A phase I study was performed to determine the safety and tolerability of injecting autologous CD34؉ cells into five patients with liver insufficiency. The study was based on the hypothesis that the CD34 ؉ cell population in granulocyte colony-stimulating factor (G-CSF)-mobilized blood contains a subpopulation of cells with the potential for regenerating damaged tissue. We separated a candidate CD34؉ stem cell population from the majority of the CD34 ؉ cells (99%) by adherence to tissue culture plastic.
The adherent and nonadherent CD34؉ cells were distinct in morphology, immunophenotype, and gene expression profile. Reverse transcription-polymerase chain reactionbased gene expression analysis indicated that the adherent CD34؉ cells had the potential to express determinants consistent with liver, pancreas, heart, muscle, and nerve cell differentiation as well as hematopoiesis. Overall, the characteristics of the adherent CD34 ؉ cells identify them as a separate putative stem/progenitor cell population. In culture, they produced a population of cells exhibiting diverse morphologies and expressing genes corresponding to multiple tissue types. Encouraged by this evidence that the CD34 ؉ cell population contains cells with the potential to form hepatocyte-like cells, we gave G-CSF to five patients with liver insufficiency to mobilize their stem cells for collection by leukapheresis. Between 1 ؋ 10 6 and 2 ؋ 10 8 CD34 ؉ cells were injected into the portal vein (three patients) or hepatic artery (two patients). No complications or specific side effects related to the procedure were observed. Three of the five patients showed improvement in serum bilirubin and four of five in serum albumin. These observations warrant further clinical trials.
A B S R A C T The effect of efferent, parasympathetic stimulation upon pancreatic polypeptide (PP) secretion was studied in three ways: (a) Plasma PP concentrations increased in response to insulin-induced hypoglycemia in both normal subjects, from 11 pM (9.5-12.5) to 136 pM (118-147), n = 8 (median and interquartile range) and in duodenal ulcer patients, from 33 pM (21-52) to 213 pM (157-233), n = 7. The PP response to hypoglycemia was diminished by atropine in normal subjects (P <
It is safe to mobilize, expand, and reinfuse autologous CD34+ cells in patients with ALC. The clinical and biochemical improvement in the study group is encouraging and warrants further clinical trials.
Treatment with CD34+ hematopoietic stem/progenitor cells has been shown to improve functional recovery in nonhuman models of ischemic stroke via promotion of angiogenesis and neurogenesis. We aimed to determine the safety and feasibility of treatment with CD34+ cells delivered intra-arterially in patients with acute ischemic stroke. This was the first study in human subjects. We performed a prospective, nonrandomized, open-label, phase I study of autologous, immunoselected CD34+ stem/progenitor cell therapy in patients presenting within 7 days of onset with severe anterior circulation ischemic stroke (National Institutes of Health Stroke Scale [NIHSS] score≥8). CD34+ cells were collected from the bone marrow of the subjects before being delivered by catheter angiography into the ipsilesional middle cerebral artery. Eighty-two patients with severe anterior circulation ischemic stroke were screened, of whom five proceeded to treatment. The common reasons for exclusion were age>80 years (n=19); medical instability (n=17), and significant carotid stenosis (n=13). The procedure was well tolerated in all patients, and no significant treatment-related adverse effects occurred. All patients showed improvements in clinical functional scores (Modified Rankin Score and NIHSS score) and reductions in lesion volume during a 6-month follow-up period. Autologous CD34+ selected stem/progenitor cell therapy delivered intra-arterially into the infarct territory can be achieved safely in patients with acute ischemic stroke. Future studies that address eligibility criteria, dosage, delivery site, and timing and that use surrogate imaging markers of outcome are desirable before larger scale clinical trials.
In pancreatic islets a peptide corresponding to the C-terminal tetrapeptide amide of cholecystokinin and gastrin, Trp-Met-Asp-Phe-NH2, is present in nerve terminals. This tetrapeptide amide is uniquely potent as a releaser of insulin and the other islet hormones, whereas larger cholecystokinins and gastrins as well as tetrapeptide analogues are considerably less potent. We suggest that neural release of the tetrapeptide amide is implicated in regulation of pancreatic hormone secretion.
Evidence is growing in support of the role of stem cells as an attractive alternative in treatment of liver diseases. Recently, we have demonstrated the feasibility and safety of infusing CD34(+) adult stem cells; this was performed on five patients with chronic liver disease. Here, we present the results of long-term follow-up of these patients. Between 1 x 10(6) and 2 x 10(8) CD34(+) cells were isolated and injected into the portal vein or hepatic artery. The patients were monitored for side effects, toxicity and changes in clinical, haematological and biochemical parameters; they were followed up for 12-18 months. All patients tolerated the treatment protocol well without any complications or side effects related to the procedure, also there were no side effects noted on long-term follow-up. Four patients showed an initial improvement in serum bilirubin level, which was maintained for up to 6 months. There was marginal increase in serum bilirubin in three of the patients at 12 months, while the fourth patient's serum bilirubin increased only at 18 months post-infusion. Computed tomography scan and serum alpha-foetoprotein monitoring showed absence of focal lesions. The study indicated that the stem cell product used was safe in the short and over long term, by absence of tumour formation. The investigation also illustrated that the beneficial effect seemed to last for around 12 months. This trial shows that stem cell therapy may have potential as a possible future therapeutic protocol in liver regeneration.
Sera from 17 patients with primary and secondary liver tumors who had been administered oncolytic adenovirus (Ad) mutant Addl1520 were analyzed for anti-Ad neutralization titers and antibodies to the Ad major capsid proteins hexon, penton base (Pb), and fiber. The antibodies recognized mainly conformational epitopes in hexon and both linear and conformational epitopes in Pb and fiber. Pb-specific antibodies were isolated from serum samples that had been obtained prior to and during the course of the treatment of four of these patients. We found that the Pb antibodies had a significant contribution toward anti-Ad neutralization, and this mainly occurred at the step of virus internalization. The Pb antigenic epitopes were determined by phage biopanning and were mapped to 10 discrete regions, which made up three major immunodominant domains within residues 51 to 120, 193 to 230, and 311 to 408, respectively. One of these domains (residues 311 to 408) overlapped the highly conserved, integrin-binding RGD (Arg-Gly-Asp) motif. The contribution of antibodies directed to RGD and other epitopes in Ad neutralization activity was determined indirectly by using a phage-mediated depletion assay. Our results suggested that circulating RGD antibodies were not prevalent and were poorly neutralizing and that other peptide motifs within residues 51 to 60, 216 to 226, and 311 to 408 in Pb sequence represented major target sites for neutralizing antibodies.
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