ELISPOT检测人乳头瘤病毒特异性的记忆T细胞

应用ELISPOT方法检测人乳头瘤病毒感染后自发清除者外周血中抗原特异性的记忆T细胞。收集人乳头瘤病毒（HPV）感染后自发清除者外周血（病毒清除后74个月）,分离外周血单个核细胞（peripheralblood mononuclear cells,PBMC）。体外应用已鉴定的表位肽刺激PBMC,10 d后计数细胞,去除表位肽,继续培养。第11天,ELISPOT方法检测PBMC中HPV抗原特异性的记忆T细胞。PBMC经表位肽刺激10 d后,细胞数量有明显增加,由最初的4.1×105增加为4.2×106。第11天,细胞数量增加为4.65×106,为抗原刺激前细胞数的11.3倍。ELISPOT结果显示,PBMC中的记忆T细胞活化后,能够识别抗原递呈细胞递呈的抗原肽,并分泌IFN-γ。此HPV自发清除者外周血中抗原特异性的记忆T细胞的频数为0.007%。人乳头瘤病毒（HPV）感染后自发清除者外周血存在抗原特异性记忆T细胞,抗原肽可激活记忆T细胞,使之数量增加,分泌IFN-γ。ELISPOT可用于检测外周血中HPV特异性的记忆T细胞。     

含HTNV S基因重组痘苗病毒在HFRS患者B淋巴母细胞系中的表达

采用Ficoll密度梯度离心法(淋巴细胞分离液)分离肾综合征出血热(HFRS)患者外周血单个核细胞（PBMC),并用EB病毒(EBV)感染B淋巴细胞,建立永生化的B淋巴母细胞系(B—LCL)。然后,用含汉滩病毒(Hantaan virus,HTNV)S基因的重组痘苗病毒感染B—LCL,应用问接免疫荧光检测核衣壳蛋白的表达。结果表明,B淋巴细胞经EBV感染4周左右,可形成永生化B—LCL。成功转化后的B—LCL,体积增大,且增殖的淋巴细胞积聚成团。汉滩病毒S基因在B—LCL中能有效表达核衣壳蛋白。含S基因的重组痘苗病毒感染的B—LCL可用作HTNV核衣壳蛋白特异性CTL活性研究的靶细胞。     

Epstein-Barr病毒特异性T细胞对重组痘苗病毒表达LMP和EBNA2的靶细胞的识别

本文用EB病毒转化自体淋巴细胞所建立的类淋巴母细胞系(LCL),以及用EB病毒潜伏感染膜蛋白(LMP)基因和核蛋白-2(EBNA2)基因与痘苗病毒重组的重组病毒(Vac-LMP和Vac-EBNA2)感染的自身纤维母细胞,同时作为刺激细胞和靶细胞,以~(51)Cr释放法检测5例血清中EB病毒VCA—IgA抗体阳性者及1例阴性健康者外周血单个核细胞(PBMC)的特异性T细胞杀伤效应。结果表明,用自身LCL激活的EB病毒特异性T细胞杀伤效应高峰出现在第14～28天;参与杀伤性细胞免疫反应的T细胞亚群主要是T3、T8阳性的细胞毒性T细胞,其对靶细胞的识别及杀伤受HLA-I的限制。用重组牛痘病毒感染的纤维母细胞作靶细胞或刺激细胞,有1例供者可接受LMP,另1例可接受EBNA2的刺激,并对相应的靶细胞产生特异性T细胞杀伤反应,表明EB病毒-LMP和EBNA2可能既是EB病毒特异性T细胞的刺激抗原,又是其识别的靶抗原。     

鼻咽癌病人和正常人群中EB病毒特异性T细胞对靶抗原的识别和应答

为探讨痘苗病毒表达的Eoskein-Barr病毒（EBV）核抗原1、4（EBNA1、4）和潜伏膜蛋白1、2（LMP1、2）,在不同人群的特异性T细胞杀伤9CTL）中的作用,采集EBV阴性正常人、未经治疗的鼻咽癌（NPC）病人的EBV－IgA/VCA阳性者各10人的周围血淋巴单核细胞（PBMC）,用EBV转化B淋巴细胞,建立类淋巴母细胞（LCL）,用LCL刺激自休的T淋巴细胞作为效应细胞,以LCL感染重组痘苗病毒表达的EBNA1、4和LMP1、2为靶细胞,以^51Cr释放法检测EBV特异性CTL所识别的靶抗原。结果表明,EBV－LMP1、2可能既是EBV特异性T细胞的刺激抗原,又是其识别的靶抗原。将采集的30例试验者的各5 单克隆T细胞株分别检测HLA-Ⅰ型（A、B、C）,按照不同型别寻找相对应的EBNA1、4和LMP1、2的不同合成肽,应用酶免疫吸附斑点法（Elispot）检测EBV特异性CD8^ 的CTL应答。结果显示：10例正常人中9人有特异的LMP2应答,4人有特异的EBNA4应答;10例未治疗的NPC病人中3人有特异的LMP2,2人有特异的EBNA1,3个有特异的EBNA4应答;10例未治疗的NPC病人中3人有特异的EBNA1,3人有特异的EBNA4应答,在10例EBV－IgA/VCAbj ntg k ,6人有特异的LMP2,5人有特异的EBNA4应答。所有的试验者均未发现LMP1的特异性应答。     

含HTNV S基因重组痘苗病毒在HFRS患者B淋巴母细胞系中的表达

采用Ficoll密度梯度离心法(淋巴细胞分离液)分离肾综合征出血热(HFRS)患者外周血单个核细胞(PBMC),并用EB病毒(EBV)感染B淋巴细胞,建立永生化的B淋巴母细胞系(B-LCL).然后,用含汉滩病毒(Hantaan virus ,HTNV) S基因的重组痘苗病毒感染B-LCL,应用间接免疫荧光检测核衣壳蛋白的表达.结果表明,B淋巴细胞经EBV感染4周左右,可形成永生化B-LCL.成功转化后的B-LCL,体积增大,且增殖的淋巴细胞积聚成团.汉滩病毒S基因在B-LCL中能有效表达核衣壳蛋白.含S基因的重组痘苗病毒感染的B-LCL可用作HTNV核衣壳蛋白特异性CTL活性研究的靶细胞.     

Tetramer技术检测人乳头瘤病毒抗原特异性T细胞条件的优化

人乳头瘤病毒(human papillomavirus,HPV)感染是宫颈癌发生的首要因素。针对病毒早期蛋白E6的特异性细胞毒性T淋巴细胞(cytotoxic Tlymphocyte,CTL)在清除HPV感染细胞和病毒转化形成的肿瘤细胞过程中发挥重要作用,因此检测体内抗原特异性CTL的频数和功能有助于了解病毒感染者或宫颈癌患者体内的特异性细胞免疫反应。利用加载HPV16 E6表位抗原肽(E6 133-142;HNIRGRWTGR)的HLA-A6801四聚体(Tetramer),即HPV16 E6 133-142/HLA-A6801-PE四聚体,通过检测混有HPV特异性CTL的PBMC标本,优化Tetramer染色的实验条件,探讨染色的最佳温度及Tetramer浓度。结果显示,染色温度(4℃、室温及37℃)对Tetramer与CTL的结合无明显影响。Tetramer稀释度为1∶1 600时,HPV特异性CTL荧光强度保持高水平,且非特异性染色少,为最佳染色浓度。研究结果为进一步检测HPV感染者或宫颈癌患者体内抗原特异性的CTL打下基础。     

含结构性倒位inv（5）（p13.1 q13.3）的毛细胞白血病细胞系的建立

为从分子水平揭示毛细胞白血病（HCL）的发病机理提供研究材料,将患者外周血淋巴细胞分离,用EBV病毒转化后进行细胞培养,建立细胞系,在连续传代3个月后,进行染色体组型分析,所培养细胞的染色体组型分析结果,与患者新鲜的外周血淋巴细胞的完全相同,证实该细胞系构建成功。     

NIH3T3-CD40L稳定细胞系构建及在EBV转化B淋巴细胞中的应用

通过脂质体法转染p CMV6-CD40L重组质粒和G418阳性克隆筛选,构建了稳定表达CD40L的NIH3T3细胞系,在RNA和蛋白质水平进行了功能鉴定,对其作为饲养细胞在体外B淋巴母细胞系(B lymphoblastoid cell lines,B-LCLs)培养和在EBV转化B细胞中的作用进行了实验验证。结果表明,NIH3T3-CD40L细胞系不仅可以提高体外低密度B-LCLs存活率,而且可以降低成功建立B-LCLs所需的细胞密度,促进其增殖。该细胞系的成功构建,进一步确证了NIH3T3-CD40L作为饲养细胞可以促进体外低密度B-LCLs的增殖及提高EBV转化B淋巴细胞的效率,优化了体外B细胞培养及EBV转化B淋巴细胞的流程,也为单克隆抗体的制备奠定了基础。     

从HFRS患者的PBMC建立BLCL及其意义

体外研究汉滩病毒(Hantaan virus,HTNV)S基因及其5'端、3'端在BLCL(EBV-transformed Blymphoblastoidcellline,BLCL)内稳定表达的意义,为核蛋白T细胞表位的研究奠定基础.本研究从肾综合征出血热(HFRS)患者的外周血单个核细胞(PBMC)建立与HTNV特异性CTL同源的患者自身的EB病毒转化的B淋巴母细胞系,将含有不同HTNV S基因片段的重组真核表达载体转染入BLCL,获得长期稳定表达,作为靶细胞系,为下一步进行CTL杀伤试验提供靶细胞系.设计4条引物,用PCR方法从PBV220-S22原核质粒中扩增出S基因全读码框(37-1326bp)及S基因5'端(37-501bp),S基因3'端(502-1326bp),用TA克隆将其克隆入pcDNA3.1/V5-His-TOPO载体中,成功构建pcDNA3.1-S及pcDNA3.1-S-N、pcDNA3.1-S-C真核表达载体,并通过脂质体转染至BLCL细胞中,进行了稳定表达.间接免疫荧光成功检测到pcDNA3.1-S及pcDNA3.1-S-N、pcDNA3.1-S-C在BLCL细胞中的表达.pcDNA3.1-S及pcDNA3.1-S-N、pcDNA3.1-S-C真核表达载体有较高的转染效率,目的基因能在宿主细胞中长期稳定表达,有利于研究HTNV-S基因在T细胞表位研究中的意义.建立的特异性CTL克隆对表达完整NP、NP羧基和氨基端肽段的靶细胞均有比较明显的杀伤效应,平均杀伤率分别为50.2%、39.0%和25.4%.HTNV-NP优势T细胞表位可能主要位于病毒核蛋白的羧基端.     

用Epstein-Barr病毒转化技术建立分泌人单克隆抗体B淋巴细胞系的条件

用以去除T淋巴细胞的E—玫瑰花形成法中所用的羊红细胞(SRBC),其保鲜程度对EB病毒转化B淋巴细胞的结果有一定影响,用保存1天的SRBC者,转化细胞的抗体分泌时间较长(8～10周),并且能形成传代细胞系;用保存17天的SRBC,转化细胞的抗体分泌时间较短,未能无限传代。分离外周血单个核细胞时,保留自体粘附细胞作为饲养细胞,转化的细胞二个月的成活率可达75％,而不保留粘附细胞者,转化细胞成活率仅40％。能产生抗-HBc抗体的EBV转化细胞,自然分泌抗体时间一般不超过10周,高峰期在3周以内,第2周时最高。EB病毒感染后的转化细胞5天开始克隆,一般细胞难成活,在14天克隆的,成活率可达100％。21天开始克隆的转化细胞,免疫球蛋白自然分泌维持12周以上,而在35天开始克隆的细胞,维持分泌的时间都不超过10周。以未经γ线照射的小鼠腹腔渗出细胞作饲养细胞,可支持转化3周的细胞克隆扩增,克隆成活率可达100％,而对照组克隆成活率仅为64.7％。     

Two distinct human cloned T cell lines that exhibit natural killer-like and anti-human effector activities

Cloned T cell lines from mixed lymphocyte cultures stimulated with autologous Epstein Barr virus- (EBV) transformed lymphoblastoid cell line (LCL) cells were established using a limiting dilution technique in the presence of T cell growth factor (TCGF). The T cell lines included two distinct clones of cytotoxic T cells (Tc) in addition to EBV-specific Tc. A cytotoxic profile of one cloned line was similar to that of endogenous NK cells in peripheral blood. The other cloned Tc line showed an anti-human cytotoxicity. The susceptible targets for this latter Tc line were various human cells, including autologous LCL and peripheral blood lymphocytes (PBL), stimulated with pokeweed mitogen, along with NK-sensitive and NK-resistant cell lines. Weak cytotoxic activity was detected against various xenogeneic cell lines. Furthermore, autologous and allogeneic cloned T cell lines were resistant to killing by the anti-human effector clone. These t wo distinct cloned Tc lines expressed the Leu-1 and Leu-2a antigens, which are markers of suppressor/cytotoxic T cells.     

HLA-A2-restricted peripheral blood cytolytic T lymphocyte response to HPV type 16 proteins E6 and E7 from patients with neoplastic cervical lesions

 The DNA from human papillomavirus (HPV) can be detected in 90% of cervical carcinomas. To address whether patients infected with HPV can mount efficient T cell responses to this pathogen we examined the cytotoxic T lymphocyte (CTL) response of peripheral blood mononuclear cells (PBMC) from patients with abnormal genital epithelial cells. PBMC from 11 HLA-A2⁺ patients were stimulated with CaSki, a cervical carcinoma cell line that is HPV 16⁺ and HLA-A2⁺. The CTL were screened for reactivity to the cervical carcinoma cell line C33A (HPV^–, HLA-A2⁺) transfected with the HPV 16 E6 or E7 genes or the plasmid without insert. The CTL of 1 patient showed particularly strong CaSki and HPV E6 or E7 protein-specific cytotoxicity in a HLA-A2-restricted fashion. In contrast, these CTL lysed neither a vector-only transfectant, the natural killer cell (NK) target, K562 nor the lymphokine-activated killer cell (LAK) target, Daudi. HLA-A2 restriction was demonstrated by the lack of recognition of a HLA-A2^– CaSki cell line developed in our laboratory. The CTL line was cloned and 99 clones were harvested and screened; 51 clones lysed CaSki, of which 17 did not lyse the A2^– CaSki. Of these HLA-A2^– restricted clones, 8 did not lyse C33A transfectants, 6 lysed all C33A transfectants, 3 lysed C33A-E7 only and none lysed C33A-E6 only. These data imply that, within the bulk CTL line, HLA-A2-restricted recognition of antigens was restricted to CaSki antigens, antigens common to cervical carcinoma (CaSki plus C33A), or HPV-16-E7-derived antigen on the clonal level. The E7-restricted clones were negative for recognition of known HLA-A2-binding peptides from E7. Received: 16 November 1995 / Accepted: 15 January 1996     

Heterogeneity of allogeneic restriction of human cytotoxic T cell clones specific for Epstein Barr virus

Clones of human cytotoxic T cells (Tc) specific for Epstein Barr virus (EBV) were isolated from peripheral blood lymphocyte (PBL) cultures stimulated repeatedly with autologous EBV-transformed lymphoblastoid cell line (LCL) cells in vitro. The method employed to clone EBV-specific Tc was a limiting dilution technique utilizing T cell growth factor (TCGF). The EBV specificity of Tc clones was determined by showing that they were significantly cytotoxic for autologous LCL cells but not for either autologous PBL or (natural killer-sensitive) K-562 cells. Eight EBV-specific Tc clones derived from a single donor exhibited distinct cytotoxic patterns against allogeneic LCL targets. Two clones were cytotoxic to LCL targets sharing both HLA-A26 and B15 antigens with effectors, and killing by two other clones was strongly restricted to autologous LCL cells. The four remaining clones showed cytotoxicities against various allogeneic LCL targets irrespective of HLA antigen expression. Eight EBV-specific Tc clones derived from a second donor also exhibited a wide spectrum of cytotoxicity to allogeneic LcL targets. We conclude that EBV-specific Tc, induced in vitro, consist of a number of clones with respect to restrictions imposed by the major histocompatibility complex. The determinants regulating these restrictions may include not only private HLA antigenic determinants that are defined by the HLA serotyping, but also undefined HLA antigenic determinants.     

Human papilloma virus–specific T cells can be generated from naïve T cells for use as an immunotherapeutic strategy for immunocompromised patients

Human papilloma virus (HPV) is a known cause of cervical cancer, squamous cell carcinoma and laryngeal cancer. Although treatments exist for HPV-associated malignancies, patients unresponsive to these therapies have a poor prognosis. Recent findings from vaccine studies suggest that T-cell immunity is essential for disease control. Because Epstein-Barr Virus (EBV)-specific T cells have been highly successful in treating or preventing EBV-associated tumors, we hypothesized that the development of a manufacturing platform for HPV-specific T cells from healthy donors could be used in a third-party setting to treat patients with high-risk/relapsed HPV-associated cancers. Most protocols for generating virus-specific T cells require prior exposure of the donor to the targeted virus and, because the seroprevalence of high-risk HPV types varies greatly by age and ethnicity, manufacturing of donor-derived HPV-specific T cells has proven challenging. We, therefore, made systematic changes to our current Good Manufacturing Practice (GMP)-compliant protocols to improve antigen presentation, priming and expansion for the manufacture of high-efficacy HPV-specific T cells. Like others, we found that current methodologies fail to expand HPV-specific T cells from most healthy donors. By optimizing dendritic cell maturation and function with lipopolysaccharide (LPS) and interferon (IFN)γ, adding interleukin (IL)-21 during priming and depleting memory T cells, we achieved reliable expansion of T cells specific for oncoproteins E6 and E7 to clinically relevant amounts (mean, 578-fold expansion; n?=?10), which were polyfunctional based on cytokine multiplex analysis. In the third-party setting, such HPV-specific T-cell products might serve as a potent salvage therapy for patients with HPV-associated diseases.     

MOB2基因在真核细胞中的表达研究

通过RT-PCR从培养的HUVECs中扩增MOB2基因片段,将该片段克隆在真核表达载体pEGFP-C1中,转染NIH3T3细胞,经G418筛选,构建稳定表达细胞系,并用荧光显微镜和Western blot对其进行鉴定。经RT-PCR扩增出734 bp基因片段,经测序分析并与GenBank的DNA序列比对分析后,在NIH3T3细胞中表达。G418筛选后,细胞荧光信号较强,Western blot检测,细胞中的融合蛋白能够与抗MOB2的多抗结合。成功地扩增了HUVECs中的MOB2基因全长cDNA并进行真核表达与鉴定。     

Regression of Epstein-Barr virus-induced B-cell transformation in vitro involves virus-specific CD8+ T cells as the principal effectors and a novel CD4+ T-cell reactivity

T-cell memory to Epstein-Barr virus (EBV) was first demonstrated through regression of EBV-induced B-cell transformation to lymphoblastoid cell lines (LCLs) in virus-infected peripheral blood mononuclear cell (PBMC) cultures. Here, using donors with virus-specific T-cell memory to well-defined CD4 and CD8 epitopes, we reexamine recent reports that the effector cells mediating regression are EBV latent antigen-specific CD4+ and not, as previously assumed, CD8+ T cells. In regressing cultures, we find that the reversal of CD23+ B-cell proliferation was always coincident with an expansion of latent epitope-specific CD8+, but not CD4+, T cells; furthermore CD8+ T-cell clones derived from regressing cultures were epitope specific and reproduced regression when cocultivated with EBV-infected autologous B cells. In cultures of CD4-depleted PBMCs, there was less efficient expansion of these epitope-specific CD8+ T cells and correspondingly weaker regression. The data are consistent with an effector role for epitope-specific CD8+ T cells in regression and an auxiliary role for CD4+ T cells in expanding the CD8 response. However, we also occasionally observed late regression in CD8-depleted PBMC cultures, though again without any detectable expansion of preexisting epitope-specific CD4+ T-cell memory. CD4+ T-cell clones derived from such cultures were LCL specific in gamma interferon release assays but did not recognize any known EBV latent cycle protein or derived peptide. A subset of these clones was also cytolytic and could block LCL outgrowth. These novel effectors, whose antigen specificity remains to be determined, may also play a role in limiting virus-induced B-cell proliferation in vitro and in vivo.     

8-Oxoguanine DNA-glycosylase repair activity and expression: a comparison between cryopreserved isolated lymphocytes and EBV-derived lymphoblastoid cell lines

Several lines of evidence suggest an association between oxidative DNA-damage repair capacity and cancer risk. In particular, a DNA-glycosylase assay for removal of 8-oxoguanine (8-oxoG) in peripheral blood mononuclear cells (PBMC) has been successfully applied to identify populations with increased risk for lung cancer and squamous cell carcinomas of head and neck. In order to verify whether EBV-transformed lymphoblastoid cell lines (LCL) are a suitable surrogate for PBMC in specific DNA-repair phenotypic assays, a validation trial was conducted. PBMC from 20 healthy subjects were collected and an aliquot was transformed with EBV to obtain LCL. The ability of cell-free extracts from both cell types to incise a 3'-fluorescently labelled duplex oligonucleotide containing a single 8-oxoG (OGG assay) was evaluated. Since this activity is mediated predominantly by OGG1, the OGG1 gene expression was also measured. 8-oxoG DNA-glycosylase activity and OGG1 expression were significantly higher (p<0.0001) in LCL than in PBMC. However, while this assay was shown to be robust and reproducible when used on PBMC (intra-assay CV=8%), a high intra-culture variability was observed with LCL (intra-culture CV=16.8%). Neither differences on OGG1 gene expression nor the cell-cycle distribution seemed to account for this variability. Inter-individual variability of OGG activity in PBMC and LCL was not associated with OGG1 gene expression. We have therefore established a non-radioactive cleavage assay that can be easily applied to measure OGG activity in human PBMC. The use of LCL for DNA-repair genotype-phenotype correlation studies seems to be inappropriate, at least with cell-free based functional assays.     

Decreased HPV-specific T cell responses and accumulation of immunosuppressive influences in oropharyngeal cancer patients following radical therapy

Oropharyngeal cancer (OPC) is a type of squamous cell head and neck cancer that is often associated with human papillomavirus (HPV) infection, suggesting the potential for immunotherapeutic targeting of HPV antigens. This study aimed to determine the effect of radical therapy on HPV-specific T cells and other immune parameters in 20 OPC patients, as a prelude to future immunotherapy studies. HPV DNA could be detected in 9/12 available tissue samples (8/9 HPV⁺ samples were also p16⁺). HPV-specific T cell responses against HPV16 E6 and E7 peptides were detected by enzyme-linked immunoSPOT in 10/13 and 8/13 evaluable patients, respectively, but did not appear to correlate with HPV status. Post-treatment, both HPV E6 and E7 T cell responses were decreased (4/13 and 2/13 patients, respectively). These reductions in T cell response could not be explained by a concurrent decrease in memory T cells whose absolute numbers were relatively unaffected by radical therapy (27,975 vs. 25,661/10⁵ PBMC) despite a significant decrease in overall lymphocyte counts (1.74 vs. 0.69 × 10⁹/L). Instead, there were significant increases in regulatory T cells (3.7 vs. 6.8 %) and a population of myeloid-derived suppressor cells (CD14^?HLA-DR^?CD15^hi, 12.38 vs. 21.92 %). This suggests that immunosuppression may contribute to the reduction in HPV-specific T cell responses post-treatment, although study of larger patient cohorts will be required to test whether this affects clinical outcome. Overall these findings suggest that HPV-targeted immunotherapy in post-therapy OPC patients will require multiple strategies to boost T cell immunity and to overcome the influence of immunosuppressive cells.     

Antigen-specific and MHC-restricted Plasmodium falciparum-induced human T lymphocyte clones

We established and analyzed human T lymphocyte clones induced by crude Plasmodium falciparum antigens of schizont-enriched asexual blood stages. Peripheral blood mononuclear cells (PBMC) were stimulated for 6 days with antigen, and the T cell blasts were separated and were transferred to limiting dilution cultures with antigen, irradiated PBMC, and recombinant interleukin 2. The following observations were made. Malaria antigen (M.Ag) induced similar proportions of T blasts in PBMC from infected individuals and noninfected controls, and the M.Ag-dependent clone frequencies (1/79 to 1/216) obtained with the blasts were similar. The majority of established clones derived from infected and noninfected subjects specifically recognized M.Ag and would not proliferate in response to red blood cells or autologous PBMC alone. They also required HLA class II determinant-compatible antigen-presenting (E-) cells. With three clones from one malaria patient, DR 1 or DR 5 specificities correlated with antigen presentation. Although T4+ and T8+ blasts were induced by M.Ag in PBMC, only T4 (Leu-3+) clones were obtained in our culture system. These clones secreted IL 2 in response to M.Ag. 4) Differential patterns of reactivity to native M.Ag, heat-stable antigens, and heat-precipitated antigens were exhibited by T cell clones, and the tested clones did not recognize Plasmodium berghei antigen. In conclusion, it is important with regard to previous observations on apparently nonspecific, mitogen-like effects of M.Ag in bulk T cell cultures that our results demonstrate specific recognition of P. falciparum by human T cells. The T cell clones obtained will be an important tool in the quest for a better understanding of the mechanisms involved in resistance to malaria infection.     

Establishment and characterization of Macaca fascicularis lymphoblastoid cell lines.

A panel of cynomolgus macaque lymphoblastoid cell lines (LCL) was established by transforming peripheral blood mononuclear cells (PBMC) with Herpesvirus papio (HVP), and selected lines were examined by flow cytometry. Results indicate that HVP-transformed macaque LCL are phenotypically heterogeneous and resemble human Epstein-Barr virus (EBV)-transformed LCL in the abundant expression of major histocompatibility complex (MHC) class I and class II molecules. At least some lines are of B cell origin.