Allogeneic tumor-specific cytotoxic T lymphocytes

Summary We report the development of cytotoxic T lymphocytes specific for an allogeneic brain tumor in a rat model. DA strain cytotoxic T cell precursors stimulated by an allogeneic tumor (9L gliosarcoma) from the Fischer rat could generate a population of cytotoxic T lymphocytes that lysed the allogeneic 9L tumor but failed to lyse other targets, including Fischer concanavalin-A(ConA)-stimulated lymphoid blast targets. DA T cells depleted of reactivity to the Fischer haplotype (DA-f) retained reactivity to the 9L tumor, demonstrating that T cell precursors with specificity for normal Fischer alloantigens were not required for the generation of a response to the 9L Fischer tumor. The preferential lysis of the tumor target did not simply reflect a higher density of Fischer target antigens on the tumor than that found on normal Fischer ConA blast targets. First, the relative densities of class I antigen on the 9L tumor and normal Fischer ConA blasts were comparable. Second, cytotoxic T cells could not be generated from DA-f precursors when Fischer ConA blasts were used as stimulators. If DA-f T cells were simply responding to the higher density of Fischer antigen found on 9L tumor, it would have been expected that the ConA blasts expressing comparable levels of antigen to that found on the tumor would have generated cytotoxicity for both the 9L and ConA targets. We conclude that the cytotoxic T cells are specific for a determinant expressed only by the tumor. Such tumor-specific cytotoxic T cells could be useful in vivo for adoptive immunotherapy of brain tumors.     

Expression of human prostate-specific antigen (PSA) in a mouse tumor cell line reduces tumorigenicity and elicits PSA-specific cytotoxic T lymphocytes

 Human prostate-specific antigen (PSA) has a highly restricted tissue distribution. Its expression is essentially limited to the epithelial cells of the prostate gland. Moreover, it continues to be synthesized by prostate carcinoma cells. This makes PSA an attractive candidate for use as a target antigen in the immunotherapy of prostate cancer. As a first step in characterizing the specific immune response to PSA and its potential use as a tumor-rejection antigen, we have incorporated PSA into a well-established mouse tumor model. Line 1, a mouse lung carcinoma, and P815, a mouse mastocytoma, have been transfected with the cDNA for human PSA. Immunization with a PSA-expressing tumor cell line demonstrated a memory response to PSA which protected against subsequent challenge with PSA-expressing, but not wild-type, tumors. Tumor-infiltrating lymphocytes could be isolated from PSA-expressing tumors grown in naive hosts and were specifically cytotoxic against a syngeneic cell line that expressed PSA. Immunization with tumor cells resulted in the generation of primary and memory cytotoxic T lymphocytes (CTL) specific for PSA. The isolation of PSA-specific CTL clones from immunized animals further demonstrated that PSA can serve as a target antigen for antitumor CTL. The immunogenicity studies carried out in this mouse tumor model provide a rationale for the design of methods to elicit PSA-specific cell-mediated immunity in humans. Received: 4 April 1996 / Accepted: 31 May 1996     

Pre-immunotherapy serum CA27.29 (MUC-1) mucin level and CD69+ lymphocytes correlate with effects of Theratope® sialyl-Tn-KLH cancer vaccine in active specific immunotherapy

Patients with metastatic breast, colorectal or ovarian cancers received active specific immunotherapy (ASI) with Theratope® sialyl-Tn-KLH (keyhole limpet hemocyanin) cancer vaccine emulsified in Detox? adjuvant. The median log₂ anti-STn IgG titer generated by ASI, estimated by enzyme-linked immunosorbent assay with solid-phase ovine submaxillary mucin, was 5.322 (range = 0?–?9.322). Following ASI, 51 patients who generated titers higher than the median value for anti-STn⁺ mucin IgG survived longer than 46 patients who generated lower titers below the median. 38 of the patients were phenotyped for CD69 prior to ASI. The patients with lower numbers of CD69⁺ peripheral blood lymphocytes prior to immunotherapy (pre-ASI) also had low serum CA27.29 cancer antigen (MUC-1) levels, and had longer times to disease progression and improved survival following ASI. Elevated pre-ASI serum CA27.29 tumor antigen levels were associated with higher numbers of CD69⁺ PBL, with decreased anti-STn antibody production and decreased survival following ASI. The data are compatible with the hypothesis that elevated serum MUC-1 mucin is specifically immunosuppressive.     

The role of cancer metabolism in defining the success of oncolytic viro-immunotherapy

Oncolytic viruses infect, replicate in, and kill cancer cells selectively without harming normal cells. The rapidly expanding clinical development of oncolytic virotherapy is an exciting interdisciplinary field that provides insights into virology, oncology, and immunotherapy. Recent years have seen greater focus on rational design of cancer-selective viruses together with strategies to exploit their immunostimulatory capabilities, ultimately to develop powerful oncolytic cancer vaccines. However, despite great interest in the field, many important experiments are still conducted under optimum conditions in vitro, with many nutrients present in excess and with cellular stress kept to a minimum. Whilst this provides a convenient platform for cell culture, it bears little relation to the typical conditions found within a tumour in vivo, where cells are often subject to a range of metabolic and environmental stresses. Viral infection and cancer will both lead to production of metabolites that are also not present in media in vitro. Understanding how oncolytic viruses interact with cells exposed to more representative metabolic conditions in vitro represents an under-explored area of study that could provide valuable insight into the intelligent design of superior oncolytic viruses and help bridge the gap between bench and bedside. This review summarises the major metabolic pathways altered in cancer cells, during viral infection and highlights possible targets for future studies.     

Antibody Uptake into Neurons Occurs Primarily via Clathrin-dependent Fcγ Receptor Endocytosis and Is a Prerequisite for Acute Tau Protein Clearance

Tau immunotherapy is effective in transgenic mice, but the mechanisms of Tau clearance are not well known. To this end, Tau antibody uptake was analyzed in brain slice cultures and primary neurons. Internalization was rapid (<1 h), saturable, and substantial compared with control mouse IgG. Furthermore, temperature reduction to 4 °C, an excess of unlabeled mouse IgG, or an excess of Tau antibodies reduced uptake in slices by 63, 41, and 62%, respectively (p = 0.002, 0.04, and 0.005). Uptake strongly correlated with total and insoluble Tau levels (r² = 0.77 and 0.87 and p = 0.002 and 0.0002), suggesting that Tau aggregates influence antibody internalization and/or retention within neurons. Inhibiting phagocytosis did not reduce uptake in slices or neuronal cultures, indicating limited microglial involvement. In contrast, clathrin-specific inhibitors reduced uptake in neurons (≤78%, p < 0.0001) and slices (≤35%, p = 0.03), demonstrating receptor-mediated endocytosis as the primary uptake pathway. Fluid phase endocytosis accounted for the remainder of antibody uptake in primary neurons, based on co-staining with internalized dextran. The receptor-mediated uptake is to a large extent via low affinity FcγII/III receptors and can be blocked in slices (43%, p = 0.04) and neurons (53%, p = 0.008) with an antibody against these receptors. Importantly, antibody internalization appears to be necessary for Tau reduction in primary neurons. Overall, these findings clarify that Tau antibody uptake is primarily receptor-mediated, that these antibodies are mainly found in neurons with Tau aggregates, and that their intracellular interaction leads to clearance of Tau pathology, all of which have major implications for therapeutic development of this approach.     

母牛分支杆菌菌苗治疗糖尿病合并初治肺结核的临床分析

目的 探讨母牛分支杆菌菌苗（简称微卡）治疗糖尿病合并肺结核的疗效。方法 同期选取40例糖尿病合并肺结核初治患者,随机分为A、B组。A组以常规抗痨治疗（2HRZE／4HR）,B组在常规抗痨治疗的基础上加用微卡治疗2月。结果 B组结核病灶消散吸收、空洞完全或部分闭合、痰结核菌阴转速度均明显快于A组（P〈0．05）,且不良反应少见。结论 微卡可用作糖尿病合并肺结核的免疫治疗。     

Percutaneous comprehensive cryoablation for metastatic esophageal cancer after failure of radical surgery

Esophageal cancer is common in China. There is a lack of treatment strategies for metastatic esophageal cancer (MEC) after radical surgery on the primary tumor. Cryoablation is an attractive option because tumor necrosis can be safely induced in a minimally invasive manner. This study assessed its therapeutic effect in MEC after failure of radical surgery. One hundred and forty patients met the inclusion criteria from May, 2003 to March, 2011. Comprehensive cryotherapy of multiple metastases was performed on 105 patients; 35 received chemotherapy. No severe complications occurred during or after cryoablation. Overall survival (OS) was assessed according to therapeutic protocol, pathologic type, treatment timing and number of procedures. The OS of patients who received comprehensive cryoablation (44 ± 20 months) was significantly longer than that of those who underwent chemotherapy (23 ± 24 months; P = 0.0006). In the cryotherapy group, the OS for squamous cell carcinoma (45 ± 19 months) was longer than that for adenocarcinoma (33 ± 18 months; P = 0.0435); the OS for timely cryoablation (46 ± 19 months) was longer than that for delayed cryoablation (33 ± 20 months; P = 0.0193); the OS for multiple cryoablation (50 ± 17 months) was longer than that for single cryoablation (37 ± 20 months; P = 0.0172); and the OS for cryo-immunotherapy (56 ± 17 months) was longer than that for cryoablation alone (39 ± 19 months; P = 0.0011). Thus, comprehensive cryotherapy may have advantages over chemotherapy in the treatment of MEC and, in patients with squamous cell carcinoma, supplementary immunotherapy and timely and multiple cryoablation may be associated with a better prognosis.     

Heat shock proteins: A dual carrier-adjuvant for an anti-drug vaccine against heroin

Heroin is a highly abused opioid that has reached epidemic status within the United States. Yet, existing therapies to treat addiction are inadequate and frequently result into rates of high recidivism. Vaccination against heroin offers a promising alternative therapeutic option but requires further development to enhance the vaccine’s performance. Hsp70 is a conserved protein with known immunomodulatory properties and is considered an excellent immunodominant antigen. Within an antidrug vaccine context, we envisioned Hsp70 as a potential dual carrier-adjuvant, wherein immunogenicity would be increased by co-localization of adjuvant and antigenic drug hapten. Recombinant Mycobacterium tuberculosis Hsp70 was appended with heroin haptens and the resulting immunoconjugate granted anti-heroin antibody production and blunted heroin-induced antinociception. Moreover, Hsp70 as a carrier protein surpassed our benchmark Her-KLH cocktail through antibody-mediated blockade of 6-acetylmorphine, the main mediator of heroin’s psychoactivity. The work presents a new avenue for exploration in the use of hapten-Hsp70 conjugates to elicit anti-drug immune responses.