Suppression of the humoral immune response by particulate material extracted from spleen cell subpoulations of MOPC-315 tumor-bearing mice.

Particulate extracts were prepared from MOPC-315 plasmacytoma cells, from whole spleen cells or from splenic macrophages of MOPC-315 tumor-bearing mice. These preparations, when injected into normal mice, inhibited their primary humoral immune response to sheep red blood cells (SRBC). At the same time, particulate extracts from whole spleens or splenic macrophages of normal mice and T cell extracts from spleens of MOPC-315 tumor-bearing mice had no effect on the primary immune response to SRBC. The results suggest that phagocytic spleen cells of tumor-bearing mice contain immunosuppressive particles which originate from the tumor cells.     

Plasmacytoma spleen colonization: a sensitive, quantitative in vivo assay for idiotype-specific immune suppression of MOPC-315.

A spleen colony-forming assay for the measurement of idiotype-specific transplantation resistance to MOPC-315 is described. The assay is highly quantitative, sensitive, reproducible, less time consuming and distinctly superior to conventional in vivo assays which measure tumor incidence, tumor size, and/or host survival time after tumor challenge. The assay directly measures those clonogenic cells of the MOPC-315 myeloma which have a sufficient proliferative capacity to form macroscopic splenic foci within 14 days after intravenous challenge.     

Tumoricidal and immunomodulatory activities of drugs and implications for therapy of mice bearing a late stage MOPC-315 plasmacytoma

The effectiveness of a relatively low dose of cyclophosphamide (15 mg/kg CY), melphalan (2.5 mg/kg L-PAM) or the monofunctional form of CY (150 mg/kg MoCY) for the cure of mice bearing a large primary s.c. MOPC-315 tumor and extensive metastases has been shown to be dependent on the cooperation of the drugs' tumoricidal activity with T-cell-dependent antitumor immunity, the latter facilitated by the drug's immunomodulatory activity. Here, we have compared the curative effectiveness of three additional drugs: methyl nitrosourea (MNU), hydroxyurea (OH-urea) and bis-chloroethyl nitrosourea (BCNU). Among these drugs, only a relatively low dose of BCNU (15-20 mg/kg) was effective in curing most mice (85%) bearing a large, late stage tumor. A higher dose of BCNU (40 mg/kg, LD10) was much less effective. After an optimal dose of BCNU, the proliferative capacity of the tumor cells 24 h after therapy was reduced by greater than 97%. However, viable tumorigenic cells were still present in the primary tumor and enhanced T-cell-dependent antitumor immunity was necessary for their eradication. The cured mice were resistant to tumor rechallenge. When a low curative dose of L-PAM was followed by OH-urea, the therapeutic effectiveness was not affected, but when this dose of L-PAM was followed by a high nontoxic dose of MNU (100-150 mg/kg), the therapeutic effectiveness was diminished even though MNU was highly tumoricidal (i.e. greater than 99% inhibition of proliferative activity). Thus, BCNU appears to be similar to CY, L-PAM and MoCY in its mechanism of MOPC-315 tumor eradication. The alkylating activity of CY, L-PAM, MoCY and BCNU appears to be critical for their combined tumoricidal and immunomodulatory effects. Since BCNU is the simplest of these four drugs with respect to metabolic pathway, a further study with BCNU and related constructs may shed some light on the biochemical mechanisms of their mode of action. At least one reason for the ineffectiveness of OH-urea or MNU at either low or nontoxic high doses was poor tumoricidal or immunomodulatory activity, respectively. Thus, it seems important to consider both the tumoricidal and immunomodulatory activities of drugs when developing regimens for effective chemotherapy.     

Dissociation of natural killer activity and antibody-dependent cellular cytotoxicity in spleen cells of tumor bearing mice

Antibody-dependent cellular cytotoxicity (ADCC) increased with the development of tumors in C3H/He mice bearing spontaneous breast cancer or the syngeneic hepatoma MH-134 and in C57BL/6 mice bearing the syngeneic Lewis lung carcinoma 3LL. This cytotoxicity decreased after treatment with guinea pig, monoclonal IgM anti-Thy 1.2 serum and complement to the non-cancer level thus indicating that the increased ADCC in mice with cancer seems mainly attributable to cells with the Thy 1 antigen. On the other hand, NK activity decreased greatly when mice had tumors. Treatment with monoclonal IgM anti-Thy 1.2 serum and complement showed no significant influence on the natural killer (NK) activity of spleen cells of mice bearing MH-134 cancer, but in the 3LL-bearing mice the activity decreased significantly.     

In vitro spleen leucocyte migration and phytohaemagglutinin-stimulated lymphocyte transformation of immunosuppressed mice cells. II. Cells from mice treated by azathioprine and/or immune stimulation or thymectomy

An in vitro study of the spleen leucocyte migration ability and the phytohaemag-glutinin (PHA) stimulated peripheral lymphocyte response was made on cells derived from mice treated by azathioprine, immune stimulation, or thymectomy and azathioprine. These responses were compared with those shown by normal mice and found to be considerably depressed. Thymectomy combined with azathioprine produced the greatest change which persisted at 40 days. These changes suggested that azathioprine in common with thymectomy, antilymphocyte globulin and radiotherapy produced some of its immunosuppression by depressing T-cell function.     

Determination of dissociation constants and ligand specificity of detergent solubilized surface membrane immunoglobulin a from MOPC-315

Surface membrane immunoglobulin from MOPC-315 plasmacytoma cells (smM315) was isolated by nonionic detergent lysis of radioiodinated cells and affinity chromatography on Dnp-aminohexyl-Sepharose 4B. Verification of the solubilized molecule as an integral membrane protein, distinct from secreted MOPC-315 IgA (M315) was accomplished by NaDodSO^?₄-PAGE, charge-shift electrophoresis and molecular sieve gel filtration with NP-40 and deoxycholate. smM315 was compared to reduced and alkylated monomeric secreted immunoglobulins from MOPC-315, MOPC-460, and XRPC-25 by quantitative affinity chromatography (QAC) using two differently substituted Dnp-aminohexyl-Sepharose 4B resins. Unique patterns of cross-reactivity of all secreted myeloma proteins were independently established with a competitive hapten inhibition assay using ¹²⁵I-Dnp₂₆BSA as the precipitating probe. After derivation with dinitrobenzylsulfonate, Dnp-aminohexyl-Sepharose 4B was modified with succinic anhydride which, with the inclusion of 0.03% Doc in a PBS and 0.1% NP-40 buffer, prevented nonhapten specific protein-matrix interactions during QAC. Dissociation constants determined by QAC for three ligands, (dinitrophenyl-glycine, trinitrophenyl-amino-caproate and tetramethylrhodamine) were essentially the same for smM315 and M315. Both of the other nitrophenyl binding IgA myelomas had distinct and significant differences in dissociation constants. Thus, for a differentiated antibody secreting cell which has undergone a heavy chain class switch, such as MOPC-315, the cell surface immunoglobulin has an identical ligand binding active-site as the secreted immunoglobulin.     

Indomethacin stimulation of macrophage cytostasis against MOPC-315 tumor cells is enhanced by endogenous metabolites of lipoxygenase and counteracted by prostaglandin E2

Conclusions We have shown that indomethacin stimulation of macrophage cytostasis against MOPC-315 tumor cells can be counteracted by PGE₂ and by the lipoxygenase inhibitor NDGA. The results are congruent with the earlier finding, which showed that LTD₄ reinforces the effect of indomethacin on macrophage cytostasis, which thus is modulated by the balance between cyclooxygenase and lipoxygenase metabolites.     

树突状细胞激活的肿瘤浸润淋巴细胞对荷瘤小鼠免疫功能影响的研究

目的:探讨H22细胞全细胞性抗原致敏的DC激活的TIL体外抗小鼠肝癌活性;并将H22细胞全细胞性抗原致敏的DC激活的TIL(H22-DC-TIL)过继免疫荷瘤小鼠,研究其对荷瘤小鼠免疫功能的影响。方法:从小鼠四肢长骨骨髓中获取DC,应用粒/巨噬细胞集落刺激因子(GM-CSF)、白介素-4(IL-4)和肿瘤全细胞性抗原致敏DC,然后用DC激活TIL,观察TIL在体外对H22细胞、Hepal-6细胞和B16细胞的杀伤活性;检测应用H22-DC-TIL后荷瘤小鼠的脾淋巴细胞的NK、LAK、CTL活性及血清TNF活性,并与对照组相比较。结果:(1)H22-DC-TIL具有很强的对H22细胞杀伤活性(杀伤率为71.31%±3.11%),明显高于其对Hepal-6和B16细胞的杀伤活性(杀伤率分别为50.11%±3.03%和30.31%±2.89%);也明显高于未经DC激活的TIL、H22-DC-小鼠脾淋巴细胞和未经DC激活的小鼠脾淋巴细胞对H22细胞杀伤活性(杀伤率分别为49.80%±3.21%、48.76%±3.60%和19.23%±2.71%)和对Hepal-6细胞杀伤活性(杀伤率分别为39.40%±3.21%、38.62%±2.87%和18.73%±2.40%)以及对B16细胞杀伤活性(杀伤率分别为26.38%±2.51%、25.82%±2.70%和18.34%±3.01%),同时B16-DC-TIL(TIL来源于H22瘤体)也可诱导相对较低的对B16细胞的特异性细胞杀伤活性。(2)H22-DC-TIL可明显诱导提高荷瘤小鼠脾淋巴细胞NK、LAK和CTL活性(活性分别为30.43%±1.35%、31.40%±1.80%和35.30%±1.20%),并可检测到血清TNF水平明显上升[血清TNF为(40.41±1.85)U/m l],它们均达正常对照组水平,与未经DC激活的TIL组、H22-DC-小鼠脾淋巴细胞组、未经DC激活的小鼠脾淋巴细胞组、生理盐水组分别对应比较,差异均有显著性(P<0.01)。结论:(1)H22-DC-TIL可产生很强的体外针对H22细胞的特异性杀伤活性。(2)H22-DC-TIL可明显诱导提高荷瘤小鼠特异性抗肿瘤免疫反应。     

Active suppression masks an underlying enhancement of antibody production in vitro by spleen cells from BCG-infected mice.

The depressed antibody responses resulting from the administration of live BCG i.v. to mice have been investigated. The antibody response of spleen cells to SRBC or DNP-Ficoll in vitro was followed using Marbrook culture vessels. Depressed responses were also found in vivo confirming the results obtained in vitro. The response in vitro of normal spleen cells was suppressed by the addition of spleen cells from mice injected with BCG but not by the medium in which they had been growing for 2 days. The response of the normal spleen cells was also not suppressed by freeze/thaw disrupted BCG spleen cells, suggesting that the depressed responses in the mice injected with BCG are due to an active suppression by intact cells. This was confirmed by the cell-depletion experiments. Removal of cells from the BCG-primed cell populations using carbonyl iron or adherence to plastic not only abrogated the depressed responses but revealed an underlying enhancement of the immune response. The data suggest that the suppressive cell might be a macrophage.     

Anomalous reactivity of anti-T cell sera on spleen cells from T-cell-deprived mice and on mitogen-stimulated nude mice spleen cells

Recent results have shown that various alloantisera which react in the expected fashion on lymphocyte populations can react anomalously against cultured tumor cell populations because of the presence of contaminating antibodies against murine leukemia virus (MLV) antigens. Since it is now known that activation of MLV can occur in certain types of dividing lymphocyte populations, anti-T cell sera were tested on lymphoid cell populations in which T cells were absent or greatly reduced in numbers, but where activation of MLV in the B cell population would be expected. Whereas normal, freshly harvested, nude mice spleen cells were unreactive, in vitro:stimulation of these cells with the B cell mitogen, lipopolysaccharide, led to a high degree of sensitivity to the cytotoxic effects of anti-T alloantisera or heteroantisera. Spleen cells from adult thymectomized, lethally-irradiated, bone marrow-reconstituted mice also showed unexpected reactivity with the anti-T cell sera. In both cases, reactivity was noted only if absorbed rabbit serum was used as a complement source in the cytotoxic assays. The anomalous anti-B cell activity of the anti-T cell sera could be removed by absorption with relatively small numbers of cells from Thy-negative cultured tumor cell lines, including fibrosarcomas, but not by absorption with thymocytes. Hence, activated or stimulated B cells may react strongly with allo-or hetero- anti-T cell sera under certain conditions, and this anomalous reactivity appears unrelated to the presence of the anti-T cell antibodies in the sera.     

抗原基因修饰的树突状细胞诱导机体产生特异性免疫应答的实验研究

目的：探讨腺病毒介导的肿瘤抗原基因修饰的树突状细胞（ＤＣ） 体内免疫后对抗原特异性抗肿瘤免疫反应的诱导作用。方法：以βｇａｌ 为模拟抗原,以转染有ＬａｃＺ基因并稳定表达βｇａｌ 的淋巴瘤细胞Ｅ２２ 为肿瘤细胞模型,用携带编码βｇａｌ的ＬａｃＺ基因的重组腺病毒载体（ＡｄＬａｃＺ） 转染小鼠骨髓ＤＣ,检测转染的效率及ＬａｃＺ基因修饰ＤＣ刺激Ｔ细胞增殖的能力,观察皮下免疫ＬａｃＺ基因修饰ＤＣ后小鼠引流区淋巴结细胞数量和组分的变化以及诱导产生ＣＴＬ和抵抗Ｅ２２ 细胞再攻击的能力。结果：ＬａｃＺ基因修饰后２４ 、４８ 、７２ ｈ,均能检测到８０％ 以上的ＤＣ表达βｇａｌ,此基因修饰的ＤＣ可有效刺激同基因型小鼠脾脏Ｔ淋巴细胞增殖反应;将其皮下免疫小鼠１ ｗ 后再接种Ｅ２２ 细胞,小鼠的存活期较其他ＤＣ免疫小鼠显著延长,但对Ｂ１６ 黑色素瘤细胞的攻击无免疫保护作用。此外,ＬａｃＺ基因修饰的ＤＣ免疫小鼠的引流淋巴结细胞数量显著增加,且产生了针对Ｅ２２ 的而非ＥＬ４ 或Ｂ１６ 的特异性ＣＴＬ。结论：腺病毒介导的肿瘤抗原基因修饰的ＤＣ能有效诱导机体产生特异的抗肿瘤免疫反应。     

In vitro immune response of spleen cells from mice genetically selected for high or low antibody production.

The aim of this study was the identification of the cell type in which genes selected for high or low response to SRBC express their functions. Spleen cells from high (H) and low (L) responder mice were immunized with SRBC in the Mishell and Dutton system. An antibody response of different magnitude was found in cultures of H and L spleen cells, the difference being at least as great as that observed in vivo. This finding under experimental conditions allowing the exclusion of any influence of the animal milieu during the immune response, suggest macrophages, B, and T lymphocytes as possible target cells of gene action. In vitro cell separation and recombination experiments in which spleen cells were immunized with SRBC, TNP-LPS, or TNP-HRBC indicate that the genetic differences between H and L responders brought about by selective breeding are expressed in lymphocytes to greater extent than in macrophages. The role of histoincompatibility in the recombination experiments in unlikely but cannot be excluded. Among lymphocytes, B cells but not helper T cells were found more responsive in cultures of spleen cells from H than from L mice.     

In vitro responses of spleen cells from Trichinella spiralis-infected mice

The in vitro cellular immune responses of spleen cells from mice infected with Trichinella spiralis and immunized with BCG have been investigated. ICR/CD-1 mice were originally infected with 200 T. spiralis larvae 22 days prior to infection with 4 X 10(6) viable or heat-killed mycobacteria. Analysis of the splenic cell populations indicated that significant increases in adherent cells (macrophages) were noted only in groups previously infected with the nematode; the concentration of non-adherent cells (lymphocytes) did not vary insignificantly among any of the experimental groups. Assay of blast cell transformation and 3H-thymidine incorporation demonstrated the ability of T. spiralis infection to potentiate in vitro cellular immune reactions. These findings support earlier in vivo studies concerning nematode-induced immunopotentiation of delayed-type hypersensitivity reactions, and provide additional evidence that infection with this nematode enhances the immune capabilities of both stimulated lymphocytes and nonspecific phagocytic cells.