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Davis TA, Suryawan A, Orellana RA, Nguyen HV, Fiorotto ML. Postnatal ontogeny of skeletal muscle protein synthesis in pigs. J Anim Sci 2007; 86:E13-8. [PMID: 17785597 PMCID: PMC2640319 DOI: 10.2527/jas.2007-0419] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The neonatal period is characterized by rapid growth and elevated rates of synthesis and accretion of skeletal muscle proteins. The fractional rate of muscle protein synthesis is very high at birth and declines rapidly with age. The elevated capacity for muscle protein synthesis in the neonatal pig is driven by the high ribosome content and, together with an increased efficiency of the translation process, promotes accelerated protein synthesis rates. Feeding profoundly stimulates muscle protein synthesis in neonatal pigs and the response decreases with age. The feeding-induced stimulation of muscle protein synthesis is modulated by an enhanced sensitivity to the postprandial increase in insulin and amino acids. The developmental decline in the response to insulin and amino acids parallels a marked decrease in the feeding-induced activation of translation initiation factors that regulate the binding of mRNA to the 40S ribosomal complex. The abundance and activation of many known positive regulators of the nutrient- and insulin-signaling pathways that are involved in translation initiation are high, whereas those of many negative regulators are low in skeletal muscle of younger pigs. Thus, the activation and(or) abundance of the positive regulators, such as the insulin receptor, insulin receptor-substrate-1, phosphoinositide-3 kinase, phosphoinositide-dependent kinase-1, protein kinase B, mammalian target of rapamycin, raptor, ribosomal protein S6 kinase-1, eukaryotic initiation factor (eIF) 4E-binding protein 1, and eIF4E associated with eIF4G, are greater in 7-d-old pigs than in 26-d-old pigs. The activation of negative regulators, including protein tyrosine phosphatase-1B, phosphatase and tensin homologue deleted on chromosome 10, protein phosphatase 2A, and tuberous sclerosis complex 1/2, are lower in 7-d-old pigs than in 26-d-old pigs. Thus, the developmental decline in the stimulation of skeletal muscle protein synthesis by insulin and amino acids is due in part to the developmentally related decrease in the activation of the signaling pathways that lead to translation initiation.
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MacGill RS, Davis TA, Macko J, Mauceri HJ, Weichselbaum RR, King CR. Local gene delivery of tumor necrosis factor alpha can impact primary tumor growth and metastases through a host-mediated response. Clin Exp Metastasis 2007; 24:521-31. [PMID: 17653822 DOI: 10.1007/s10585-007-9089-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2006] [Accepted: 07/05/2007] [Indexed: 01/07/2023]
Abstract
TNFerade is a replication incompetent adenovector designed to express human TNFalpha under control of the Egr-1 radiation and chemotherapy enhanced promoter, and is currently in Phase II/III clinical testing. Data from Phase I clinical testing of TNFerade in a limited set of melanoma patients suggested the potential to impact distal metastases following intratumoral injections of TNFerade. These clinical observations and the multiple potential mechanisms of TNFerade led us to hypothesize local treatment with TNFerade + radiation may impact metastatic disease. We explored this hypothesis in preclinical models using the spontaneously metastatic, syngeneic B16F10 murine melanoma model. Established subcutaneous B16F10 tumors were treated with intratumoral injections of TNFerade and localized 2 Gy fractionated radiation therapy, modeling the clinical treatment regimen. Following 10-14 days of treatment, mice were evaluated for metastases development in the iliac and axillary lymph nodes. Comparisons of metastatic burden to control groups indicated TNFerade +/- radiation suppressed the formation of metastases in the lymph nodes. Additional experiments in TNF receptor knockout mice, where the only possible effects are on tumor cells containing the TNFalpha receptor, indicate TNFerade's local and distal activities are critically dependent on a host-mediated response. These data provide direct preclinical evidence local therapy of a solid tumor with TNFerade can also reduce metastatic disease, in addition to effects on the treated lesion. Furthermore, our finding of a host dependant response(s) for TNFerade at both the treated tumor and on lymph node metastases suggest the potential for broad activity independent of tumor histology.
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Davis TA, Clarke TK, Mog SR, Landauer MR. Subcutaneous administration of genistein prior to lethal irradiation supports multilineage, hematopoietic progenitor cell recovery and survival. Int J Radiat Biol 2007; 83:141-51. [PMID: 17378522 DOI: 10.1080/09553000601132642] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
PURPOSE Genistein, a non-toxic isoflavone from soybeans, has immunomodulating and radioprotective properties. In this study we investigated the mechanism for genistein-induced radioprotection by evaluating the recovery of bone marrow cells and peripheral blood hematology in lethally irradiated mice. MATERIALS AND METHODS CD2F1 male mice received a single subcutaneous injection of genistein (200 mg/kg) 24 h prior to a lethal, total body irradiation dose (8.75 Gy) of cobalt-60 gamma radiation. Survival and hematopoietic reconstitution were evaluated over nine weeks post-irradiation. Hematopoietic progenitor colony-forming cell assays were used to assess the reconstitution of bone marrow after radiation-induced myelosuppression. RESULTS A total of 97% of genistein-treated mice survived after 30 days while 31% of vehicle-treated and 0% of untreated mice survived. The improvement in survival was related to accelerated neutrophil and platelet recovery, resulting from earlier and more pronounced multilineage, hematopoietic progenitor cell reconstitution in the femoral marrow compartment. Myeloid and erythroid progenitor cell numbers at day 15 post-irradiation were 6-fold to 20-fold higher in genistein-treated animals than in control animals. CONCLUSIONS These results demonstrate that a single subcutaneous administration of genistein 24 h before irradiation provides significant radioprotection to the hematopoietic progenitor cell compartment.
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O'Mahony D, Morris JC, Quinn C, Gao W, Wilson WH, Gause B, Pittaluga S, Neelapu S, Brown M, Fleisher TA, Gulley JL, Schlom J, Nussenblatt R, Albert P, Davis TA, Lowy I, Petrus M, Waldmann TA, Janik JE. A pilot study of CTLA-4 blockade after cancer vaccine failure in patients with advanced malignancy. Clin Cancer Res 2007; 13:958-64. [PMID: 17289891 DOI: 10.1158/1078-0432.ccr-06-1974] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
PURPOSE Eleven patients with progressive advanced malignancy after administration of a cancer vaccine received a fully human anti-CTLA-4 monoclonal antibody (ipilimumab). The primary end point was to determine drug toxicity. Tumor response, tumor-specific CD8+ T-cell immune responses, and modulation of CD4+ CD25+ FoxP3+ regulatory T-cell (Treg) numbers were secondary end points. EXPERIMENTAL DESIGN Three patients with colon cancer, four with non-Hodgkin's lymphoma, and four with prostate cancer were treated. The first dose was given at 3 mg/kg and subsequent doses were administered monthly at 1.5 mg/kg for a total of four cycles. RESULTS Tumor regression was observed in two patients with lymphoma; one of which obtained a partial response of 14-month duration. Ipilimumab was well tolerated with predominantly grade 1/2 toxicities. One drug-related grade 3 toxicity was observed. One patient died within 30 days of treatment due to progressive colon cancer. No increase in vaccine-specific T-cell responses was observed after therapy. Tregs as detected by expression of CD4+CD25+CD62L+ declined at early time points but rebounded to levels at or above baseline values at the time of the next infusion. CONCLUSIONS Ipilimumab treatment depressed Treg numbers at early time points in the treatment cycle but was not accompanied by an increase in vaccine-specific CD8+ T-cell responses in these patients previously treated with a variety of investigational anticancer vaccines. A partial response was observed in one patient with follicular lymphoma. A phase I/II trial evaluating ipilimumab in patients with follicular lymphoma is currently ongoing.
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Zhang J, Davis TA, Matthews MA, Drews MJ, LaBerge M, An YH. Sterilization using high-pressure carbon dioxide. J Supercrit Fluids 2006. [DOI: 10.1016/j.supflu.2005.05.005] [Citation(s) in RCA: 131] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Woodward AM, Davis TA, Silva AGS, Kirk JA, Leary JA. Large genomic rearrangements of both BRCA2 and BRCA1 are a feature of the inherited breast/ovarian cancer phenotype in selected families. J Med Genet 2006; 42:e31. [PMID: 15863663 PMCID: PMC1736061 DOI: 10.1136/jmg.2004.027961] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION A strong family history of breast and/or ovarian cancer can often be explained by small insertions, deletions, or substitutions in BRCA1 or BRCA2 and large genomic rearrangements in BRCA1. However, there is little evidence that genomic rearrangements are a major factor in BRCA2 associated breast cancer and the frequencies of rearrangements in BRCA1 in large clinic based populations are unknown. OBJECTIVE To investigate the frequency of large genomic rearrangements in BRCA1 and BRCA2 in a large clinic based population at high risk of developing breast and/or ovarian cancer. METHODS Multiplex ligation dependent probe amplification was used to comprehensively screen BRCA1 and/or BRCA2 in 312 index cases. RESULTS Three novel deletions detected in BRCA2 were found exclusively in families with at least one case of male breast cancer. Novel rearrangements in BRCA1 were detected mostly in families with both breast and ovarian cancer. Families with these mutations were significantly younger at average age of cancer diagnosis. CONCLUSION Screening for large genomic rearrangements in both BRCA1 and BRCA2 is strongly supported by this study, in particular in multiple case breast/ovarian families with a young age of onset (BRCA1) and families containing at least one case of male breast cancer (BRCA2).
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Cronin DP, Harlan LC, Clegg LX, Stevens JL, Yuan G, Davis TA. Patterns of care in a population-based random sample of patients diagnosed with non-Hodgkin's lymphoma. Hematol Oncol 2006; 23:73-81. [PMID: 16170828 DOI: 10.1002/hon.747] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
New therapies have enhanced treatment of non-Hodgkin's lymphoma (NHL), but extent of treatment use in community practice is unknown. We conducted a population-based study of NHL patients diagnosed in 1999 with histologically confirmed NHL (n = 947) residing in areas covered by the Surveillance, Epidemiology, and End Results program. We performed analyses to study factors associated with receipt of chemotherapy, radiation, and rituximab, and examine factors associated with mortality. Most patients presented with B-cell lymphoma (n = 828). Approximately 20% of patients received no therapy, over 60% received chemotherapy, and 12% received rituximab, alone or in combination. Patients aged 75 +, and males were less likely to have received chemotherapy (p = 0.01). There were no significant associations between receipt of rituximab and the factors analyzed. Patients who presented with B-symptoms or unknown B-symptom status were less likely to receive radiation (OR = 0.32 and 0.47, respectively, p = 0.0002) than asymptomatic patients. Cause-specific and all-cause mortality were significantly associated with patient age, race/ethnicity, gender, marital status, co-morbid conditions, and histological subgroup. Hispanic and African-Americans, patients age 75 +, males, unmarried patients, or patients with B-symptoms had higher risk of death from NHL and all-cause (p < 0.01). This is the first population-based study examining therapy received for many histological subtypes of NHL.
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Davis TA, Lennon G. Mice with a regenerative wound healing capacity and an SLE autoimmune phenotype contain elevated numbers of circulating and marrow-derived macrophage progenitor cells. Blood Cells Mol Dis 2005; 34:17-25. [PMID: 15607695 DOI: 10.1016/j.bcmd.2004.10.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2004] [Revised: 10/01/2004] [Indexed: 11/20/2022]
Abstract
Mice from the MRL strain are prone to develop systemic lupus erythematosus (SLE) and have demonstrated accelerated wound healing and scarless tissue regeneration; however, many of the mechanisms involved in these clinically relevant pathologies are unclear. Prior studies have described macrophage accumulation and functional defects in mice prone to lupus. Monocyte-macrophages have also been shown to have a high degree of plasticity. To determine whether there might be innate differences in the hematopoietic systems of MRL mice, we evaluated hematopoietic progenitor cell content in a variety of tissues and the proliferative responses of derived marrow and thioglycolate (TG)-elicited peritoneal macrophages. Our experiments reveal that MRL mice have significantly lower numbers of circulating blood leukocytes and platelets. Even more strikingly, we found that MRL blood and marrow contain an unusually robust number of unique and assayable macrophage colony-stimulating factor responsive cells which have the characteristics of macrophage colony-forming cell precursors. In culture, in contrast to cells derived from control C57BL/6 mice, this cell type and thioglycolate-elicited peritoneal macrophages from MRL mice can be extensively expanded with just macrophage colony-stimulating factor to acquire an in situ "f-mac-like" (see Y. Zhao, D. Glesne and E. Huberman, A human peripheral blood monocyte-derived subset acts as pluripotent stem cells. Proc. Natl. Acad. Sci. U.S.A. 100, (2003) 2426-2431.) morphology when plated on plastic surfaces. Our results suggest that these increased numbers of macrophage progenitor cells and their potential differentiation plasticity may play a functional role in the onset of systemic lupus erythematosus and may also contribute to the accelerated and scarless tissue regenerative repair response observed in MRL mice.
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Davis TA, Yezek LP, Pinheiro JP, van Leeuwen HP. Measurement of Donnan potentials in gels by in situ microelectrode voltammetry. J Electroanal Chem (Lausanne) 2005. [DOI: 10.1016/j.jelechem.2005.06.021] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Davis TA, Longcor JD, Hicok KC, Lennon GG. Prior injury accelerates subsequent wound closure in a mouse model of regeneration. Cell Tissue Res 2005; 320:417-26. [PMID: 15856306 DOI: 10.1007/s00441-005-1107-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2004] [Accepted: 02/21/2005] [Indexed: 10/25/2022]
Abstract
Tissue regeneration and scarless healing involves the complete replacement and functional restoration of damaged organs and tissues. In this study of the "scarless healing" MRL mouse model, we demonstrate that 2-mm diameter through-and-through holes made in the cartilaginous part of previously injured MRL mouse ears are closed more efficiently, and that the regenerative repair response is significantly accelerated compared with unprimed MRL and control "nonhealer" strains of mice. Accelerated healing was detected both locally and distally from the original site of injury indicating the involvement of systemic components such as circulating cell types or soluble factors. Histologically, we observed early differences during the wound repair process (before Day 4 post injury) with accelerated formation of blastema-like structures, epidermal downgrowths, and enhanced epithelium thickening in wound border zones in primed MRL mice versus unprimed MRL mice. Although the mechanism of tissue regeneration remains unclear, the results from this study justify the use of the MRL model for further experimentation directed toward the identification of proteins and cell types capable of stimulating scarless tissue regeneration.
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Koopal LK, Goloub TP, Davis TA. Binding of ionic surfactants to purified humic acid. J Colloid Interface Sci 2005; 275:360-7. [PMID: 15178260 DOI: 10.1016/j.jcis.2004.02.061] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2003] [Accepted: 02/24/2004] [Indexed: 10/26/2022]
Abstract
The binding of organic contaminants to dissolved humic acids reduces the free concentration of the contaminants in the environment and also may cause changes to the solution properties of humic acids. Surfactants are a special class of contaminants that are introduced into the environment either through wastewater or by site-specific contamination. The amphiphilic nature of both surfactants and humic acids can easily lead to their mutual attraction and consequently affect the solution behavior of the humics. Binding of an anionic surfactant (sodium dodecyl sulfate, SDS) and two cationic surfactants (dodecyl- and cetylpyridinium chloride, DPC and CPC) to purified Aldrich humic acid (PAHA) is studied at pH values of 5, 7, and 10 in solutions with a 0.025 M ionic strength (I). Monomer concentrations of the surfactants are measured with a surfactant-selective electrode. At I = 0.025 M, no significant binding is observed between the anionic surfactant (SDS) and PAHA, whereas the two cationic surfactants (DPC, CPC) bind strongly to PAHA over the pH range investigated. The binding is due both to electrostatic and hydrophobic attraction. The initial affinity increases with increasing pH (i.e., negative charge of PAHA) and tail length of the surfactant. Binding reaches a pseudo-plateau value (2-5 mmol/g) when the charge associated with PAHA is neutralized by that of the bound surfactant molecules. The pseudo-plateau values for DPC and CPC are very similar and depend on the solution pH. The cationic surfactant-PAHA complexes precipitate when the charge neutralization point is reached. This occurs at approximately 10% of the critical micelle concentration or CMC. This type of phase separation commonly occurs during surfactant binding to oppositely charged polyelectrolytes. For CPC, the precipitation is complete, but in the case of DPC, a noticeable fraction of PAHA remains in solution. At very low CPC concentrations (less than 0.1% of the CMC), CPC binding to PAHA is cooperative. The investigated range of concentrations for DPC was too limited to reach a similar conclusion. The results of this study demonstrate that the fate of humic acids will be strongly affected by the presence of low cationic surfactant concentrations in aqueous environmental systems.
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Abstract
Pregnant patients with varicella infections have an increased risk of life threatening pulmonary complications. Prompt diagnosis and aggressive early therapy with acyclovir are important aspects of treating varicella pneumonia. The stress of severe hypoxia usually necessitates delivery by cesarean section. Preoperative evaluation of pulmonary function and choice of anesthetic are critical to intraoperative management. This paper presents the successful treatment of varicella pneumonia in the third trimester of pregnancy with survival of both mother and infant.
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Davis TA, Kaminski MS, Leonard JP, Hsu FJ, Wilkinson M, Zelenetz A, Wahl RL, Kroll S, Coleman M, Goris M, Levy R, Knox SJ. The Radioisotope Contributes Significantly to the Activity of Radioimmunotherapy. Clin Cancer Res 2004; 10:7792-8. [PMID: 15585610 DOI: 10.1158/1078-0432.ccr-04-0756] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE A multicenter, randomized study was undertaken to estimate the single agent activity of Tositumomab and to determine the contribution of radioisotope-labeling with (131)I to activity and toxicity by comparing treatment outcomes for Tositumomab and Iodine I 131 Tositumomab (BEXXAR) to an equivalent total dose of unlabeled Tositumomab. EXPERIMENTAL DESIGN Seventy-eight patients with refractory/relapsed non-Hodgkin's lymphoma were randomized to either unlabeled Tositumomab or Iodine I 131 Tositumomab. Patients progressing after unlabeled Tositumomab could cross over to receive Iodine I 131 Tositumomab. The median follow-up at analysis was 42.6 months (range 1.9 to 71.5 months). RESULTS Responses in the Iodine I 131 Tositumomab versus unlabeled Tositumomab groups: overall response 55% versus 19% (P = 0.002); complete response 33% versus 8% (P = 0.012); median duration of overall response not reached versus 28.1 months (95% confidence interval: 7.6, not reached); median duration of complete response not reached in either arm; and median TTP 6.3 versus 5.5 months (P = 0.031), respectively. Of the patients who had a complete response after initial Iodine I 131 Tositumomab therapy, 71% (10 of 14) continued in complete response at 29.8 to 71.1 months. Two patients who achieved a complete response after unlabeled Tositumomab had ongoing responses at 48.1 to 56.9 months. Nineteen patients received Iodine I 131 Tositumomab crossover therapy. Responses after crossover versus prior response to unlabeled Tositumomab were as follows: complete response rates of 42% versus 0% (P = 0.008); overall response 68% versus 16% (P = 0.002); median durations of overall response 12.6 versus 7.6 months (P = 0.001); and median TTP 12.4 versus 5.5 months (P = 0.01), respectively. Hematologic toxicity was more severe and nonhematologic adverse events were more frequent after Iodine I 131 Tositumomab than after Tositumomab alone. Elevated thyrotropin occurred in 5% of patients. Seroconversion to human antimurine antibody after Iodine I 131 Tositumomab, unlabeled Tositumomab, and Iodine I 131 Tositumomab-crossover was 27%, 19%, and 0%, respectively. CONCLUSIONS Unlabeled Tositumomab showed single agent activity, but in this direct comparison, all of the therapeutic outcome measures were significantly enhanced by the conjugation of (131)I to Tositumomab.
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MESH Headings
- Adult
- Aged
- Aged, 80 and over
- Antibodies, Monoclonal/therapeutic use
- Antigens, CD20/immunology
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Disease-Free Survival
- Drug Resistance, Neoplasm
- Female
- Humans
- Iodine Radioisotopes/therapeutic use
- Lymphoma, B-Cell/drug therapy
- Lymphoma, B-Cell/radiotherapy
- Lymphoma, Non-Hodgkin/drug therapy
- Lymphoma, Non-Hodgkin/radiotherapy
- Male
- Middle Aged
- Neoplasm Recurrence, Local/drug therapy
- Neoplasm Recurrence, Local/radiotherapy
- Radioimmunotherapy
- Remission Induction
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Rollwagen FM, Davis TA, Li YY, Pacheco ND, Zhu XL. Orally administered IL-6 induces elevated intestinal GM-CSF gene expression and splenic CFU-GM. Cytokine 2004; 27:107-12. [PMID: 15271376 DOI: 10.1016/j.cyto.2004.03.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2003] [Revised: 03/16/2004] [Accepted: 03/30/2004] [Indexed: 11/25/2022]
Abstract
Orally administered interleukin (IL)-6 has been shown to be of benefit in eliminating Campylobacter infection and in preventing sepsis following hemorrhage. In related experiments, it was seen that proliferating cells were found in the spleens of untreated mice given IL-6 by oral gavage. Injection of the DNA label, BrdU, showed that significant proliferation began at 4 h and peaked at 24 h in the splenic red pulp of animals given oral IL-6. Mice given saline showed no increase in splenic BrdU uptake. Histological analysis suggested a hematopoietic lineage for these cells. Clonogenic assays performed on spleen cells taken from mice given oral IL-6 revealed that increased granulocyte-macrophage colony forming units (GM-CFU) were present at 24 h post-IL-6 administration. No increase in GM colonies occurred in mice fed IL-3, granulocyte-colony stimulating factor (G-CSF) or granulocyte-macrophage (GM)-CSF. RT-PCR analysis of intestinal mRNA from treated mice revealed that GM-CSF mRNA was elevated at 4 h after oral IL-6 administration, but not in mice fed other cytokines. It is suggested that oral administration of IL-6 induces both proliferation and a brief elevation of GM-CFU in the hematopoietic spleens of mice. This increase appears to be the result of increased GM-CSF mRNA production in the intestines of mice fed IL-6.
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Ramsay TG, Bush JA, McMurtry JP, Thivierge MC, Davis TA. Peripheral leptin administration alters hormone and metabolite levels in the young pig. Comp Biochem Physiol A Mol Integr Physiol 2004; 138:17-25. [PMID: 15165566 DOI: 10.1016/j.cbpb.2004.02.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2003] [Revised: 01/07/2004] [Accepted: 02/10/2004] [Indexed: 10/26/2022]
Abstract
The present study was conducted to determine if peripheral leptin administration can alter GH secretion or feed intake in young pigs. Six, 6 kg female pigs were fasted overnight and randomly chosen to receive porcine recombinant leptin or saline injections in a crossover design. Three leptin dosages were tested over a 10 day period, 100, 200 or 500 microg/kg body mass (L100, L200 or L500). Leptin was administered in 0.2% bovine serum albumin as a bolus injection into the carotid artery. Blood samples were obtained from the jugular vein over a 24 h period. Leptin delayed feeding in pigs treated with L200 and L500 (P<0.05), while reducing overall intake in pigs treated with L100 (P<0.05). L200 or L500 depressed blood glucose (P<0.05). Plasma insulin levels were elevated by feeding in control animals, while insulin levels were depressed in pigs treated with L200 or L500 (P<0.05). L200 elevated plasma growth hormone (P<0.05) with three peaks apparent at 5, 8, and 13 h post injection. The ability for a single injection of leptin to produce significant changes in hormone and metabolite levels suggests that this peptide has a role in regulation of peripheral metabolism.
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Davis TA, Volesky B, Mucci A. A review of the biochemistry of heavy metal biosorption by brown algae. WATER RESEARCH 2003; 37:4311-30. [PMID: 14511701 DOI: 10.1016/s0043-1354(03)00293-8] [Citation(s) in RCA: 941] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The passive removal of toxic heavy metals such as Cd(2+), Cu(2+), Zn(2+), Pb(2+), Cr(3+), and Hg(2+) by inexpensive biomaterials, termed biosorption, requires that the substrate displays high metal uptake and selectivity, as well as suitable mechanical properties for applied remediation scenarios. In recent years, many low-cost sorbents have been investigated, but the brown algae have since proven to be the most effective and promising substrates. It is their basic biochemical constitution that is responsible for this enhanced performance among biomaterials. More specifically, it is the properties of cell wall constituents, such as alginate and fucoidan, which are chiefly responsible for heavy metal chelation. In this comprehensive review, the emphasis is on outlining the biochemical properties of the brown algae that set them apart from other algal biosorbents. A detailed description of the macromolecular conformation of the alginate biopolymer is offered in order to explain the heavy metal selectivity displayed by the brown algae. The role of cellular structure, storage polysaccharides, cell wall and extracellular polysaccharides is evaluated in terms of their potential for metal sequestration. Binding mechanisms are discussed, including the key functional groups involved and the ion-exchange process. Quantification of metal-biomass interactions is fundamental to the evaluation of potential implementation strategies, hence sorption isotherms, ion-exchange constants, as well as models used to characterize algal biosorption are reviewed. The sorption behavior (i.e., capacity, affinity) of brown algae with various heavy metals is summarized and their relative performance is evaluated.
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Davis TA, Llanes F, Volesky B, Diaz-Pulido G, McCook L, Mucci A. 1H-NMR study of Na alginates extracted from Sargassum spp. in relation to metal biosorption. Appl Biochem Biotechnol 2003; 110:75-90. [PMID: 14515023 DOI: 10.1385/abab:110:2:75] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2001] [Revised: 02/01/2003] [Accepted: 02/01/2003] [Indexed: 11/11/2022]
Abstract
The use of a number of species of marine brown algae in the implementation of bioremediation strategies for toxic heavy metals is being considered and evaluated. The biosorption capacity of these algae for heavy metals resides mainly in a group of linear polysaccharides known as alginates that occur as a gel in the algal thallus. The potential for selective metal binding by the biomass of two species of Sargassum was evaluated by 1H-NMR (nuclear magnetic resonance) following a high temperature, alkaline extraction and purification of their alginate polysaccharide. The alkaline extraction protocol applied to Sargassum fluitans and Sargassum siliquosum yielded alginate samples of low viscosity, suitable for direct acquisition of well-resolved spectra. Estimates of both the ratio of beta-D-mannopyranuronosyl (M) and alpha-L-gulopyranuronosyl (G) residues along the polymer chain and the frequencies of occurrence of diad uronic acid residue pairs were obtained. Guluronic acid (G) was the major component in all extracts and the GG diads accounted for more than 49% of the polymer diads. Whereas the performance of Sargassum spp. in the metal biosorption process is a function of both its alginate content and composition, the occurrence of "G-blocks" in both purified alginates and in the raw brown seaweed is critical because it results in a well-established selectivity for divalent ions, potentially increasing the commercial effectiveness of targeted biosorption as a means of remediation.
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Phan GQ, Yang JC, Sherry RM, Hwu P, Topalian SL, Schwartzentruber DJ, Restifo NP, Haworth LR, Seipp CA, Freezer LJ, Morton KE, Mavroukakis SA, Duray PH, Steinberg SM, Allison JP, Davis TA, Rosenberg SA. Cancer regression and autoimmunity induced by cytotoxic T lymphocyte-associated antigen 4 blockade in patients with metastatic melanoma. Proc Natl Acad Sci U S A 2003; 100:8372-7. [PMID: 12826605 PMCID: PMC166236 DOI: 10.1073/pnas.1533209100] [Citation(s) in RCA: 1169] [Impact Index Per Article: 55.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) is a critical immunoregulatory molecule (expressed on activated T cells and a subset of regulatory T cells) capable of down-regulating T cell activation. Blockade of CTLA-4 has been shown in animal models to improve the effectiveness of cancer immunotherapy. We thus treated 14 patients with metastatic melanoma by using serial i.v. administration of a fully human anti-CTLA-4 antibody (MDX-010) in conjunction with s.c. vaccination with two modified HLA-A*0201-restricted peptides from the gp100 melanoma-associated antigen, gp100:209-217(210M) and gp100:280-288(288V). This blockade of CTLA-4 induced grade III/IV autoimmune manifestations in six patients (43%), including dermatitis, enterocolitis, hepatitis, and hypophysitis, and mediated objective cancer regression in three patients (21%; two complete and one partial responses). This study establishes CTLA-4 as an important molecule regulating tolerance to "self" antigens in humans and suggests a role for CTLA-4 blockade in breaking tolerance to human cancer antigens for cancer immunotherapy.
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MESH Headings
- Adult
- Antibodies, Monoclonal/adverse effects
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Neoplasm/adverse effects
- Antibodies, Neoplasm/immunology
- Antibodies, Neoplasm/therapeutic use
- Antigens, CD
- Antigens, Differentiation/immunology
- Antigens, Differentiation/physiology
- Antigens, Neoplasm/administration & dosage
- Antigens, Neoplasm/immunology
- Autoimmune Diseases/etiology
- Autoimmune Diseases/immunology
- Autoimmune Diseases/pathology
- CTLA-4 Antigen
- Colitis/etiology
- Colitis/immunology
- Colitis/pathology
- Dermatitis/etiology
- Dermatitis/immunology
- Dermatitis/pathology
- Female
- HLA-A2 Antigen/immunology
- Hepatitis, Autoimmune/etiology
- Hepatitis, Autoimmune/immunology
- Hepatitis, Autoimmune/pathology
- Humans
- Immune Tolerance/immunology
- Immunotherapy
- Injections, Intravenous
- Injections, Subcutaneous
- Lymphocyte Activation
- Male
- Melanoma/immunology
- Melanoma/therapy
- Membrane Glycoproteins/chemistry
- Membrane Glycoproteins/immunology
- Middle Aged
- Neoplasm Metastasis
- Neoplasm Proteins/chemistry
- Neoplasm Proteins/immunology
- Peptide Fragments/administration & dosage
- Peptide Fragments/immunology
- Peptides
- Salvage Therapy
- T-Lymphocyte Subsets/immunology
- T-Lymphocytes, Cytotoxic/immunology
- Vaccination
- Vitiligo/etiology
- Vitiligo/immunology
- Vitiligo/pathology
- gp100 Melanoma Antigen
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119
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Friis AK, Davis TA, Figueira MM, Paquette J, Mucci A. Influence of Bacillus subtilis cell walls and EDTA on calcite dissolution rates and crystal surface features. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2003; 37:2376-2382. [PMID: 12831020 DOI: 10.1021/es026171g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This study investigates the influence of EDTA and the Gram-positive cell walls of Bacillus subtilis on the dissolution rates and development of morphological features on the calcite [1014] surface. The calcite dissolution rates are compared at equivalent saturation indicies (SI) and relative to its dissolution behavior in distilled water (DW). Results indicate that the presence of metabolically inactive B. subtilis does not affect the dissolution rates significantly. Apparent increases in dissolution rates in the presence of the dead bacterial cells can be accounted for by a decrease of the saturation state of the solution with respect to calcite resulting from bonding of dissolved Ca2+ by functional groups on the cell walls. In contrast, the addition of EDTA to the experimental solutions results in a distinct increase in dissolution rates relative to those measured in DW and the bacterial cell suspensions. These results are partly explained by the 6.5-8 orders of magnitude greater stability of the Ca-EDTA complex relative to the Ca-B. subtilis complexes as well as its free diffusion to and direct attack of the calcite surface. Atomic force microscopy images of the [1014] surface of calcite crystals exposed to our experimental solutions reveal the development of dissolution pits with different morphologies according to the nature and concentration of the ligand. Highly anisotropic dissolution pits develop in the early stages of the dissolution reaction at low B. subtilis concentrations (0.004 mM functional group sites) and in DW. In contrast, at high functional group concentrations (4.0 mM EDTA or equivalent B. subtilis functional group sites), dissolution pits are more isotropic. These results suggest that the mechanism of calcite dissolution is modified by the presence of high concentrations of organic ligands. Since all the pits that developed on the calcite surfaces display some degree of anisotropy and dissolution rates are strongly SI dependent, the rate-limiting step is most likely a surface reaction for all systems investigated in this study. Results of this study emphasize the importance of solution chemistry and speciation in determining calcite reaction rates and give a more accurate and thermodynamically sound representation of dead bacterial cell wall-mineral interactions. In studies of natural aquatic systems, the presence of organic ligands is most often ignored in speciation calculations. This study clearly demonstrates that this oversight may lead to an overestimation of the saturation state of the solutions with respect to calcite and thermodynamic inconsistencies.
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120
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Davis TA, Llanes F, Volesky B, Mucci A. Metal selectivity of Sargassum spp. and their alginates in relation to their alpha-L-guluronic acid content and conformation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2003; 37:261-7. [PMID: 12564896 DOI: 10.1021/es025781d] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The discovery of a consistent and unusual enrichment in homopolymeric alpha-L-guluronic acid G-blocks in alginates extracted from a suite of Sargassum brown algae is described in this study. 1H NMR spectroscopy was used to characterize these alginates which display homopolymeric guluronic acid block (G-block) frequency values (F(GG)) between 0.37 and 0.81. The presence of these G-blocks results in an enhanced selectivity for cadmium or calcium relative to monovalent ions such as sodium and the proton as well as smaller divalent ions such as magnesium. Results of competitive exchange experiments for the Cd-Ca-alginate system yield selectivity coefficient, K*(Cd)Ca, values between 0.43 +/- 0.10 and 1.32 +/- 0.02 for a range in F(GG) of 0.23 to 0.81. In contrast to the Cd-Ca-alginate system, the Mg-Ca-alginate and Mg-Cd-alginate systems yielded maximum values of K*(Mg)Ca (18.0 +/- 1.4) and K*(Mg)Cd (16.0 +/- 0.9) for the alginates extracted from Sargassum fluitans (F(GG) = 0.81; Cuba) and Sargassum thunbergii (F(GG) = 0.75; Korea), respectively. Selectivity studies with mixed-metal pair alginate systems highlight the importance of the specific macromolecular conformation of the alginate polymer in determining metal binding behavior in multiple-metal systems. Furthermore, they demonstrate the importance of the conformation of the alginate as it occurs within the tissue of Sargassum in determining the metal binding behavior of this algal biosorbent. The unique composition of the alginates present in species of Sargassum may represent a distinct advantage over other brown algal species when considering their implementation for the strategic removal of toxic heavy metals from contaminated and industrial wastewaters.
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121
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Li J, Davis TA, Matthews MA. Supercritical Fluid Extraction of 1,2,4-Trichlorobenzene from DOE Job Control Wastes. SEP SCI TECHNOL 2003. [DOI: 10.1081/ss-120022582] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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122
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Chute JP, Saini AA, Chute DJ, Wells MR, Clark WB, Harlan DM, Park J, Stull MK, Civin C, Davis TA. Ex vivo culture with human brain endothelial cells increases the SCID-repopulating capacity of adult human bone marrow. Blood 2002; 100:4433-9. [PMID: 12393435 DOI: 10.1182/blood-2002-04-1238] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Adult human bone marrow (ABM) is an important source of hematopoietic stem cells for transplantation in the treatment of malignant and nonmalignant diseases. However, in contrast to the recent progress that has been achieved with umbilical cord blood, methods to expand ABM stem cells for therapeutic applications have been disappointing. In this study, we describe a novel culture method that uses human brain endothelial cells (HUBECs) and that supports the quantitative expansion of the most primitive measurable cell within the adult bone marrow compartment, the nonobese diabetic/severe combined immunodeficient (NOD/SCID) repopulating cell (SRC). Coculture of human ABM CD34(+) cells with brain endothelial cells for 7 days supported a 5.4-fold increase in CD34(+) cells, induced more than 95% of the CD34(+)CD38(-) subset to enter cell division, and produced progeny that engrafted NOD/SCID mice at significantly higher rates than fresh ABM CD34(+) cells. Using a limiting dilution analysis, we found the frequency of SRCs within fresh ABM CD34(+) cells to be 1 in 9.9 x 10(5) cells. Following HUBEC culture, the estimated frequency of SRCs increased to 1 in 2.4 x 10(5) cells. All mice that received transplants of HUBEC-cultured cells showed B-lymphoid and myeloid differentiation, indicating that a primitive hematopoietic cell was preserved during culture. Noncontact HUBEC cultures also maintained SRCs at a level comparable to contact HUBEC cultures, suggesting that cell-to-cell contact was not required. These data demonstrate that human brain endothelial cells possess a unique hematopoietic activity that increases the repopulating capacity of adult human bone marrow.
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123
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Jazayeri A, Davis TA, Contreras DN. Diagnosis and management of abdominal pregnancy. A case report. THE JOURNAL OF REPRODUCTIVE MEDICINE 2002; 47:1047-9. [PMID: 12516328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
BACKGROUND Abdominal pregnancy is a rare obstetric emergency, occurring in 1 in 10,000 pregnancies. CASE An 18-year-old woman, gravida 3, para 1, presented for evaluation of an abnormal level of maternal serum alpha-fetoprotein. Transabdominal ultrasound examination revealed absence of amniotic fluid with limited imaging ability. Transabdominal amnioinfusion was done to better visualize the fetus. A small uterus was seen in the pelvis, and an abdominal pregnancy was identified with the placenta attached anteriorly over the right pelvic sidewalls. After delivery of the fetus, the placenta was left in situ. The patient recovered postoperatively and was doing well a year after the procedure. A 12 x 10-cm mass remains over the right pelvic sidewall without detectable Doppler blood flow. CONCLUSION State-of-the-art imaging and prenatal diagnostic techniques allowed correct diagnosis, adequate preparation and optimal management of this dangerous condition.
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124
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Diamond LE, Byrne GW, Schwarz A, Davis TA, Adams DH, Logan JS. Analysis of the control of the anti-gal immune response in a non-human primate by galactose alpha1-3 galactose trisaccharide-polyethylene glycol conjugate. Transplantation 2002; 73:1780-7. [PMID: 12085001 DOI: 10.1097/00007890-200206150-00014] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND The current limitation to the clinical application of xenotransplantation using pig organs is a rejection process that has been termed delayed xenograft rejection or acute vascular rejection. It is thought that acute vascular rejection may be mediated at least in part by both the continued synthesis, of preexisting, and the induction, posttransplantation, of antibodies against the carbohydrate moiety galalpha1-3gal that is present on glycoproteins and glycolipids of the pig endothelium. The synthesis of these antibodies has proven difficult to control with currently available immunosuppressive agents. METHODS We have synthesized galalpha1-3gal conjugated polyethylene glycol polymers that can bind to anti-galalpha1-3gal antibodies and tested their activity in non-human primates. RESULTS These conjugates when administered to non-human primates can substantially reduce the levels of preexisting and control the induction of anti-galalpha1-3gal antibodies. The level of circulating antibody-secreting cells that make anti-galalpha1-3gal antibodies is also reduced. CONCLUSION These alpha-gal polyethylene glycol conjugates may have the potential to control the anti-gal antibody response in a pig to primate organ transplant setting and may be a useful therapeutic agent in prolonging graft survival.
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125
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Davis TA, Hsu FJ, Caspar CB, van Beckhoven A, Czerwinsk DK, Liles TM, Taidi B, Benike CJ, Engleman EG, Levy R. Idiotype vaccination following ABMT can stimulate specific anti-idiotype immune responses in patients with B-cell lymphoma. Biol Blood Marrow Transplant 2002; 7:517-22. [PMID: 11669219 DOI: 10.1053/bbmt.2001.v7.pm11669219] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Vaccination with the idiotype (Id) protein derived from B-cell malignancies can produce Id-specific immune responses that correlate with improved remission duration and survival rates in patients with follicular non-Hodgkin's lymphoma (NHL). A state of minimal or no residual disease correlates strongly with the laboratory detection of a cellular or humoral immune response. High-dose cytotoxic therapy (HDCT) with autologous stem cell support (autologous bone marrow transplantation [ABMT]) can provide profound cytoreduction of B-cell NHL, but the potential immune suppression associated with myeloablative therapy may compromise a patient's ability to mount a specific immune response. To determine whether patients with NHL could mount detectable immuneresponses following ABMT, Id vaccines were administered at 2 to 12 months following myeloablative therapy to a series of patients with relapsed or resistant B-cell NHL. Two different vaccination strategies produced robust immune responses against KLH in all patients, supporting the capacity of the reconstituted immune system following HDCT to react against a strong antigen. Combining the results from both vaccination strategies, 10 of 12 patients mounted Id-specific humoral or cellular responses. Vaccinations were consistently well tolerated. Of the 12 patients, 7 have experienced prolonged remissions with a follow-up from HDCT ranging from 3 to more than 11 years. Our experience serves to document the ability of the recovering immune system to react against both self and xenotypic antigens and supports the feasibility and safety of antigen-specific vaccination following myeloablative therapy in patients with B-cell NHL.
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MESH Headings
- Acetylmuramyl-Alanyl-Isoglutamine/administration & dosage
- Acetylmuramyl-Alanyl-Isoglutamine/analogs & derivatives
- Adjuvants, Immunologic
- Antibodies, Anti-Idiotypic/biosynthesis
- Antibodies, Anti-Idiotypic/immunology
- Antibodies, Neoplasm/administration & dosage
- Antibodies, Neoplasm/immunology
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Bone Marrow Transplantation/immunology
- Carmustine/administration & dosage
- Combined Modality Therapy
- Cyclophosphamide/administration & dosage
- Dendritic Cells/immunology
- Dendritic Cells/transplantation
- Disease-Free Survival
- Drug Resistance, Neoplasm
- Etoposide/administration & dosage
- Feasibility Studies
- Female
- Follow-Up Studies
- Hemocyanins/administration & dosage
- Humans
- Ifosfamide/administration & dosage
- Immunity, Cellular
- Immunoglobulin Idiotypes/administration & dosage
- Immunoglobulin Idiotypes/immunology
- Lymphocyte Activation
- Lymphoma, B-Cell/drug therapy
- Lymphoma, B-Cell/immunology
- Lymphoma, B-Cell/therapy
- Male
- Polysorbates/administration & dosage
- Receptors, Antigen, B-Cell/immunology
- Safety
- Squalene/administration & dosage
- Squalene/analogs & derivatives
- Transplantation Conditioning
- Transplantation, Autologous
- Treatment Outcome
- Vaccination
- Whole-Body Irradiation
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