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Summary The possible relation between the site of primary intracranial tumors and mitogenic responses of blood lymphocytes was analyzed in 115 patients who had not undergone surgery or received any radiation or chemotherapy. Some of the patients had however received corticosteroid treatment. PHA responses were impaired in nonsteroid treated patients with tumors affecting the left cerebral hemisphere. They were normal in patients with tumors affecting the right cerebral hemisphere or central structures of the brain or tumors growing in the posterior fossa of the skull. Lymphocyte responses to PPD were normal in patients with hemispheric or posterior fossa tumors. However, the PPD response was sharply reduced in patients with central tumors. The results could not be explained by different histological tumor types or anticonvulsant medication in the various patient groups. In addition, the capacity of sera to promote mitogen stimulation of lymphocytes did not differ significantly between the patient groups. It is speculated that intracranial tumors may interfere with the function of certain centers in the brain which are involved in the regulation of lymphocyte responses.  相似文献   

3.
We have previously demonstrated that patients with primary malignant brain tumors have impaired in vivo and in vitro cell-mediated immunity. The purpose of the present research was to employ pokeweed mitogen (PWM)-induced secretion of immunoglobulin (Ig) by peripheral blood lymphocytes (PBL) to further investigate impaired lymphocyte function in these patients. The PWM response of PBL from normal individuals averaged 8384 plaque-forming cells (PFC) per 10(6) cells, whereas the response of PBL from patients averaged 1590 PFC/10(6). The decreased PWM response of PBL patients could not be improved by varying the number of PBL placed in culture or employing different concentrations of PWM. Co-culture experiments to detect the presence of suppressor cells in PBL and purified T cell preparations from patients demonstrated that enhanced suppressor cell activity was not evident. Next, experiments were performed to assess the T-helper cell activity present in purified T cell preparations obtained from patients. The results demonstrated that T cells from patients lacked the ability to provide adequate helper activity in the PWM response. Moreover, studies with monoclonal antibodies directed against T cell subsets revealed that PBL from patients have a reduced percentage of T-helper cells (40%) as compared with normal values (55%). In concert with T-helper cell anomalies, B cell function in these patients also is diminished. Thus, these observations indicate that a combined T-helper and B cell defect may contribute to the broad impairment of host immunocompetence observed in patients with primary gliomas.  相似文献   

4.
Tissue specimens from 105 human gliomas and 57 human meningiomas were obtained at surgery, dissociated into single cells and small cell aggregates and then plated onto plain plastic tissue culture dishes and dishes which had been precoated with an extracellular matrix (ECM) derived from bovine corneal endothelium. In 80% of the glioma cases we observed a marked improvement in initial plating efficiency, colony formation and speed of attachment when cells were plated on ECM. In 5 cases cells attached only to the ECM-coated dishes but remained afloat in the untreated dishes. In addition it could be noted that over the first 2 days, those cells which had been initiated on ECM showed more signs of morphological differentiation, i.e., extension of cytoplasmic processes or formation of fiber networks between cell groups. If adaptation occurred and proliferation began in vitro, either immediately or after a several days' lag phase, both the ECM-cultured cells as well as those which slowly had adapted to culture on plastic could be passed on to untreated culture ware and perpetuated thereon. In the case of well-differentiated low-grade gliomas where no growth in culture took place, the cultures on ECM could at least be used for initial experiments in the primary cultures (P0). Meningiomas usually attached well to both, plastic or ECM. In 50% of our cases the plating efficiency was higher on ECM but after successful initial culture, the delay until the cells on plastic reached confluence in comparison with those on ECM was 1 or 2 days. Again there were 2 cases in which the cells would not plate on plastic. Here the cells which after 1 day were still afloat plated to more than 80% within the first 2 h after transfer to ECM. In all cases the cells from plastic and ECM cultures were indistinguishable and could be passed onto untreated dishes henceforth. In later culture stages ECM offers several advantages: It is easier to shift cells to serum-free defined culture conditions, the cells will grow at a faster rate on ECM when in higher passages and the maximal number of passages possible is higher on ECM.  相似文献   

5.
The TCR complex signals through a set of 10 intracytoplasmic motifs, termed immunoreceptor tyrosine-based activation motifs (ITAMs), contained within the gamma-, delta-, epsilon-, and zeta-chains. The need for this number of ITAMs is uncertain. Limited and contradictory studies have examined the ability of subsets of the TCR's ITAMs to signal into postthymic primary T lymphocytes. To study signaling by a restricted set of ITAMs, we expressed in transgenic mice a chimeric construct containing the IAs class II MHC extracellular and transmembrane domains linked to the cytoplasmic domain of the TCR zeta-chain. Tyrosine phosphorylation and receptor cocapping studies indicate that this chimeric receptor signals T cells independently of the remainder of the TCR. We show that CD4+ and CD8+ primary T cells, as well as naive and memory T cells, are fully responsive to stimulation through the IAs-zeta receptor. Further, IAs-zeta stimulation can induce primary T cell differentiation into CTL, Th1, and Th2 type cells. These results show that the zeta-chain ITAMs, in the absence of the gamma, delta, and epsilon ITAMs, are sufficient for the activation and functional maturation of primary T lymphocytes. It also supports the isolated use of the zeta-chain ITAMs in the development of surrogate TCRs for therapeutic purposes.  相似文献   

6.
Summary Immunological studies for evaluation of cellular immunity were carried out on 22 patients who had two primary malignant tumors and who had no evidence of active disease. The tests performed were for skin reactivity to 3 recall antigens, PPD, Candidine, and Streptokinase and in vitro lymphocyte stimulation by PHA. Of these, 6 patients were anergic to all three recall antigens and 5 other patients to two out of three antigens. A depression of the in vitro reactivity was encountered in 11 patients. The immune incompetence was more evident in patients with simultaneous tumors than in those with metachroneous tumors. The longer the interval between the appearance of the primary and the secondary tumors, the less immunosuppression was seen.Presented at the 24th Israel Medical Association Conference on Immunological Aspects of Cancer, Tel-Aviv, December 26, 1974This work was supported in part by the Office of the Administrator General, Ministry of Justice and the Medical Research Fund under the Sponsorship of the Ministry of Health  相似文献   

7.
BackgroundIn photosynthetic organisms, transketolase (TK) is involved in the Calvin-Benson cycle and participates to the regeneration of ribulose-5-phosphate. Previous studies demonstrated that TK catalysis is strictly dependent on thiamine pyrophosphate (TPP) and divalent ions such as Mg2 +.MethodsTK from the unicellular green alga Chlamydomonas reinhardtii (CrTK) was recombinantly produced and purified to homogeneity. Biochemical properties of the CrTK enzyme were delineated by activity assays and its structural features determined by CD analysis and X-ray crystallography.ResultsCrTK is homodimeric and its catalysis depends on the reconstitution of the holo-enzyme in the presence of both TPP and Mg2 +. Activity measurements and CD analysis revealed that the formation of fully active holo-CrTK is Mg2 +-dependent and proceeds with a slow kinetics. The 3D–structure of CrTK without cofactors (CrTKapo) shows that two portions of the active site are flexible and disordered while they adopt an ordered conformation in the holo-form. Oxidative treatments revealed that Mg2 + participates in the redox control of CrTK by changing its propensity to be inactivated by oxidation. Indeed, the activity of holo-form is unaffected by oxidation whereas CrTK in the apo-form or reconstituted with the sole TPP show a strong sensitivity to oxidative inactivation.ConclusionThese evidences indicate that Mg2 + is fundamental to allow gradual conformational arrangements suited for optimal catalysis. Moreover, Mg2 + is involved in the control of redox sensitivity of CrTK.General significanceThe importance of Mg2 + in the functionality and redox sensitivity of CrTK is correlated to light-dependent fluctuations of Mg2 + in chloroplasts.  相似文献   

8.
In these studies, the role of glycosylphosphatidylinositol (GPI)-anchored surface molecules during T cell activation was investigated in fresh T cells and T cell lines obtained from patients with paroxysmal nocturnal hemoglobinuria. For control, GPI-expressing T cells of the same patients were used. Unstimulated GPI- T cells exhibited significantly reduced surface expression of the activation Ag CD45R0, compared with GPI+ T cells. In addition, in measurements of proliferation, IFN-gamma production, and induction of second messengers such as cytoplasmic Ca2+, CD48- lymphocytes showed a similar response to TCR-specific stimulation, compared with CD48+ lymphocytes. In contrast, stimulation with the lectin PHA produced a decreased response of CD48- lymphocytes in these functions. In addition, stimulation with cross-linked CD59 mAb increased the proliferation of GPI-molecule expressing CD48+ T cell lines only. From these data, it can be concluded that GPI-anchored surface molecules play an important role in T lymphocyte activation.  相似文献   

9.
Multiple primary malignant tumors have been documented with increased frequency over the last two decades. Continuously increasing success of modern oncotherapy has led to long-term remissions in many cases, but this success rate poses a growing risk for the development of second primary malignancies. The incidence of those involving an intraocular tumor is relatively rare. In the present study we report five ocular melanoma patients with second primary malignant tumors diagnosed during a fourteen-year period in our department. We wish to emphasize that an intraocular mass lesion in a patient with a history of a previous malignancy should not be dismissed as a metastatic lesion. The diagnosis of an intraocular lesion as a separate primary tumor drastically changes the prognosis and the therapeutic approach.  相似文献   

10.
A investigation was undertaken to measure the presence of trace elements in some intracranial tumors using the instrumental neutron activation analysis technique. The following 20 minor and trace elements were investigated: Na, Mg, Al, P, Cl, K, Ca, Cr, Mn, Fe, Co, Cu, Zn, As, Se, Br, Rb, Sb, I, and Cs. Our results are compared with other trace element analyses in human brain tissue.  相似文献   

11.
The response after gamma-irradiation of lymphocytes from 8 patients with Alzheimer's disease (AD), 3 patients with Huntington's disease and 13 normal subjects to stimulation by phytohaemagglutinin (PHA) was assayed by incorporation of [3H]thymidine. The response of non-irradiated cells was found to be significantly lower in AD cells than in age-matched normals but not significantly lower in old normals than in young normals. However, the response of irradiated cells to PHA, expressed as a percentage of that in non-irradiated cells, was found to be similar in AD patients, young and old normals and in HD patients.  相似文献   

12.
In various mammalian cell types the stimulation of the plasma membrane amiloride-sensitive Na+/H+ exchange and the resulting increase of intracellular pH (pHi) play a key role in the initiation of cell proliferation. In the present work we have investigated whether Na+/H+ exchange is involved in normal human B cell proliferation and whether it is also operating in malignant B-chronic lymphocytic leukemia (B-CLL) lymphocytes. Our results show that: 1) normal human B cells contain an operating Na+/H+ exchanger, as inferred by their ability to recover pHi after acid-loading in a HCO3- -free medium and by evidences that LPS and phorbol ester PMA elicit a pHi rise inhibitable by either 5-(N-ethyl-N-isopropyl)amiloride (EIPA) or a Na+-free medium; 2) LPS-induced proliferation of normal human B cells is strongly inhibited when the amiloride analog EIPA (5 microM) is present in the culture medium (after 72 h the proportion of B cells incorporation bromodeoxyuridine falls from 13.9 +/- 3.9% to 2.8 +/- 1.1%); 3) EIPA does not affect BdR incorporation when B cells proliferation is induced by the co-mitogenic activity of IL-4 and low m.w. B cell growth factor (BCGF); 4) B-CLL cells, which proliferate in response to IL-4/BCGF but not to LPS, fail to increase pHi above their pHi resting levels when challenged with LPS or PMA and pHi recovery after acid-loading is highly impaired. These results lead to conclude that Na+/H+ exchange operation is necessary for LPS-(but not for IL-4/BCGF)-induced proliferation of human normal B lymphocytes and that Na+/H+ exchange activation is impaired in malignant B-CLL lymphocytes.  相似文献   

13.
Oh JE  Krapfenbauer K  Lubec G 《Amino acids》2004,27(2):141-147
Summary. The advent of proteomics has provided a tool for the concomitant identification and determination of a large series of proteins using two-dimensional gel electrophoresis with subsequent mass spectrometrical analysis. We tried an approach to analyse the high abundance enzyme proteome of a lymphocytic cell line.Immortalised lymphocytes were grown in RPMI 1640 in the presence of glutamine, harvested and the 100,000×g supernatant of the homogenate was applied on two-dimensional gel electrophoresis with subsequent in-gel digestion of protein spots and MALDI-TOF (Matrix-associated laser desorption/ionization mass spectroscopy) analysis of resulting peptides using specific software.A series of 57 metabolic enzymes were identified including enzymes of carbohydrate, amino acid, purine and intermediary metabolism.We are presenting a tool for the analysis of metabolic systems including enzyme deficiencies at the protein level with the advantage of unambiguous identification of proteins and thus complementing enzyme activity determinations.J. E. Oh and K. Krapfenbauer have been equally contributing to the work.  相似文献   

14.
 It has been reported that the in vitro development of tumoricidal function in alveolar macrophages from lung cancer patients is reduced significantly when compared to that in peripheral blood monocytes from the same patients or alveolar macrophages from control patients. In the present investigation, a method for potentiating the development of tumoricidal function in alveolar macrophages from lung cancer patients is described. This method, which relies on priming the macrophages with purified, allogeneic peripheral blood lymphocytes from normal donors, could not be demonstrated when autologous lymphocytes from lung cancer patients were used in the priming coculture. The augmentation of tumoricidal function appears to be mediated by one or more soluble factors, since supernatants from cocultures of alveolar macrophages and allogeneic peripheral blood lymphocytes could enhance the cytotoxic function of freshly obtained alveolar macrophages. Furthermore, it appears that NK cells are necessary for this effect, since depletion of CD56+/CD57+ cells from allogeneic lymphocytes eliminated their capacity to enhance alveolar macrophage cytotoxic function. The augmentation of cytotoxic function elicited in alveolar macrophages by this method was not associated with changes in the secretion of tumor necrosis factor α, or interleukin 1β. Received: 15 March 1997 / Accepted: 11 June 1997  相似文献   

15.
On the basis of literature data and own experience the authors review the current knowledge about the molecular basis of inherited predispositions for tumors. They hypothesize that in the near perspective 5-10 years studies using existing registry data/material and the latest novel technology will allow the identification of the molecular background for the majority of hereditary cancers which will have enormous practical consequences especially for the prevention of malignancies.  相似文献   

16.
17.
Summary Tumor-infiltrating lymphocytes (TIL) were isolated from 22 human primary and metastatic liver tumors, and expanded in vitro in the presence of either interleukin-2 (IL-2, 100 U/ml) plus tumor necrosis factor (TNF, 1000 U/ml), IL-2 (1000 U/ml) plus IL-4 (1000 U/ml) or IL-2 (1000 U/ml) alone. TIL proliferated in culture in 20/22 cases. Among different cytokine combinations, TNF and IL-2 were most effective in promoting the outgrowth of CD3+ CD8+ T lymphocytes (mean ± SEM: 90%±5) in the cultures of TIL from primary liver tumors. Cytotoxicity against autologous tumor cells was demonstrated in all early cultures of TIL from primary liver cancers in the presence of IL-2 plus TNF. In contrast, cultures of TIL derived from colon cancer metastatic to liver had significantly lower levels of autotumor cytotoxicity and proportions of CD3+ CD8+ cells (40%±13) than those of TIL from primary liver tumors. The addition on day 0 of interferons ( or ) to TIL cultured in the presence of TNF and IL-2, significantly augmented cytotoxicity against autologous tumor. In contrast, incubation of TIL in the presence of IL-4 and IL-2 did not result in increased autotumor responses in the cultures of TIL from primary liver tumors. The expansion (-fold) of TIL (day 30) cultured in the presence of IL-2 alone compared to that in the presence of TNF and IL-2 was significantly greater for hepatocellular carcinoma (median, 280 vs 260) than for autologous peripheral blood lymphocytes (36 vs 27), cholangiocarcinoma (42 vs 51) or TIL from metastatic colon cancer (39 vs 30). Outgrowth of TIL in IL-2 plus TNF offers an opportunity for in vitro enrichment in cells with autotumor cytotoxicity in primary liver tumors. However, this cytokine combination was unable to promote and sustain growth of autotumor effectors from TIL in metastatic liver cancer.Supported by ACS grants IM27 077 and IM588 A (TLW) and Organ Transplant Program Project 1P01-CA-4744501 AZ  相似文献   

18.
An efficent antitumor and antiviral cellular immune response requires optimal interferon-gamma (IFN-gamma) secretion and perforin expression in CD8(+) T cells. The aim of this study was to define whether CD4(+) and CD8(+) T cells from patients with undifferentiated carcinoma of nasopharyngeal type (UCNT), a tumor regularly associated with the Epstein-Barr virus (EBV), have abnormal phenotype profiles, cytokine production, perforin and CD3-zeta expressions. Our data showed that CD4 and CD8 subset distribution was not grossly altered in the peripheral blood of UCNT patients, while tumor biopsies contained an increased proportion of CD8(+) T cells. The analysis of the CD4(+) subset showed a defect in interleukin-2 (IL-2) production and a moderate increase of IL-10 production, a situation consistent with a Th1/Th2 imbalance. We have also demonstrated that CD8(+) lymphocytes from UCNT patients had a marked impairment of IFN-gamma secretion and perforin expression. This impairment was not related to the presence of detectable EBV DNA in the plasma. In UCNT patients, the blockade of the perforin pathway and of IFN-gamma production may constitute important mechanisms for immune escape by the tumor and for impaired control of EBV replication.  相似文献   

19.
Summary Previous studies have indicated that primary but not metastatic melanomas were able to stimulate the proliferation of autologous (Auto) peripheral blood lymphocytes (PBL) in 73% of cases. On the other hand, 57% of the metastatic melanomas were shown to be suppressive when melanoma cells (Me) were admixed with Auto-PBL stimulated with allogeneic (Allo) PBL or interleukin 2 (IL-2) at the beginning of a 6-day incubation period. Here, we report that the suppressive activity of Me is a functional characteristic associated with a particular stage of the disease. In fact, we found that none of the 11 primary tumors tested were able to inhibit the proliferative response of Auto-PBL to Allo-PBL or IL-2 at all the doses of tumor cells used. The generation of lymphocytes cytotoxic against Auto-Me or K562 was also not inhibited. Of the 11 primary tumors checked for suppression, 8 were able to stimulate Auto-PBL in a primary mixed lymphocyte tumor culture. We conclude that opposite functions, stimulation and inhibition of autologous lymphocyte responses are characteristics of primary and metastatic Me, respectively.This work was supported in part by the Italian Association for Cancer Research (Milan) and by grants # 85.02162.44 and 86.00663.44 of the Finalized Project Oncology of CNR of Rome, Italy  相似文献   

20.
Tumors create a unique immunosuppressive microenvironment (tumor microenvironment, TME) whereby leukocytes are recruited into the tumor by various chemokines and growth factors. However, once in the TME, these cells lose the ability to promote anti-tumor immunity and begin to support tumor growth and down-regulate anti-tumor immune responses. Studies on tumor-associated leukocytes have mainly focused on cells isolated from tumor-draining lymph nodes or spleen due to the inherent difficulties in obtaining sufficient cell numbers and purity from the primary tumor. While identifying the mechanisms of cell activation and trafficking through the lymphatic system of tumor bearing mice is important and may give insight to the kinetics of immune responses to cancer, in our experience, many leukocytes, including dendritic cells (DCs), in tumor-draining lymph nodes have a different phenotype than those that infiltrate tumors. Furthermore, we have previously demonstrated that adoptively-transferred T cells isolated from the tumor-draining lymph nodes are not tolerized and are capable of responding to secondary stimulation in vitro unlike T cells isolated from the TME, which are tolerized and incapable of proliferation or cytokine production. Interestingly, we have shown that changing the tumor microenvironment, such as providing CD4(+) T helper cells via adoptive transfer, promotes CD8(+) T cells to maintain pro-inflammatory effector functions. The results from each of the previously mentioned studies demonstrate the importance of measuring cellular responses from TME-infiltrating immune cells as opposed to cells that remain in the periphery. To study the function of immune cells which infiltrate tumors using the Miltenyi Biotech isolation system, we have modified and optimized this antibody-based isolation procedure to obtain highly enriched populations of antigen presenting cells and tumor antigen-specific cytotoxic T lymphocytes. The protocol includes a detailed dissection of murine prostate tissue from a spontaneous prostate tumor model (TRansgenic Adenocarcinoma of the Mouse Prostate -TRAMP) and a subcutaneous melanoma (B16) tumor model followed by subsequent purification of various leukocyte populations.  相似文献   

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