Active specific immunotherapy of Dukes B2 and C colorectal carcinoma: Comparison of two doses of the vaccine

Summary The ability of active specific immunotherapy to enhance immune responses to autologous tumor-associated antigens (TAA) and to prolong the disease-free interval was evaluated in patients with Dukes B₂ and C colorectal carcinoma who had undergone potentially curative resections. Patients were sensitized in the early postoperative period with irradiated autologous adenocarcinoma cells mixed with bacillus Calmette-Guérin (BCG) to yield either a low-dose vaccine (3×10⁶ tumor cells) or a high-dose vaccine (1×10⁷ tumor cells). Six of seven patients who received the low-dose vaccine developed delayed-type hypersensitivity (DTH) responses to autologous tumor cells upon completion of the vaccination, whereas all four patients receiving high-dose vaccine displayed a positive DTH response. However, DTH responses to autologous TAA waned within 3 months in all patients receiving the low-dose vaccine; DTH responses persisted for 3 months in three of the four high-dose vaccine patients. In vitro lymphoproliferative responses to TAA correlated with DTH responses to autologous tumor cells. Active specific immunotherapy appeared to induce specific immune responses either in vitro or in vivo to autologous TAA because it did not induce responses to autologous mucosa cells. There were no complications caused by BCG or tumor cells. This series demonstrates that active specific immunotherapy is a nontoxic treatment that augments immunity to autologous TAA.This project was supported by grants from Cutter Laboratories, Inc., the Annual Campaign of the University of Texas System Cancer Center, and the National Cancer Cytology Center     

Tissue-specific differences in metabolites and transcripts contribute to the heterogeneity of ricinoleic acid accumulation in Ricinus communis L. (castor) seeds

Metabolomics - Up to now, quality assurance (QA) and quality control (QC) in metabolomics are procedures that most labs did using their own in-house developed procedures and rules since there was...     

Adaptive evolution of a melanized fungus reveals robust augmentation of radiation resistance by abrogating non-homologous end-joining

Fungi have been observed to exhibit resistance to high levels of ionizing radiation despite sharing most DNA repair mechanisms with other eukaryotes. Radioresistance, in fact, is such a common feature in fungi that it is difficult to identify species that exhibit widely different radiosensitivities, which in turn has hampered the identification of genetic elements responsible for this resistance phenotype. Due to the inherent mutagenic properties of radiation exposure, however, this can be addressed through adaptive laboratory evolution for increased ionizing radiation resistance. Here, using the black yeast Exophiala dermatitidis, we demonstrate that resistance to γ-radiation can be greatly increased through repeated rounds of irradiation and outgrowth. Moreover, we find that the small genome size of fungi situates them as a relatively simple functional genomics platform for identification of mutations associated with ionizing radiation resistance. This enabled the identification of genetic mutations in genes encoding proteins with a broad range of functions from 10 evolved strains. Specifically, we find that greatly increased resistance to γ-radiation is achieved in E. dermatitidis through disruption of the non-homologous end-joining pathway, with three individual evolutionary paths converging to abolish this DNA repair process. This result suggests that non-homologous end-joining, even in haploid cells where homologous chromosomes are not present during much of the cell cycle, is an impediment to repair of radiation-induced lesions in this organism, and that the relative levels of homologous and non-homologous repair in a given fungal species may play a major role in its radiation resistance.     

Phosphorus deprivation affects composition and spatial distribution of membrane lipids in legume nodules

In legumes, symbiotic nitrogen (N) fixation (SNF) occurs in specialized organs called nodules after successful interactions between legume hosts and rhizobia. In a nodule, N-fixing rhizobia are surrounded by symbiosome membranes, through which the exchange of nutrients and ammonium occurs between bacteria and the host legume. Phosphorus (P) is an essential macronutrient, and N₂-fixing legumes have a higher requirement for P than legumes grown on mineral N. As in the previous studies, in P deficiency, barrel medic (Medicago truncatula) plants had impaired SNF activity, reduced growth, and accumulated less phosphate in leaves, roots, and nodules compared with the plants grown in P sufficient conditions. Membrane lipids in M. truncatula tissues were assessed using electrospray ionization–mass spectrometry. Galactolipids were found to increase in P deficiency, with declines in phospholipids (PL), especially in leaves. Lower PL losses were found in roots and nodules. Subsequently, matrix-assisted laser desorption/ionization–mass spectrometry imaging was used to spatially map the distribution of the positively charged phosphatidylcholine (PC) species in nodules in both P-replete and P-deficient conditions. Our results reveal heterogeneous distribution of several PC species in nodules, with homogeneous distribution of other PC classes. In P poor conditions, some PC species distributions were observed to change. The results suggest that specific PC species may be differentially important in diverse nodule zones and cell types, and that membrane lipid remodeling during P stress is not uniform across the nodule.

ESI–MS and matrix-assisted laser desorption ionization–mass spectrometry imaging reveal alterations in Medicago truncatula nodules membrane lipid composition and spatial distribution in phosphorus deficiency.     

Effect of surgical stress on murine natural killer cell cytotoxicity

Natural killer cell cytotoxicity (NKCC) against tumors may be important in preventing in vivo solid tumor dissemination. Multiple animal models demonstrate increased rates of tumor dissemination after surgical stress; previously, we have observed that surgical stress impairs murine NKCC. Because of the importance of surgery in the control of solid tumors, it appeared valuable to examine the mechanism underlying surgical stress impairment of NKCC. The results of this study demonstrate that postsurgical suppression of NKCC begins as early as 2 hr after murine hind limb amputation, reaches nadir at 4 days, and does not recover to control level until postoperative day 12. Anesthetic treatment alone does not cause comparable NKCC suppression. The suppression of NKCC accompanied changes in both splenic size and morphology. The immune suppression was observed in multiple compartments including peripheral blood, bone marrow, and spleen. Mixing experiments demonstrated that surgical stress per se generated a suppressor cell population affecting NKCC. The observed suppression apparently required cell-to-cell contact, because supernatants from 4 and 18 hr cultures of suppressor cells did not cause suppression. The observed suppression was prevented by perioperative treatment with the pyrimidinone analog 2-amino-5-bromo-6-phenyl-4-pyrimidinol. These preclinical observations point to the future prospect of NK-specific perioperative immunotherapy that may help prevent possible tumor dissemination from occurring at the time of surgery.