人白细胞介素—6与肿瘤坏死因子突变体融合蛋白对人骨…

本文报道了一种高活性人肿瘤坏死因子（ＴＮＦ）突变体与人白细胞介素－６（ＩＬ－６）的融合蛋白在大肠杆菌中表达产物的纯化及其对Ｌ９２９细胞和人骨髓瘤细胞的细胞毒作用。结果表明，该融合蛋白既具有ＴＮＦ抗肿瘤活性，又具有对高表达ＩＬ－６受体的肿瘤细胞特异性的杀伤作用。     

人疱疹病毒6型诱导单核细胞产生IL-10

目的探讨人疱疹病毒６型（ＨＨＶ－６）感染的免疫发病机理。方法用逆转录－聚合酶链反应（ＲＴ－ＰＣＲ）和双抗体夹心酶联免疫吸附试验（ＥＬＩＳＡ）检测白细胞介素－１０（ＩＬ－１０）等细胞因子的产生。结果ＨＨＶ－６诱导单核细胞表达和产生ＩＬ－１０，细胞因子ｍＲＮＡ动力学研究发现ＴＮＦ－α（肿瘤坏死因子）、ＩＬ－１β及ＩＬ－６随ＩＬ－１０ｍＲＮＡ积累而减少，用抗人ＩＬ－１０单克隆抗体阻断ＨＨＶ－６诱导的内源性ＩＬ－１０，ＴＮＦ－α、ＩＬ－１β和ＩＬ－６ｍＲＮＡ的表达和因子产生明显增加，表明ＨＨＶ－６诱导的内源性ＩＬ－１０在转录水平能抑制单核细胞因子产生。结论ＩＬ－１０具有抑制Ｉ类辅助性Ｔ细胞（Ｔｈ１）反应、下调单核巨噬细胞功能等多种生物作用，推测ＨＨＶ－６诱导产生的内源性ＩＬ－１０与该病毒长期潜伏感染及其参予的免疫功能紊乱有关。     

烧伤病人TNF,IL—6的变化与氧自由基关系的研究

研究烧伤后ＴＮＦ、ＩＬ－６的变化与氧自由基的关系。采用酶标法检测血清ＴＮＦ和ＩＬ－６，改良八木国夫法检测血清ＭＤＡ，动态观察了烧伤病人伤后１０ｄ内血清ＴＮＦ、ＩＬ－６和ＭＤＡ的变化以及抗氧化剂对血清ＴＮＦ和ＩＬ－６的影响。结果显示烧伤病人血清ＴＮＦ、ＩＬ－６和ＭＤＡＦ均显著增高（Ｐ〈０．０１）；ＴＮＦ与ＭＤＡ的变化呈正相关（ｒ＝０．４５，Ｐ〈０．０５）；抗氧化剂可降低血清ＴＮＦ（Ｐ〈０．０５）和Ｉ     

急性白血病患者IL—6,TNF—α和sIL—6R含量及其与白血病负荷的？…

应用生物学检测法，ＥＬＩＳＡ法和间接免疫荧光分析了２４例急性白血病患者外周血ＩＬ－６，ｓＩＬ－６Ｒ和ＴＮＦ－α的含量及其与白血病细胞负荷的相关性。结果显示：（１）急性白血病患者外周血ＩＬ－６，ｓＩＬ－６Ｒ及ＴＮＦ－α水平明显升高，其中急性Ｂ淋巴性白血病的ＩＬ－６，ｓＩＬ－６Ｒ急性Ｔ淋巴性白血病的ＴＮＦ－升高尤为明显；（２）Ｂ－ＡＬＬ的ＩＬ－６，ＴＮＦ－α及Ｔ－ＡＬＬ的ＴＮＦ－α水平与白血病细胞负     

抗细菌核心糖脂域McAb对LPS体外诱导细胞释放TNF－α和IL－6及其mRNA表达的影响

用细胞因子活性检测，Ｎｏｒｔｈｅｒｎｂｌｏｔ方法，在体外研究了抗细菌核心糖脂域ＭｃＡｂ（ＥＬ１、ＥＬ３和３Ｈ４）对ＬＰＳ诱导人外周血单核细胞（ｈＰＢＭＣ）释放ＴＮＦ－α和ＩＬ－６及其ｍＲＮＡ表达水平的影响。结果表明，ＥＬ１、ＥＬ３和３Ｈ４在体外有抑制ＬＰＳ诱导细胞释放ＴＮＦ－α和ＩＬ－６的作用；Ｎｏｒｔｈｅｒｎｂｌｏｔ结果证实，这３株ＭｃＡｂ能分别降低细胞ＴＮＦ－α和ＩＬ－６ｍＲＮＡ表达的水平；提示抗细菌核心糖脂域ＭｃＡｂ可能通过与ＬＰＳ的结合而中和ＬＰＳ，从而降低或阻碍了效应细胞炎性细胞因子ｍＲＮＡ的表达，达到降低相应细胞因子的作用。     

TPA及细胞因子对U937细胞中IL—1β mRNA表达的影响

本文利用Ｎｏｒｔｈｅｒｎ杂交法，检测了几种细胞因子及ＴＰＡ对人单核细胞白血病传代细胞系Ｕ９３７细胞中ＩＬ－１βｍＲＮＡ表达的影响。结果显示，ＴＮＦ－α，ＩＬ－６，ＩＦＮ－γ，ＩＬ－２，ＩＬ－３，ＩＬ－８，ＩＬ－９和ＧＭ－ＣＳＦ对ＩＬ－１βＲＮＡ的表达，均有不同程度的刺激作用，尤以ＴＮＦ－α和ＩＬ－６最为明显，ＴＰＡ刺激Ｕ９３７细胞表达ＩＬ－１β ｍＲＮＡ的时间效应显示，１２ｈ表达量较高；９ｈ表达     

逆转录病毒介导的IL－2和TNF－α融合基因在卵巢癌细胞中的表达及其对肿瘤细胞生长的影响

ＩＬ－４和ＴＮＦ－α是引人注目的抗肿瘤活性因子，两者在抗肿瘤及免疫调节方面具有协同作用。我们利用逆转录病毒载体Ｘｄ１构建了插入ＩＬ－２和ＴＮＦ－α融合基因的重组逆转录病毒载体ＸｄＦ，融合基因包括编码ＩＬ－２前导肽和ＩＬ－２和ＴＮＦ－α成熟肽的序列。重组载体用Ｌｉｐｏｆｅｃｔｉｎ方法引入病毒包装细胞ＰＡ３１７，挑选Ｇ４１８抗性克隆，用ＮＩＨ３Ｔ３细胞测定病毒滴度，获得一滴度为１×１０￣４ＣＦＵ／ｍｌ的高滴度克隆。超速离心浓缩这一重组病毒上清，转导人卵巢癌细胞系ＳＫＯＶ３，经Ｇ４１８筛选获得抗性克隆。ＰＣＲ可从融合基因转导的细胞ＤＮＡ中扩增出１．１ｋｂ的融合基因片断，证明目的基因完整的整合在细胞的基因组ＤＮＡ中，测其上清中的ＩＬ－２和ＴＮＦ－α活性结果显示：ＩＬ－２的活性为８－１５Ｕ／１０￣６ｃｅｌｌｓ／２４ｈ，ＴＮＦ－α的活性为１５０－４００Ｕ／１０￣６ｃｅｌｌｓ／２４ｈ。这一结果表明逆转录病毒介导的融合基因可以在卵巢癌细胞中获得有效表达，表达的融合基因产物在体内和体外部对肿瘤细胞的生长具有抑制作用。     

IL－6和TNF对白血病细胞的调控作用及意义

通过诱导急性白血病肿瘤细胞自分泌白细胞介素６和肿瘤坏死因子，利用急性白血病原代肿瘤细胞和肿瘤细胞系ＨＬ－６０和Ｋ５６２，分别观察了ＩＬ－６和ＴＮＦα对急性白血病细胞的调控作用。结果发现，急性白血病细胞存在着ＩＬ－６和ＴＮＦα的自分泌作用，而ＴＮＦα和ＩＬ－６对白血病细胞则有诱导分化作用；进一步研究发现，ＴＮＦα对急性白血病细胞株还可呈现生长抑制作用；而ＩＬ－６则可表现为生长促进作用。ＩＬ－６和ＴＮＦα对急性白血病细胞的这种凋控在白血病的发病和免疫调控治疗中将有意义。     

枸杞子水提取物对白细胞介素6和肿瘤坏死因子产生的影响

研究了枸杞子水提取物（ＬＢｒ）对全血培养细胞白细胞介素６（ＩＬ－６）和肿瘤坏死因子（ＴＮＦ）产生的影响。结果表明，ＬＢｒ单独不能诱导ＴＮＦ产生，ＬＢｒ０．５μｇ／ｍｌ可明显促进ＬＰＳ诱导的ＴＮＦ产生，但ＬＢｒ１０μｇ／ｍｌ则对ＬＰＳ诱导的ＴＮＦ产生无明显作用ｉＬＢｒ０．５μｙ／ｍｌ不仅可促进ＬＰＳ诱导的ＩＬ－６产生，单独亦可诱导ＩＬ－６产生，但ＬＢｒ１０μｇ／ｍｌ则对ＩＬ－６的产生无明显调节作用。     

IL－6和TNF对白血病细胞的调控作用及意义

通过诱导急性白血病肿瘤细胞自分泌白细胞介素６和肿瘤坏死因子，利用急性白血病原代肿瘤细胞和肿瘤细胞系ＨＬ－６０和Ｋ５６２，分别观察了ＩＬ－６和ＴＮＦα对急性白血病细胞的调控作用。结果发现，急性白血病细胞存在着ＩＬ－６和ＴＮＦα的自分泌作用，而ＴＮＦα和ＩＬ－６对白血病细胞则有诱导分化作用；进一步研究发现，ＴＮＦα对急性白血病细胞株还可呈现生长抑制作用；而ＩＬ－６则可表现为生长促进作用。ＩＬ－６和ＴＮＦα对急性白血病细胞的这种凋控在白血病的发病和免疫调控治疗中将有意义。     

Cleavage of human IgM with human lysosomal elastase

Human lysosomal elastase, a serine proteinase stored in the azurophil granules of polymorphonuclear leucocytes, cleaves human monoclonal IgM producing two fragments and dialyzable peptides. An F(ab)₂μ-like fragment, called IgMe in this report, retains some reactivity with an anti-Fcμ-antiserum and is antigenically deficient with respect to both the subunit (IgMs) produced by reduction and alkylation of IgM and the similar fragment (IgMp) produced by papain digestion. The other fragment is very similar to Fabμ generated by papain digestion, as indicated by immunochemical identity and a similar molecular weight.     

Uptake of human eosinophil peroxidase by human neutrophils.

A cytochemical analysis was carried out for study of the interaction between human eosinophil peroxidase (EPO) and human neutrophils. To this end, neutrophils with a genetic deficiency of myeloperoxidase (MPO) were used to avoid the otherwise inevitable interference of the high endogenous MPO activity of normal neutrophils. The data show that human neutrophils incubated with EPO (1 GU/ml) rapidly bind the enzyme all over the cell surface and internalize it in small vesicles. Part of bound EPO concentrates in a limited area on the cell surface and is then internalized by means of coarse tubular channels. Fusion of the small vesicles to each other or possibly with the tubular channels gives rise ultimately to EPO-containing multivesicular bodies, which, after 30 minutes of incubation, are the only peroxidase-positive structures in the cytoplasm. Under identical experimental conditions, no binding of human MPO to the neutrophils was detected. At concentrations 10 times as high as those used for EPO, a minority of neutrophils bound MPO, but the binding pattern remained diffuse on the plasma membrane and the internalization was negligible. It seems, therefore, that the EPO trapping system of human neutrophils exhibits specificity at least among leukocyte peroxidases. Furthermore, it operates at much lower concentrations of EPO than those reported for EPO uptake by mast cells and basophils. The uptake of EPO by neutrophils may serve to sequester a potentially toxic agent, thus limiting damage to the tissue in eosinophil-rich inflammatory lesions.     

Blastogenic response of human lymphocytes to human cytomegalovirus.

A method was developed for measuring the blastogenic response of human lymphocytes to human cytomegalovirus (CMV). Viral and control antigens were prepared by extracting disrupted infected and uninfected cell cultures with an alkaline buffer. Lymphocytes from ten donors with complement-fixing (CF) antibody exhibited a blastogenic response, whereas cells from ten seronegative donors did not. A relationship between the stimulation index (SI) and the results of neutralization (NT), indirect haemagglutination (IHA) or CF tests was not observed. The maximum blastogenic response occurred after 5 to 7 days of incubation and was usually greater when the cultures were supplemented with homologous plasma instead of sera. The presence of CMV antibody in the supplementary sera did not appear to affect the reactivity of the lymphocytes.     

Effect of recombinant human interferon γ against human cytomegalovirus

Summary Escherichia coli-derived human interferon- (rIFN-) inhibited the replication of human cytomegalovirus (HCMV) synergistically when combined with IFN-. The induction of HCMV DNA polymerase was inhibited in rIFN--treated cells. It is suggested that the induction of 2–5 A synthetase does not play an important role in the anti-HCMV actions of IFNs.With 2 Figures     

The binding of human IgG subclasses to human monocytes

The direct binding of human IgG subclasses to human monocytes has been measured by autoradiography using radiolabeled myeloma proteins. Only IgGl and IgG3 were found to bind strongly to the monocyte surface. This binding could be inhibited both by fresh human serum and by soluble immune complexes.     

Development of human monoclonal antibodies against human cytomegalovirus.

Human monoclonal antibodies (HMAbs) against human cytomegalovirus (HCMV) have been developed by fusion of human spleen cells and human lymphoblastoid cell lines (NP101 and NP197). The cell line NP101 had great advantages in its high fusion frequency and the stability of the resultant hybridomas. The specificity of HMAbs was confirmed by enzyme-linked immunosorbent assay (ELISA) and immunofluorescence staining. Two of the six HMAbs obtained, which were IgG3 subclass, neutralized viral infectivity in the absence of complement. The neutralizing activity of one of these two HMAbs was enhanced in the presence of human complement, whereas the other was not. Another IgG1 subclass HMAb neutralized viral infection only in the presence of complement. The remaining three HMAbs showed no neutralizing activity. Those HMAbs may provide an important approach to studying human immune responses to HCMV. HMAbs having neutralizing activity may prove to be useful for passive immunotherapy of HCMV diseases.     

Persistence of human parvovirus B19 in human tissues

Human parvovirus B19 infection causes various clinical symptoms, such as rash, arthropathy, anemias and fetal death, but it can also remain asymptomatic. The arthropathies and anemias can become chronic for several years, not infrequently resembling autoimmune syndromes. B19 replicates only in red blood cell precursors of bone marrow or fetal liver, resulting in high-titred short-lived viremia, but viral DNA is detectable also in cells of several other types. Recently B19 DNA has been found, by very sensitive amplification tests, in certain tissues not only of symptomatic but also of healthy individuals for several years or decades after B19 infection. The mere presence of B19 DNA in these tissues of a symptomatic patient (e.g. joints in chronic arthritis or skin in dermatomyositis) thereby does not prove that the present disease is caused by B19. The diagnosis has to be verified by other innovative means. How and why viral DNA persists in the tissues of healthy individuals is under investigation.     

Detection of human cytomegalovirus DNA in human tonsillar lymphocytes

The human cytomegalovirus (HCMV) was first isolated in cell cultures from the oropharynx, which is thought to be a site of primary infection. Although HCMV can be recovered from the oropharynx during reactivation phases, its exact site of latency is not known. In the present study we demonstrated evidence suggesting the presence of latent HCMV in this anatomic region--in the palatine tonsils. Samples from 30 tonsils obtained by tonsillectomy were screened for the presence of HCMV. Out of the 30 tonsil donors, 23 were seropositive for HCMV. Three methods were used in attempts to demonstrate HCMV's presence in the tonsils: (1) viral isolation attempts on various cell cultures, (2) immunohistochemical staining--immunoperoxidase method--designed to detect viral antigens, and (3) DNA dot hybridization with a HCMV-DNA probe designed to detect viral DNA. Neither infectious HCMV nor other viruses were isolated in cell cultures. No viral antigens were detected by immunoperoxidase staining in the tonsillar tissue. Four out of the 30 tonsils studied were found to contain viral DNA. In one case in which the tonsillar mononuclear (MN) fraction was separated from the polymorphonuclear (PMN) fraction, only the first fraction contained the viral DNA.     

Immortalization of human keratinocytes with human papilloma virus DNA

Human keratinocytes, derived from the cervix or foreskin, can be immortalized with the HPV-16 or HPV-18 E6 and E7 genes. Two methods of introducing the viral oncogenes into keratinocytes i.e. calcium phosphate transfection and retroviral transduction, are described below, both of which have been optimized for human keratinocytes. While the calcium phosphate transfection method can be used in a normal tissue culture facility, transduction with a retroviral vector containing oncogenes, requires a containment facility and appropriate laboratory practice.