ2 test. Mean time to hepatitis peak alanine aminotransferase, liver failure, and death relative to anti-CD20 Ab administration and follow-up were also compared by HBV disease group.RESULTS: Among 19304 VHA patients who received anti-CD20 Ab, 10224 (53%) had pretreatment HBsAg testing during the study period, with 49% and 43% tested for HBsAg and HBcAb, respectively within 6 mo pretreatment in 2014. Of those tested, 2% (167/10224) had chronic HBV, 4% (326/7903) past HBV, 5% (427/8110) resolved HBV, 8% (628/8110) likely prior HBV vaccination, and 76% (6022/7903) were HBV negative. In those with chronic HBV infection, ≤ 37% received HBV antiviral treatment during the high risk period while 21% to 23% of those with past or resolved HBV, respectively, received HBV antiviral treatment. During and 12 mo after anti-CD20 Ab, the rate of hepatitis was significantly greater in those HBV positive vs negative (P = 0.001). The mortality rate was 35%-40% in chronic or past hepatitis B and 26%-31% in hepatitis B negative. In those pretreatment HBV negative, 16 (0.3%) developed acute hepatitis B of 4947 tested during anti-CD20Ab treatment and follow-up.CONCLUSION: While HBV testing of Veterans has increased prior to anti-CD20 Ab, few HBV+ patients received HBV antivirals, suggesting electronic health record algorithms may enhance health outcomes.

Expression of Anti-CD4 Human/Murine Chimeric Antibody and Their Killer Tumor Activity

From the mouse hybridoma cell line secreting an anti-CD4 monoclonal antibody (McAb), total RNA was prepared. The VH and VL genes were amplified by RT-PCR with family specific primer pairs. The PCR products were cloned into pGEM-T vectors, then tranfected into JM109. The VH and VL genes were snalyzed by automatic DNA sequencer. According to Kabat classification, the VH and VL genes belong to the mouse ig heavy subgroup Ⅱ(A) and x chain subgroupⅢ, respectively. The VH and VL genes were subcloned into pr1-Expr and Pk Expr respectively, then transfected into XL2-Blue. The VH- Pr1 and VL- pk were trans feeted by electroporation into mouse myeloma cell X63Ag8. 653. The transfectoma cells were selected by G418 screening, and then supernatant of cultured transfectoma were analyzed by ELISA and immunofluorescence techniques.We have acquired transfectoma cells secreting anti-CD4 chimeric antibodies.These chimeric antibodies are able to kill tumor cells specifically in vitro.

Tumor neoangiogenesis detection by confocal laser endomicroscopy and anti-CD105 antibody:Pilot study

AIM: To evaluate neoangiogenesis in patients with colon cancer by two fluorescently labeled antibodies on fresh biopsy samples imaged with confocal laser endomicroscopy(CLE).METHODS: CLE is an imaging technique for gastrointestinal endoscopy providing in vivo microscopy at subcellular resolution.An important question in validating tumor angiogenesis is what proportion of the tumor vascular network is represented by preexisting parent tissue vessels and newly formed vessels.CD105(endoglin) represents a proliferation-associated endothelial cell adhesion molecule.In contrast to panendothelial markers,such as CD31,CD105 is preferentially expressed in activated endothelial cells that participate in neovascularization.Thus,we evaluated CD105 and CD31 expression from samples of ten patients with primary rectal adenocarcinoma,using a dedicated endomicroscopy system.A imaging software was used to obtain the Z projection of the confocal serial images from each biopsy sample previously combined into stacks.Vascular density and vessel diameters were measured within two 50 μm x 475 μm rectangular regions of interest centered in the middle of each image in the horizontal and vertical direction.The results were averaged over all the patients and were expressed as the mean ± SE.RESULTS: The use of an anti-CD105 antibody was found to be suitable for the detection of blood vessels in colon cancer.Whereas anti-CD31 antibodies stained blood vessels in both normal and pathologic colon equally,CD105 expression was observed primarily in malignant lesions,with little or no expression in the vessels of the normal mucosa(244.21 ± 130.7 vessels/mm3 in only four patients).The average diameter of antiCD105 stained vessels was 10.97 ± 0.6 μm in tumor tissue,and the vessel density was 2787.40 ± 134.8 vessels/mm3.When using the anti-CD31 antibody,the average diameter of vessels in the normal colon tissue was 7.67 ± 0.5 μm and the vessel density was 3191.60 ± 387.8 vessels/mm3,while in the tumors we obtained an average diameter of 10.88 ± 0.8 μm and a vessel density of 4707.30 ± 448.85 vessels/mm3.Thus,there were more vessels stained with CD31 than CD105(P < 0.05).The average vessel diameter was similar for both CD31 and CD105 staining.A qualitative comparison between CLE vs immunohistochemistry lead to similar results.CONCLUSION: Specific imaging and quantification of tumor microvessels are feasible in human rectal cancer using CLE examination and CD105 immunostaining of fresh tissue samples.

Inhibitory Effect of Anti-HER-2 Anti-CD3 Bi-specific Antibody on the Growth of Gastric Carcinoma

To evaluate the effect of anti-HER-2 × anti-CD3 bi-specific antibody（BsAb） on the growth of HER-2/neu-expressing human gastric carcinoma in vitro and in vivo, an MTT assay was carried out to test the inhibitive rates of herceptin, anti-CD3 and BsAb antibodies on SGC-7901 gastric carcinoma cells. Immunocytochemistry methods were used to test the HER-2 level of SGC-7901. Nude mice models were employed to test the effect of HER-2 CD3 BsAh combined with effector ceils（ peripheral blood lymphatic cells of healthy human beings） on the growth of tumors in animals. Compared with that of the untreated control group, the tumor cell growth rates in vitro and in vivo will both be significantly inhibited when treated with effector cells combined with anti-CD3 McAb, herceptin or HER2 CD3 BsAb （p 〈0. 05）, and the growth inhibition is the most remarkable in the group treated with HER2 CD3 BsAb combined with effector cells. The growth of tumor xenografts will also be significantly inhibited in the group treated with HER2 CD3 BsAb combined with effector cells when compared with that in the group treated with anti-CD3 McAb or the group treated with herceptin combined with effector cells（p 〈0. 05）. We can conclude that HER-2/neu is possibly a useful target for immunotherapy of gastric carcinoma, and anti-HER2 × anti-CD3 BsAb has evident anti-tumor efficacy both, in vitro and in vivo.

抗SSA抗体阳性干燥综合征患者血清miR-34、miR-500表达变化及其诊断价值

目的观察抗SSA抗体阳性干燥综合征(p SS)患者血清miR-34、miR-500表达变化,并探讨二者在抗SSA抗体阳性p SS诊断中的临床价值。方法收集p SS患者75例(观察组),非p SS患者84例(对照组),miRNA芯片分析两组血清miRNA表达谱改变;并通过实时荧光定量RT-PCR进行验证。随后应用统计学方法分析异常表达miRNA在抗SSA抗体阳性p SS诊断中的价值。结果 miRNA芯片分析发现6个上调和4个下调的miRNA,其中miR-34和miR-500表达在观察组血清中明显升高;实时荧光定量PCR的结果证实miR-34和miR-500在观察组明显上调,与对照组比较,P<0.001。受试者工作曲线分析结果显示,观察组miR-34对p SS诊断的AUC为0.783(95%CI:0.710~0.844,P<0.001);miR-500的AUC为0.774(95%CI:0.701~0.837,P<0.001)。而miR-34联合miR-500在p SS诊断中AUC为0.888(95%CI:0.828~0.932,P<0.001);两者联合诊断p SS的AUC与单一检测比较,P均<0.05。结论 miR-34和miR-500在抗SSA抗体阳性p SS患者血清中表达升高,检测血清miR-34和miR-500有助于抗SSA抗体阳性p SS诊断。

A p34 ^( cdc2) _like Protein Is Localized in Both Nuclei and Cytoplasm of Physarum polycephalum

目前关于动物和酵母细胞中p34cdc2 的定位研究结果尚存在分歧 ,而关于该蛋白在植物细胞中的定位尚不清楚。以多头绒泡菌 (Physarumpolycephalum)S期、G2早期、G2中期、G2晚期、前期、中期和后末期的原质团和细胞核为材料进行免疫印迹 ,发现原质团和细胞核都含有一种分子量约 34kD的类p34cdc2 蛋白 ,该蛋白在原质团和细胞核中的含量在整个细胞周期进程中基本保持稳定。以抗p34cdc2 单克隆抗体为探针的免疫电镜结果显示 ,类p34cdc2 蛋白既分布于细胞核也分布于细胞质中 ,在细胞核中主要与染色体和核仁结合。经抗p34cdc2 单克隆抗体处理后 ,多头绒泡菌的有丝分裂启始迟滞约 2h。结果表明 ,多头绒泡菌类p34cdc2 蛋白存在于细胞核和细胞质中 ,与细胞有丝分裂密切相关 ,其含量在细胞周期进程中基本保持稳定。

全人源抗MLAA-34单链抗体的筛选和鉴定

目的:抗体药物治疗是目前癌症治疗中很有前景的一种方法,利用前期实验得到的MLAA-34纯化蛋白作为抗原,在噬菌体抗体库中进行筛选得到抗MLAA-34的单链抗体,进行测序并鉴定其亲和力。方法:包被纯化的MLAA-34抗原蛋白于96孔板上,封闭过夜,加入1×1012 cfu噬菌体抗体库,4℃结合4 h,洗脱,洗脱后的噬菌体感染大肠杆菌TG1扩增,经过3轮淘选,淘选得到的克隆再进行Phage-ELISA的鉴定,筛选得到阳性克隆。结果:纯化的MLAA-34作为抗原,经过在噬菌体抗体库中的3轮固相筛选,噬菌体的回收得到富集,洗脱的噬菌体产率显示回收率逐级增加,富集倍数约1000倍。最后一轮筛选后挑选出188个重组噬菌体克隆,His标签蛋白作为对照蛋白,应用Phage-ELISA筛选出33个阳性克隆。结论:利用得到的MLAA-34蛋白为目标抗原,对全人源噬菌体抗体库进行淘选,应用Phage-ELISA法挑选出和MLAA-34抗原结合力的阳性噬菌体,为抗MLAA-34抗体的制备奠定了基础。

应用单克隆抗体-免疫磁珠分离系统分离纯化再生障碍性贫血骨髓CD_(34)^+细胞

目的 分离、纯化再生障碍性贫血 (简称AA)患者骨髓CD3 4+ 细胞 ,探讨其发病机制。方法 对4 2例AA患者 ,以常规方法进行骨髓液采集和有核细胞分离 ,用单克隆抗体 免疫磁珠分离系统 (MACS)分离、纯化骨髓CD3 4+ 细胞 ,用碱性磷酸酶 抗碱性磷酸酶 (APAAP)法作CD3 4+ 细胞的纯度检测。结果 骨髓CD3 4+ 细胞纯度达 95 %～ 99% ,AA患者骨髓CD3 4+ 细胞多呈单个、散在分布 ,着色较淡 ;而对照组骨髓CD3 4+ 细胞多呈均匀或丛簇状分布 ,着色较深。结论 应用MACS分离AA骨髓CD3 4+ 细胞 ,特异性强、纯度高 ,是研究AA骨髓CD3 4+ 细胞功能、形态的最直接、客观。

CD_(34)抗体对特发性血小板减少性紫癜患者巨核系祖细胞作用的观察

应用CD_(34)抗体结合骨髓巨核系祖细胞(CFU—Meg)培养法观察了22例特发性血小板减少性紫癜(ITP)患者CFU—Meg的产率及CD_(34)抗原的表达。结果表明:ITP患者的巨核细胞产率与10例正常对照者差异不显著(P>0.05);CD_(34)抗体在体外对ITP及正常人CFU—Meg均有识别抑制作用,二者之间差异不显著。从而推测ITP的发病机理不在干细胞及祖细胞水平。

Induction of specific immunosuppression of cardiac allograft rejection withmonoclonal antibodies to CD44, LFA-1 and ICAM-1

Objective:To evaluate the immunosuppressive effect of monoclonal antibodies (McAb) against cell surface adhesion molecules on transplant rejection. Methods: C57BL/6 (H-2b) mouse cardiac grafts were transplanted into BALB/c(H- 2d) mice. This model was used to investigate the possibility of immunosuppressive induction with CD44 McAb, leukocyte function associated antigen (LFA-1) and intercellular adhesion molecule (ICAM-1). Results: Treatment of the allograft recipients with CD44 McAb alone, or both LFA-1 and ICAM-1 or combination of these 3 McAb significantly prolonged the cardiac allografts survival as compared with PBS controls (P<0.01). The combination of anti-CD44 and ICAM-1 and LFA-1 McAb was shown to produce more significant prolongation of grafts survival than anti-CD44 McAb alone or both anti-ICAM- 1 and LFA-1 McAb (P < 0.01). Histological examination of the grafts treated with the McAb displayed greatly reduced mononuclear cell infiltration. The proliferation of spleen cells from recipient BALB/c with McAb treatment was significantly inhibited in response to the stimulators of C57BL/6 spleen cells, but increased upon the stimulation of C3H/He (H-2k) spleen cells, as demonstrated by mixed lymphocyte reaction. Similarly, the cytotoxic activity against donor H-2-compatible (H-2b) target cells, EL-4 cells, was significantly suppressed. The spleen cells from allografted recipient BALB/c mice with McAb treatment induced specific tolerance for C57BL/6 cardiac grafts in allografted recipients, whereas those from allografted BALB/c mice without McAb treatment induced acute rejection. Conclusion: These results indicate that antiadhesion therapy using a combination of McAb to adhesion molecules can induce specific immunosuppression of transplant rejection.

Evaluation of teplizumab's efficacy and safety in treatment of type 1 diabetes mellitus:A systematic review and meta-analysis

BACKGROUND Islets of Langerhans beta cells diminish in autoimmune type 1 diabetes mellitus(T1DM).Teplizumab,a humanized anti-CD3 monoclonal antibody,may help T1DM.Its long-term implications on clinical T1DM development,safety,and efficacy are unknown.AIM To assess the effectiveness and safety of teplizumab as a therapeutic intervention for individuals with T1DM.METHODS A systematic search was conducted using four electronic databases(PubMed,Embase,Scopus,and Cochrane Library)to select publications published in peerreviewed journals written in English.The odds ratio(OR)and risk ratio(RR)were calculated,along with their 95%CI.We assessed heterogeneity using Cochrane Q and I2 statistics and the appropriate P value.RESULTS There were 8 randomized controlled trials(RCTs)in the current meta-analysis with a total of 1908 T1DM patients from diverse age cohorts,with 1361 patients receiving Teplizumab and 547 patients receiving a placebo.Teplizumab was found to have a substantial link with a decrease in insulin consumption,with an OR of 4.13(95%CI:1.72 to 9.90).Teplizumab is associated with an improved Cpeptide response(OR 2.49;95%CI:1.62 to 3.81)and a significant change in Glycated haemoglobin A1c(HbA1c)levels in people with type 1 diabetes[OR 1.75(95%CI:1.03 to 2.98)],and it has a RR of 0.71(95%CI:0.53 to 0.95).CONCLUSION In type 1 diabetics,teplizumab decreased insulin consumption,improved C-peptide response,and significantly changed HbA1c levels with negligible side effects.Teplizumab appears to improve glycaemic control and diabetes management with good safety and efficacy.

急性髓系白血病免疫治疗的研究进展与展望

大多数急性髓系白血病(acute myeloid leukemia,AML)患者化疗诱导缓解后不可避免地面临复发。异基因造血干细胞移植作为AML最有效的治疗,通过免疫介导的移植物抗白血病效应根除白血病细胞,能有效预防AML复发。移植技术和单倍体移植模式进展使得"人人都能进行造血干细胞移植"。靶向治疗,如基因工程T细胞(嵌合抗原受体T细胞)、单克隆抗体、新型双特异性单抗,能特异性杀伤表达特殊抗原的白血病细胞,而不伤害正常细胞,将成为AML免疫治疗的新策略。研究发现高表达于急性单核细胞白血病细胞的新抗原急性单核细胞白血病相关抗原-34(monocytic leukemia associated antigen-34,MLAA-34)具有抗白血病细胞凋亡作用,且MLAA-34多肽可诱导特异性CTL杀伤活性,具有较强的免疫原性,MLAA-34可作为急性单核细胞白血病免疫治疗新的理想靶抗原。总之,新近进展有价值的免疫治疗白血病相关抗原的鉴定有可能根除化疗后白血病微小残留病变,有望降低AML复发,延长AML患者生存。

Anti-cd TCR antibody-expanded cd T cells:a better choice for the adoptive immunotherapy of lymphoid malignancies

Cell-based immunotherapy for lymphoid malignancies has gained increasing attention as patients develop resistance to conventional treatments.cd T cells,which have major histocompatibility complex(MHC)-unrestricted lytic activity,have become a promising candidate population for adoptive cell transfer therapy.We previously established a stable condition for expanding cd T cells by using anti-cd T-cell receptor(TCR)antibody.In this study,we found that adoptive transfer of the expanded cd T cells to Daudi lymphoma-bearing nude mice significantly prolonged the survival time of the mice and improved their living status.We further investigated the characteristics of these antibody-expanded cd T cells compared to the more commonly used phosphoantigen-expanded cd T cells and evaluated the feasibility of employing them in the treatment of lymphoid malignancies.Slow but sustained proliferation of human peripheral blood cd T cells was observed upon stimulation with anti-cd TCR antibody.Compared to phosphoantigen-stimulated cd T cells,the antibody-expanded cells manifested similar functional phenotypes and cytotoxic activity towards lymphoma cell lines.It is noteworthy that the anti-cd TCR antibody could expand both the Vd1 and Vd2 subsets of cd T cells.The in vitro-expanded Vd1 T cells displayed comparable tumour cell-killing activity to Vd2 T cells.Importantly,owing to higher C–C chemokine receptor 4(CCR4)and CCR8 expression,the Vd1 T cells were more prone to infiltrate CCL17-or CCL22-expressing lymphomas than the Vd2 T cells.Characterizing the peripheral blood cd T cells from lymphoma patients further confirmed that the anti-cd TCR antibody-expanded cd T cells could be a more efficacious choice for the treatment of lymphoid malignancies than phosphoantigen-expanded cd T cells.

Treatment strategies for nodal and gastrointestinal follicular lymphoma:Current status and future development

In recent years,therapies for follicular lymphoma (FL) have steadily improved.A series of phase Ⅲ trials comparing the effect of rituximab with chemotherapy vs chemotherapy alone in treating FL have indicated significant improvements in progression-free survival (PFS) and overall survival.Recent studies have found that prolonged response durations and PFS were obtained with maintenance therapy using rituximab or interferon after completion of first line therapy.For patients with relapsed or refractory FL,phase Ⅱ studies have assessed the effectiveness of combination therapies using a Toll-like receptor-9 agonist (1018ISS),oblimersen sodium (a Bcl-2 antisense oligonucleotide),bendamustine,and rituximab,as well as veltuzumab,a new humanized anti-CD20 antibody,and epratuzumab.In addition,the effectiveness of yttrium-90 ibritumomab tiuxetan and iodine-131 tositumomab as radioimmunotherapies has been reported.Furthermore,three phase Ⅲ studies on an idiotype vaccine are near completion.Unfortunately,these vaccines,which appeared highly effective in phase Ⅰ and Ⅱ trials,do not appear to result in prolonged PFS.This report will summarize the current knowledge on therapies for treatment of FL,and will conclude with a brief discussion of feasiblefuture options for effective treatments.Lastly,we added descriptions of the management of gastrointestinal FL,which is considered to be controversial because it is rare.

A multi-center,open-label,randomized,parallel-controlled phase II study comparing pharmacokinetic,pharmacodynamics and safety of ripertamab(SCT400)to rituximab(Mab Thera?)in patients with CD20-positive B-cell non-Hodgkin lymphoma

Objective:This multi-center,open-label,randomized,parallel-controlled phaseⅡstudy aimed to compare the pharmacokinetics(PK),pharmacodynamics(PD)and safety profile of ripertamab(SCT400),a recombinant antiCD20 monoclonal antibody,to rituximab(MabThera^(■))in patients with CD20-positive B-cell non-Hodgkin lymphoma(NHL).Methods:Patients with CD20-positive B-cell NHL who achieved complete remission or unconfirmed complete remission after standard treatment were randomly assigned at a 1:1 ratio to receive a single dose of ripertamab(375mg/m^(2))or rituximab(MabThera^(■),375 mg/m^(2)).PK was evaluated using area under the concentration-time curve(AUC)from time 0 to d 85(AUC_(0-85d)),AUC from time 0 to week 1(AUC0-1 w),AUC from time 0 to week 2(AUC_(0-2 w)),AUC from time 0 to week 3(AUC_(0-3 w)),AUC from time 0 to week 8(AUC_(0-8 w)),maximum serum concentration(C_(max)),terminal half-life(T_(1/2)),time to maximum serum concentration(T_(max))and clearance(CL).Bioequivalence was confirmed if the 90%confidence interval(90%CI)of the geometric mean ratio of ripertamab/rituximab was within the pre-defined bioequivalence range of 80.0%-125.0%.PD,immunogenicity,and safety were also evaluated.Results:From December 30,2014 to November 24,2015,a total of 84 patients were randomized(ripertamab,n=42;rituximab,n=42)and the PK analysis was performed on 76 patients(ripertamab,n=38;rituximab,n=38).The geometric mean ratios of ripertamab/rituximab for AUC_(0-85d),ATC_(0-inf),and Cmaxwere 96.1%(90%CI:87.6%-105.5%),95.9%(90%CI:86.5%-106.4%)and 97.4%(90%CI:91.6%-103.6%),respectively.All PK parameters met the pre-defined bioequivalence range of 80.0%-125.0%.For PD and safety evaluation,there was no statistical difference in peripheral CD 19-positive B-cell counts and CD20-positive B-cell counts at each visit,and no difference in the incidence of anti-drug antibodies was observed between the two groups.The incidences of treatment-emergent adverse events and treatment-related adverse events were also comparable between the two groups.Conclusions:In this study,the PK,PD,immunogenicity,and safety profile of ripertamab(SCT400)were similar to rituximab(MabThera^(■))in Chinese patients with CD20-positive B-cell NHL.

Downregulation of CD4+CD25+ regulatory T cells may underlie enhanced Th1 immunity caused by immunization with activated autologous T cells

Regulatory T cells （Treg） play important roles in immune system homeostasis, and may also be involved in tumor immunotolerance by suppressing Th1 immune response which is involved in anti-tumor immunity. We have previously reported that immunization with attenuated activated autologous T cells leads to enhanced anti-tumor immunity and upregulated Thl responses in vivo. However, the underlying molecular mechanisms are not well understood. Here we show that Treg function was significantly downregulated in mice that received immunization of attenuated activated autologous T cells. We found that Foxp3 expression decreased in CD4＋CD25＋ T cells from the immunized mice. Moreover, CD4＋CD25＋Foxp3＋ Treg obtained from immunized mice exhibited diminished immunosuppression ability compared to those from naive mice. Further analysis showed that the serum of immunized mice contains a high level ofanti-CD25 antibody （about 30 ng/ml, p〈0.01 vs controls）. Consistent with a role ofanti-CD25 response in the downregulation of Treg, adoptive transfer of serum from immunized mice to naive mice led to a significant decrease in Treg population and function in recipient mice. The triggering of anti-CD25 response in immunized mice can be explained by the fact that CD25 was induced to a high level in the ConA activated autologous T cells used for immunization. Our results demonstrate for the first time that immunization with attenuated activated autologous T cells evokes anti-CD25 antibody production, which leads to impeded CD4＋CD25＋Foxp3＋ Treg expansion and function in vivo. We suggest that dampened Treg function likely contributes to enhanced Thl response in immunized mice and is at least part of the mechanism underlying the boosted anti-tumor immunity.

Targeting and Internalization of Sterically Stabilized Liposome Modified with ZCH-4-2E8

Sterically stabilized liposome （SL） modified with 2E8 monoclonal antibody （2E8-SL） was prepared in order to evaluate its targeting ability and internalization efficiency against tumor cells with high expression of CD19.2E8 was coupled to the surface of SL using post-insertion technique. The shape of liposomes was observed under a transmission electronic microscope. The average size of liposomes was determined by using the Zetasizer instrument. The binding and internalization of 2E8-SL against tumor cells with higher expression of CD 19 were tested by flow cytometry and confocal microscopy. The mean diameter of 2E8-SL was 121.25 nm. 2E8-SL was stable after up to 24 days in various buffers. 2ES-SL showed specific binding to tumor cells with high expression of CD19, including B cells in peripheral blood mononuclear cells （PBMCs）. 2E8-SL could efficiently internalize into Nalm6 cells with CD19 high expression. It is suggested that 2E8-SL may serve as useful delivery carrier of anti-cancer drugs targeting to hematological malignant tumors with CD 19 high expression.

Biodistribution and Anti-tumor Activities of the ^(131)I-labeled Rituximab in Nude Mice Bearing Human Burkitt's lymphoma

OBJECTIVE To explore the biodistribution and anti-tumoractivity of ^(131)I labeled rituximab injected intratumorally orintraperitoneally in vivo in nude mice bearing Raji human Burkitt's lymphoma xenografts.METHODS The rituximab and the mouse IgG were labeled withNa^(131)I using the IODO-GEN method.BALB/C nude mice werexenografted with ^(131)I-Rituximab or ^(131)I-IgG and killed on the 1st,3rd,7th,and 15th day after injection.The tumor/non-tumor ratio(T/NT)and the dose injected in each gram of the tissue(%ID/g)from12 organs or tissues of interest,e.g.tumor,blood,were calculated.The long and short axes of each tumor were measured by calipersat 2-3-day intervals after treatment,and the growth inhibition ofthe tumor was calculated using the MIRD formula.RESULTS When comparing intraperitoneal injection(IP)andintratumoral injection(IT)of ^(131)I-IgG,intratumoral injection of^(131)I-rituximab produced a significantly higher tumor/non-tumorratio in all tissues and organs of interest on the 1st,3rd,and 7thday,respectively(P<0.05).The %ID/g of tumor was 1.4-1.7-foldand 1.5-3.7-fold in the IP and IgG IT groups,respectively,but the%ID/g of non-tumors was significantly lower in the IP group andIgG IT group.Similarly,the tumor growth was greatly inhibitedby intratumoral injection of the ^(131)I-rituximab,whereas it wasless inhibited by other forms of the treatment(P<0.05).However^(131)I-rituximab injected intratumorally inhibited tumor growth ina dose-dependent manner.The inhibition rate was less with alow dose(75μCi)and greater with a high dose(150μCi),yet thedifference was not significant(P>0.05).CONCLUSION Tumors can absorb the highest amount of theradiolabelled antibodies,and the tumor/non-tumor ratios in thegroup with intratumoral injection of the ^(131)I-rituximab resulted inthe optimal anti-tumor activity.