Two tumor models of curative adoptive chemoimmunotherapy using tumor-infiltrated spleen cells with potent antitumor cytotoxicity stimulated by antigen-sharing tumors

Previously we have established curative protocols for adoptive chemoimmunotherapy (ACIT) of mice bearing different plasmacytomas that are known to bear cross-reacting antigens: (a) the cure of mice bearing an early-stage, nonpalpable MOPC-315 tumor by a very low dose of cyclophosphamide (10 mg/kg) and cultured MOPC-315-tumor-infiltrated (TI) spleen cells (25×10⁶) and (b) the cure of mice bearing a late-stage, relatively drug-resistant, highly metastatic RPC-5 tumor with cyclophosphamide (100 mg/kg) and cultured RPC-5 TI spleen cells (25×10⁶–50×10⁶). In both models, the spleen cells were obtained from mice bearing a late-stage tumor and were cultured for 5 days in the presence of polyethyleneglycol 6000 and autochthonous tumor cells as a source of tumor antigen. Here we show that RPC-5 tumor cells could substitute for MOPC-315 tumor cells in the 5-day culture of MOPC-315 TI spleen cells so that they became curative in ACIT for mice bearing an early-stage MOPC-315 tumor. Similarly, MOPC-315 tumor cells could substitute for RPC-5 tumor cells in the 5-day culture of RPC-5 TI spleen cells so that they became curative in ACIT of mice bearing a late-stage RPC-5 tumor. In addition, RPC-5 TI spleen cells cultured with either MOPC-315 or RPC-5 tumor cells were effective in curing all mice bearing an early-stage MOPC-315 tumor by ACIT. However, MOPC-315 TI spleen cells whether cultured with MOPC-315 or RPC-5 tumor cells, were much less effective than cultured RPC-5 TI spleen cells in curing mice bearing a late-stage RPC-5 tumor by ACIT (although the survival of these mice was extended significantly). Interestingly, whereas RPC-5 TI spleen cells cultured with either MOPC-315 or RPC-5 tumor cells were as effective as MOPC-315 TI spleen cells cultured under the same conditions in lysing MOPC-315 tumor cells in vitro, MOPC-315 TI spleen cells that had been cultured with either MOPC-315 or RPC-5 tumor cells exerted a much weaker in vitro cytotoxic T lymphocyte activity against RPC-5 tumor cells than did RPC-5 TI spleen cells that had been cultured under the same conditions.Work was supported by research grant CA-30088 from the National Cancer Institute and IM-435 from the American Cancer Society. M. B. M. was supported by Career Development Award CA-01350 from the National Cancer InstituteThis work is in partial fulfillment of the requirements for the Ph. D. degree     

Soluble Sema4D cleaved from osteoclast precursors by TACE suppresses osteoblastogenesis

Bone remodelling is mediated by orchestrated communication between osteoclasts and osteoblasts which, in part, is regulated by coupling and anti-coupling factors. Amongst formally known anti-coupling factors, Semaphorin 4D (Sema4D), produced by osteoclasts, plays a key role in downmodulating osteoblastogenesis. Sema4D is produced in both membrane-bound and soluble forms; however, the mechanism responsible for producing sSema4D from osteoclasts is unknown. Sema4D, TACE and MT1-MMP are all expressed on the surface of RANKL-primed osteoclast precursors. However, only Sema4D and TACE were colocalized, not Sema4D and MT1-MMP. When TACE and MT1-MMP were either chemically inhibited or suppressed by siRNA, TACE was found to be more engaged in shedding Sema4D. Anti-TACE-mAb inhibited sSema4D release from osteoclast precursors by ~90%. Supernatant collected from osteoclast precursors (OC-sup) suppressed osteoblastogenesis from MC3T3-E1 cells, as measured by alkaline phosphatase activity, but OC-sup harvested from the osteoclast precursors treated with anti-TACE-mAb restored osteoblastogenesis activity in a manner that compensates for diminished sSema4D. Finally, systemic administration of anti-TACE-mAb downregulated the generation of sSema4D in the mouse model of critical-sized bone defect, whereas local injection of recombinant sSema4D to anti-TACE-mAb-treated defect upregulated local osteoblastogenesis. Therefore, a novel pathway is proposed whereby TACE-mediated shedding of Sema4D expressed on the osteoclast precursors generates functionally active sSema4D to suppress osteoblastogenesis.     

p62蛋白的分子功能及其在疾病中的研究进展

螯合体1(SQSTM1/p62)是一种选择性自噬接头蛋白,在清除待降解蛋白、维持细胞内蛋白质稳态中发挥重要的调控作用。p62蛋白具有多个功能结构域,介导与多种蛋白质发生相互作用进而精确调节特定的信号通路,从而将p62蛋白与氧化防御系统、炎症反应和营养感知等重要生命过程联系起来。研究表明p62的突变或者表达异常与多种疾病的发生发展过程密切相关,包括神经退行性疾病、肿瘤、感染性疾病、遗传性疾病以及慢性疾病等。本文综述了p62蛋白的结构特征、分子功能,并系统介绍其在蛋白质稳态和信号通路调控中的多种功能,总结了p62在疾病发生发展中的复杂性与多面性,以期为p62蛋白的功能与相关疾病研究提供参考。     

基于碳酸酐酶IX的肿瘤成像和治疗研究进展

碳酸酐酶IX (carbonic anhydrase IX, CAIX)是一种在乏氧肿瘤细胞表面特异性过表达的跨膜蛋白,具有调节肿瘤细胞内外酸碱度的功能,与肿瘤增殖、侵袭和转移息息相关。因此,CAIX是一个很有潜力的肿瘤成像和治疗靶点。本文详细阐述了基于CAIX的肿瘤成像、治疗和诊疗一体化的研究进展,并对CAIX作为抗肿瘤靶点的应用前景进行了展望。     

Cytoskeleton modifications induced by phenobarbital, 2-acetylaminofluorene and 4-acetylaminofluorene in normal and initiated/selected hepatocytes: Relation with the “resistant” phenotype

Initiatedlselected (ISH) and normal (NH) rat hepatocytes were used to study cytoskeleton modifications induced by three liver acting chemicals: 2-AAF, a liver complete carcinogen; PB, a liver tumor promoter; and 4-AAF, a noncarcinogen analogue of 2-AAF. Cytoskeleton alterations were visualized by disappearance of F-actin fibers and tubulin depolymerization. The three drugs induced actin fragmentation in normal hepatocytes; a net loss of actin protein was observed with PB. They also induced varied tubulin depolymerization. The principal difference between chemicals is that 2-AAF led to non-reversible effects, in comparison with PB and 4-AAF which induced reversible damages on cytoskeleton. By contrast to normal hepatocytes, the cytoskeleton of ISH obtained from rats subjected to the resistant hepatocyte protocol was much less susceptible to the effect of the three chemicals. Moreover, we observed a lack of LDH release in the culture medium and a very rapid inducibility of GST activity after exposure of ISH to drugs. The moderate effect of the three chemicals on actin and tubdin in ISH could thus be explained by the resistant metabolic profile of these cells.Abbreviations TPA 12-O-tetradecanoyl-phorbol-13-acetate - PB phenobarbital - 2-AAF 2-acetylaminofluorene - 4-AAF 4-acetylaminofluorene - GSH reduced glutathione - GST glutathione-S-transferase - LDH lactatedehydrogenase - NH normal hepatocytes - ISH initiated/selected hepatocytes - BSA bovine serum albumin     

Crystallization and preliminary X-ray analysis of nonglycosylated tissue inhibitor of metalloproteinases-1, N30QN78Q TIMP-1

A nonglycosylated (N₃₀QN₇₈Q) form of the human tissue inhibitor of metalloproteinases, TIMP-1, has been prepared and crystallized in a form suitable for X-ray diffraction analysis. Small single crystals have been grown using sodium tartrate as a precipitant. The crystals are in space group P2₁, with cell dimensions a = 35.28, b = 53.95, c = 48.56, and β = 96.0°. There is a single molecule of TIMP-1 in the asymmetric unit. The crystals diffract to at least 2.3 Å resolution. Complete data have been collected to 2.9 Å and a search for heavymetal derivatives is in progress. © 1993 Wiley-Liss, Inc.     

Elevated serum α-fetoprotein level of nude mice bearing hepatoma cells by treatment with monoclonal antibodies to α-fetoprotein

This study was carried out to clarify the reason for elevation of serum α-fetoprotein (AFP) level of nude mice bearing hepatoma cells after treatment with monoclonal antibodies (MoAbs) to AFP. MoAbs to AFP showed no effect on the cumulative amounts of AFP secreted from human hepatoma cell line, HuH-7, in vitro. However, the treatment of nude mice bearing HuH-7N cells (HuH-7 xenograft) with MoAbs to AFP led to elevation of the serum AFP level in spite of the fact that the growth curve of HuH-7N cells was similar to that for PBS treatment. This apparent elevation of the serum AFP level is thought to be due to the slow elimination of AFP-MoAb immune complexes with little lattice structure from circulation, but not the enhancement of AFP secretion of HuH-7N cells. Thus, when using a MoAb alone or MoAb-drug conjugate, the serum AFP level should only be cautiously used as a tumor marker for evaluating the targeting immunotherapy.     

The synergistic effects of interleukin 2 and interleukin 7 on the proliferation and autologous tumor cell lysis of tumor-associated lymphocytes

Interleukin-7 (IL-7) has an ability to stimulate the proliferation of pre-B cells. It has been shown that IL-7 can also activate T lymphocytes. We here demonstrate that IL-7 in combination with interleukin-2 (IL-2) can drive cell proliferation and enhance the autologous tumor cell lysis by peripheral blood mononuclear cells (PBMC) and autologous mixed lymphocyte tumor cell culture (MLTC)-derived effector cells (MLTC cells). These synergistic effects of IL-2 and IL-7 on the proliferation and the augmentation of autologous tumor cell lysis were found for both effector cells. These effects were inhibited by neutralizing antibodies to IL-2 or IL-7, and by a combination of both antibodies, significantly. In terms of phenotypical expression, CD3 positive cells comprised the vast majority of MLTC cells after culture in medium containing IL-2 and IL-7 with an increase of IL-2 receptor positive cells.Abbreviations CD cluster differentiation - IFN interferon - IL interleukin - JRU Japanese Reference Unit - LAK lymphokine activated killer - mAb monoclonal antibody - MLTC mixed lymphocyte tumor cell culture - PBMC peripheral blood mononuclear cells - TILs tumor infiltrating lymphocytes     

嵌合抗原受体T细胞治疗的现状与展望

肿瘤严重威胁着人类健康,当前肿瘤传统的治疗方法有手术治疗、化疗、放疗和靶向药物治疗等。近年来,肿瘤免疫治疗,尤其是嵌合抗原受体（chimeric antigen receptor,CAR） T细胞免疫疗法在基础研究与临床应用中蓬勃发展,并在治疗血液系统恶性肿瘤方面取得了巨大成功。然而,大量研究显示,细胞免疫治疗后可出现不同程度的毒副反应,且部分患者缓解后再次复发。因此,了解细胞治疗面临的挑战与局限性,寻找解决的办法,对继续发挥细胞免疫疗法的潜能具有重要意义。本文就免疫细胞的CAR结构、病毒载体的选择、细胞治疗面临的挑战及前景进行综述。     

人胎肝细胞分泌的低分子抑瘤物对白血病细胞的抑制作用

本工作证明了在胎儿组织中存在一类低分子天然肿瘤抑制物,它是胎儿组织细胞生成和分泌的,对瘤株细胞和原代白血病细胞有选择性抑制作用。初发期或复发期急性非淋巴细胞白血病患者的骨髓在体外液体培养条件下与肝细胞上清及其甲醇提取物共同孵育4d,可使所有病例的骨髓AML—CFU降低到不可检出的程度。因而,低分子天然抑瘤物是天然肿瘤免疫中的一个组成部分,它在肿瘤的诊断和治疗中有着深远的意义。