Naturally occurring prostate cancer antigen-specific T cell responses of a Th1 phenotype can be detected in patients with prostate cancer

BACKGROUND: Cytotoxic T cells (CTL) are considered one of the primary effector cell populations in antitumor immunity. Recent studies, however, have demonstrated the critical importance of helper T cells (Th), specifically interferon gamma (IFN gamma)-secreting Th1 cells, either by supporting an appropriate CTL environment or by recruiting other effector cells. We evaluated whether patients with prostate cancer have naturally occurring Th-cell responses specific for two prostate cancer-associated antigens, prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP), and whether Th1-type responses to these antigens could be detected. METHODS: Peripheral blood mononuclear cells (PBMC) were collected from 80 patients with prostate cancer and 20 male controls without prostate disease. Th-cell responses were evaluated by measuring antigen-specific proliferation. IFN gamma and IL-5 secretion in response to antigen stimulation was determined by enzyme-linked immunosorbent assay. RESULTS: T cell proliferative responses specific for PSA and PAP could be detected in patients with prostate cancer. Six percent (5/80) of patients had T cell responses specific for PSA and 11% (9/80) for PAP. T cell responses specific for PSA were more prevalent in patients with metastatic disease (P = 0.02), whereas responses specific for PAP could be detected in patients irrespective of disease stage. IFN gamma-producing Th cells, specific for both PSA and PAP, could be identified in patients with prostate cancer. CONCLUSIONS: Patients with prostate cancer can have detectable Th-cell responses specific for the prostate cancer-associated proteins PSA and PAP. The presence of antigen-specific Th1 immune responses in prostate cancer patients suggests that an immune environment capable of supporting antigen-specific CTL may exist in vivo. Prostate 47:222-229, 2001.     

Inhibition of antigen-specific activation of an L3T4+ T cell line by cyclosporine with maintenance of macrophage-mediated antigen presentation

Cyclosporine has clearly been shown to directly inhibit T lymphocyte activation by monoclonal antibodies or mitogens where nominal antigen and accessory cells are not present. However, when T lymphocytes are stimulated by antigen, as occurs in allograft rejection, T lymphocytes and accessory cells must interact with one another. Under the latter circumstances, the issue of whether cyclosporine acts on T lymphocyte, accessory cell, or both is not resolved. This issue is addressed in this study. To assess the effect of cyclosporine on T cell activation, macrophages were incubated with heat-killed Listeria and then fixed in paraformaldehyde. These fixed macrophages retained their ability to present antigen to T cells but were not affected by subsequent treatment with cyclosporine. When cyclosporine and a L3T4+ T lymphocyte line were added simultaneously to fixed, antigen-pulsed macrophages, the drug inhibited antigen-specific T cell activation with a half maximal inhibitory concentration of 10 ng/ml. To our knowledge, this is the first evidence that low doses of cyclosporine inhibit antigen-specific T cell activation where the drug's effects on antigen-presenting cells have been excluded. To assess the effects of cyclosporine on macrophage-mediated antigen-presentation, macrophages were exposed simultaneously to cyclosporine and antigen, and then fixed. Antigen-presentation was not inhibited unless extremely large doses (9000 ng/ml) of cyclosporine were used. In our experimental system, any new inhibitory activity acquired by live cyclosporine-treated macrophages could be explained by residual drug. Finally, cyclosporine did not inhibit the induction of macrophage Ia expression nor antigen-presenting function after stimulation in vitro with lymphokine.     

Patients with distant metastases from renal cell carcinoma can be accurately identified: external validation of a new nomogram

OBJECTIVE

To identify clinical variables that can accurately predict the presence of distant metastases in patients with renal cell carcinoma (RCC).

PATIENTS AND METHODS

Age, symptom classification, tumour size and the prevalence of distant metastases at diagnosis before nephrectomy were available for 5376 patients with pathologically confirmed RCC. The data of 2660 (49.5%) patients from 11 centres were used to develop a multivariable logistic regression model‐based nomogram predicting the individual probability of distant metastases. The remaining data from 2716 (50.5%) patients from three institutions were used for external validation.

RESULTS

In the development cohort, 269/2660 (10.1%) had distant metastases, vs 285/2716 (10.5%) in the external validation cohort. Symptom classification and tumour size were independent predictors of distant metastases in the development cohort; age was not an independent predictor. A nomogram based on symptom classification and tumour size was 85.2% accurate in predicting the individual probability of distant metastases in the external validation cohort.

CONCLUSION

Although distant metastases might be easily identifiable in some patients, their diagnosis might be a challenge in others. The current nomogram provides a simple, user‐friendly and, most importantly, an accurate tool aimed at predicting the probability of distant metastases in patients with RCC.     

Lung adenocarcinoma can be subtyped according to tumor dimension by computed tomography mediastinal-window setting. Additional size criteria for clinical T1 adenocarcinoma

Objective: We sought to verify that the size of the solid component, which can be evaluated using the computed tomography mediastinal-window setting, provides new criteria for CT classification of lung adenocarcinoma. Methods: Between 1994 and September 2002, we examined 60 patients who were clinically classified with stage T1 adenocarcinoma of the lung and normal serum CEA, who underwent standard surgical procedures. Tumor maximum dimension was evaluated using two different CT-imaging settings: the lung window (lDmax), and the mediastinal window (mDmax). We analyzed the relationships between prognosis or lymph node involvement and tumor dimensions. Results: The mDmax was a significant (OR 1.11, P=0.02) predictive factor for lymph node metastasis. However, lDmax was not significant (P=0.83). Age, gender, lDmax, mDmax, and lymph node involvement were analyzed as predictive factors for prognosis. In univariate analysis, mDmax and lymph node involvement were significant predictive factors for prognosis (OR 1.07, P=0.01; OR 2.56, P=0.04; respectively). In multivariate analysis, mDmax was a significant predictive factor for prognosis (OR 1.06, P=0.04). We then classified the C-T1 adenocarcinoma patients into three groups according to mDmax: T1a (≤10 mm), T1b (from 11 to 20 mm), and T1c (from 21 to 30 mm). There was a significant difference between the three groups: the disease-free 5-year survivals were 93.3, 58.1, and 32.7%, respectively (P=0.01). Conclusions: The mDmax can give additional, useful prognostic data. This finding may provide new criteria for CT classification of lung adenocarcinoma.     

Induction of tumor regression by passive transfer of antibody from mice vaccinated with anti-idiotype antibodies resembling a human renal cell carcinoma-associated antigen

We have shown that six different internal image antiidiotype antibodies (Ab2) raised against the combining site of the murine monoclonal antibody G250 (MAbG250; Abl), which specifically reacts with a human renal cell carcinoma (RCC)-associated antigen, induce antigen specific humoral and cellular responses in mice. These six Ab2 can be divided into four mutually exclusive groups: (1) NUH31 and NUH51, (2) NUH44 and NUH82, (3) NUH71, and (4) NUH91. Immunization with NUH82 or NUH91 resulted in Ab3 sera that gave complete protection against tumor challenge. In this study, we tested the antitumor efficacy of NUH82- and NUH91-induced mouse sera (Ab3 sera; Ab3-82 and Ab3-91) in mice with established subcutaneous human RCC xenografts. Mice were treated 3 times per week by intraperitoneal injection of Ab3 sera (0.2 ml) or MAbG250 (250 μg) for 6 weeks. Treatment of NU12 human RCC xenografts of approximately 20 mm(3) expressed as tumor size index (TSI) with NUH-Ab3 sera or MAbG250 resulted in significant tumor growth inhibition compared with tumors treated with Ab3 sera from mice immunized with control immunoglobulin (Ab3-MOPC). In all Ab3-NUH treated mice, tumors stabilized or disappeared completely. In contrast, Ab3-MOPC treatment did not result in any antitumor effects. Tumor remnants in Ab3-NUH treated animals contained viable tumor cells surrounded by infiltrating mouse cells, whereas no infiltration was observed in control tumors. These findings demonstrate that Ab3 sera obtained from NUH82- or NUH91-immunized mice are very effective in eradicating established RCC [i.e., Ab2 vaccination may be able to eradicate (minimal) residual disease in RCC patients].     

Rejection of grafts without histocompatibility antigen disparity by TAP1-/- mice: a role for CD4+ T cells

We have previously shown that TAP1-/- mice reject heart and skin grafts lacking an H-2 disparity. TAP1-/- mice, which are deficient for MHC-I molecules, probably have a T-cell repertoire with distinct reactivity to these molecules. We speculated that this rejection could be mediated by CD4+ T cells reactive to H-2(b) class I molecules, or to class I-derived peptides presented by self-APC. This hypothesis was tested in the present work. Presensitization of TAP1-/- mice with H-2K(b) peptides accelerated the rejection of C57BL/6 (H-2(b)) skin grafts (MST 13 days, P <.0057), indicating that these peptides were able to mobilize effector T cells that participate in rejection. In addition, CD4 T-cell depletion before transplantation induced a significant delay in rejection (P <.0011), showing that CD4 T cells have a major role in the rejection process, though other cells may also contribute. In conclusion, these results support our hypothesis that H-2(b) molecules may be targeted in graft rejection without an H-2 disparity. The low expression of MHC-I molecules on TAP1-/- mice may determine the selection of a T-cell repertoire that is reactive to self-MHC-I molecules, a phenomenon that is probably beyond the control of peripheral regulatory mechanisms.     

NOD/SCID mice engrafted with human peripheral blood lymphocytes can be a model for investigating B cells responding to blood group A carbohydrate determinant

Human antibodies (Abs) against blood group A or B carbohydrate determinant are a major barrier to ABO-incompatible organ transplantation; however, the phenotype and other properties of B cell types responding to A or B carbohydrate epitopes have not been defined. Studies here, which use fluorescein-labeled synthetic A determinant (GalNAcalpha1-3Fucalpha1-2Gal), demonstrate that B cells bearing surface IgM (sIgM) receptors recognizing blood group A carbohydrate determinant are found exclusively in a small B cell subpopulation, i.e. sIgM+ CD11b+ CD5+ B1 cells, in blood group O human peripheral blood mononuclear cells (PBMC). In order to test anti-A Abs producing capacity of the human PBMC, nonobese diabetic (NOD)/severe combined immune-deficient (SCID) mice that have been treated with rabbit anti-asialo GM1 serum to deplete natural killer cells and with 3 Gy of whole body irradiation were engrafted with blood group O or A human PBMC, followed by sensitization of human blood group A red blood cells. Anti-A-specific human Abs were detected in the sera of the mice that received blood group O human PBMC, whereas they were not detected in the sera of the mice that received blood group A human PBMC, indicating profound tolerance of auto-reactive B cells. The human PBMC-NOD/SCID chimera developed by injection of blood group O human PBMC might be a useful in vivo model to test effects of immunosuppressants or other approaches on human B cells that respond to blood group A antigens.     

Neutralization of immunosuppression by antibodies against variable as well as constant regions of monoclonal anti-Thy-1 xenoantibodies and their ability to be suppressed by initial T cell depletion

Timing, magnitude, and effect of the murine antibody response to rat pan-T-cell antibodies were studied in a bone marrow (C57BL/6-to-CBA mice) transplantation model. Prospective C57BL/6 marrow donor mice were sensitized against pan-T-cell (Thy-1, Thy-1.2, Lyt-1) monoclonal antibodies of various rat isotypes or against polyclonal rat antimouse-thymocytes (rat ATG) antibodies. Three days prior to transfer of spleen and bone marrow cells, the sensitized C57BL/6 donors received a dose of anti-Thy-1 mAb (RmT1) known to abolish graft-versus-host reactivity of unsensitized donors. The injected mAb provoked anti-antibodies reacting with RmT1. The anti-antibodies inhibited immunosuppression of the rat mAb RmT1 even if they bound only to nonidiotypic epitopes on RmT1. Avoiding cell-binding of the sensitizing rat anti-Thy-1.2 mAb by its injection into Thy-1.1 mice induced only low-titer and delayed anti-antibodies. This indicated the enhanced immunization potential of anti-Thy-1 when bound to cells. Finally, sensitization leading to the mouse antirat anti-antibodies and reversion of immunosuppression was prevented or reduced considerably by T cell depletion with a mouse IgG2a anti-Thy-1.2 mAb or high-dose cyclophosphamide or by rabbit ATG, provided it was initiated before starting the sensitizing injections of the rat antimouse T cell antibodies.     

Large bowel obstruction due to colorectal carcinoma can be safely treated by colonic stent insertion – case series from a UK district general hospital

Aim The aim of this study is to audit our outcomes and experience of colonic stent insertion for malignant bowel obstruction. Method Retrospective audit of all stent insertions in a single district general hospital between August 2003 and December 2009. All patients had presented with acute bowel obstruction caused by malignant colorectal disease and details were collected prospectively and contemporaneously onto a database. Stent insertion was a combined endoscopic and fluoroscopic procedure involving a colorectal surgeon and consultant radiologist. Results Stenting was attempted on 62 occasions in 54 patients. The technical success rate was 86% and the clinical success rate 84%. The indications for stenting were for relief of acute bowel obstruction, palliation and as a bridge to surgery. There were complications in 14 cases (22.5%) including three perforations and one perioperative mortality. There were three cases of stent migration, six cases of re‐stenosis and two stents became impacted with stool. There were no incidents of acute or delayed haemorrhage in any patients. Conclusion Our experience shows that stenting for obstructing colorectal cancer is a safe and effective method of alleviating acute and impending bowel obstruction and can be provided safely and effectively in a district general hospital.     

Development and characterization of a rapidly proliferating, well-differentiated cell line derived from normal adult human osteoblast-like cells transfected with SV40 large T antigen.

A new bone cell line was established by transfecting normal adult human osteoblast-like (hOB) cells, derived from a 68-year-old woman, with the plasmid pSV3 neo. The plasmid included coding sequences and promotors for the large and small T antigens of the SV40 virus as well as resistance to the antibiotics neomycin and G418. A single antibiotic-resistant colony was located and cloned. Large tumor antigen production in the clonal cell line was confirmed by indirect immunofluorescence study. Treatment with 1,25-dihydroxy-vitamin D3 increased steady-state concentrations of protein and mRNA for osteocalcin and for alkaline phosphatase. Northern blot analyses also demonstrated the presence of mRNAs for alpha(I)-procollagen, osteopontin 1a, transforming growth factor beta, and interleukin-1 beta. The plasma membrane calcium pump and osteonectin were identified by immunocytochemical analysis. These cells produced a matrix that mineralized when beta-glycerophosphate was added to their cultures. As assessed by functional receptor assays, both estrogen and androgen receptors were present and functional, although at low concentrations. Treatment with parathyroid hormone did not stimulate adenylate cyclase activity. Thus, these cells are a well-differentiated, steroid-responsive clonal cell line that closely approximates the phenotype of the mature osteoblast. They should serve as an excellent model for the study of osteoblast biology.     

Association between renal mass biopsy and upstaging to perinephric fat involvement in a contemporary cohort of patients with clinical T1a renal cell carcinoma

Background

Although tumor tract seeding from renal mass biopsy (RMB) is exceedingly rare, the possibility of tumor capsule violation from RMB leading to perinephric fat invasion has not been quantified. We evaluated the association between RMB and perinephric fat invasion in patients with clinical T1a renal cell carcinoma who underwent partial or radical nephrectomy.

转化生长因子-β1联合白细胞介素-2体外诱导非肥胖糖尿病小鼠调节性T细胞的产生

目的 体外诱导非肥胖糖尿病(NOD)小鼠CD4+ CD25+Foxp3+调节性T细胞(Treg)的产生并检测其免疫抑制功能.探讨外源性白细胞介素(IL)-2在诱导方案中的作用.方法 分选NOD小鼠童贞T细胞(Naive T),利用Anti-CD3、Anti-CD28刺激,同时给予转化生长因子-β1(TGF-β1)和白细胞介素-2(IL-2),共同培养5 d,收获诱导性Treg(iTreg),经流式细胞仪检测其表型.利用体外T细胞增殖体系,对比NOD小鼠天然Treg(nTreg),评价iTreg的免疫抑制能力.将诱导方案中的IL-2撤除以观察其作用.结果 TGF-B1联合IL-2能诱导NOD小鼠Naive T转化为iTreg,较对照组有统计学意义[(41.33±3.21)%比(8.00±3.00)%,P《0.05].iTreg可有效抑制T细胞增殖,其能力与nTreg的差异元统计学意义[(40.33±1.03)%比(38.33±3.06),P》0.05].外源性IL-2有利于iTreg的产生[(41.33±3.21)%比(15.00±1.00)%,P《0.05].结论 TGF-β1联合IL-2可在体外诱导Naive T转化为具有免疫抑制功能的Treg.     

Inhibition of T cell homing by down-regulation of CD62L and the induction of a Th-2 response as a method to prevent acute allograft rejection in mice.

OBJECTIVE: For a successful immune response, migration of lymphocytes to lymphoid organs and other tissues is a key step, as the initial recognition of foreign antigens and activation of lymphocytes takes place in these organs. CD62L is a homing receptor that mediates entry of na?ve T cells to peripheral lymph nodes. Maybe the preventing of T cell homing will change the immune response against allogeneic tissue and suppress rejection. METHODS: We treated different mouse strains with pertussis toxin to manipulate T cell homing and measured the rejection of allografts in terms of allogeneic tumor cells. We transferred pertussis toxin treated or nontreated transgenic T cells into BALB/c wild type mice. The transgenic T cells could be followed ex vivo by specific antibodies. Cytokine production from purified (1x10(5)/ml) T cells after different stimulations in vitro and expression of surface markers on T cells following pertussis toxin treatment by FACS analysis were performed. RESULTS: Pertussis toxin-treated C57BL/6 mice with the MHC class I molecule H-2K(b) could not reject allogeneic tumor cells R1.1, which expressed the MHC class I molecule H-2K(k) and were killed by these cells. This allograft survival could be demonstrated for various allogeneic cells in different mouse strains with different MHC class I expression and emphasizes the general mechanism in these studies. In vivo CD62L expression on T cells was down-regulated by pertussis toxin in normal mice and transgenic mice that produce only one specific T cell, and after the pertussis toxin treatment the mice showed 4-5 times larger spleens compared to untreated mice. In transfer experiments, we demonstrated that CD62L low transgenic T cells could not home to lymph nodes. Furthermore, spleen cells from pertussis toxin-treated mice produced high amounts of the Th-2 cytokine interleukin 4 after stimulation in primary culture. CONCLUSIONS: Our data suggest that the inhibition of T cell homing changes the immune response. Prevention of homing of T cells in combination with the induction of a Th-2 response is a mechanism to prevent specific acute rejection of allogeneic tissue.