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Richard J O'Reilly

Publications and source records attributed to Richard J O'Reilly.

16 recordsLinked to original sources
PubMed2006

[131I]FIAU labeling of genetically transduced, tumor-reactive lymphocytes: cell-level dosimetry and dose-dependent toxicity.

PURPOSE: Donor T cells have been shown to be reactive against and effective in adoptive immunotherapy of Epstein-Barr virus (EBV) lymphomas which develop in some leukemia patients post marrow transplantation. These T cells may be genetically modified by incorporation of a replication-incompetent viral vector (NIT) encoding both an inactive mutant nerve growth factor receptor (LNGFR), as an immunoselectable surface marker, and a herpes simplex virus thymidine kinase (HSV-TK), rendering the cells sensitive to ganciclovir. The current studies are based on the selective HSV-TK-catalyzed trapping (phosphorylation) of the thymidine analog [(131)I]-2'-fluoro-2'-deoxy-1-beta-D-arabinofuransyl-5-iodo-uracil (FIAU) as a means of stably labeling such T cells for in vivo trafficking (including tumor targeting) studies. Because of the radiosensitivity of lymphocytes and the potentially high absorbed dose to the nucleus from intracellular (131)I (even at tracer levels), the nucleus absorbed dose (D ( n )) and dose-dependent immune functionality were evaluated for NIT(+) T cells labeled ex vivo in [(131)I]FIAU-containing medium. METHODS: Based on in vitro kinetic studies of [(131)I]FIAU uptake by NIT(+) T cells, D ( n ) was calculated using an adaptation of the MIRD formalism and the recently published MIRD cellular S factors. Immune cytotoxicity of [(131)I]FIAU-labeled cells was assayed against (51)Cr-labeled target cells [B-lymphoblastoid cells (BLCLs)] in a standard 4-h release assay. RESULTS AND CONCLUSION: At median nuclear absorbed doses up to 830 cGy, a (51)Cr-release assay against BLCLs showed no loss of immune cytotoxicity, thus demonstrating the functional integrity of genetically transduced, tumor-reactive T cells labeled at this dose level for in vivo cell trafficking and tumor targeting studies.

Animals↗
PubMed2005

Intra-thymic/splenic engraftment of human T cells in HLA-DR1 transgenic NOD/scid mice.

A HLA-DR1 transgenic mouse (NOD/scid-DR1) was derived by breeding the existing B10.M/J-[Tg]DR1 mouse with the NOD/scid mouse. The intention was to enhance engraftment of human T cells by providing human class II elements in the tissues. Thymus and spleen fragments from adult NOD/scid-DR1 mice were transplanted under the syngeneic kidney capsules, followed by injection of human cord blood mononuclear cells (CBMNC) into transplanted tissues. FACS analyses showed that human T and B cells were consistently detected in the peripheral blood and spleen, of the chimeric mice. An average of 20% of human cells was found in the spleen and the engrafted thymus/spleen tissues. Furthermore, human cells from these tissues could proliferate with anti-human CD3 antibody and these mice could generate humoral and cellular responses to allogeneic human cells. Cytokines, such as IL-10, GMCSF, IFN-gamma, and TNF-alpha were also detected in the supernatants of the cultured human cells from the chimeric mice, when they were stimulated with allogeneic cells. Therefore, a novel mouse model with functional circulating human T and B cells was established that would facilitate the exploration of vaccine, the disease processes of autoimmunity, HIV infection, and human cancer.

Animals↗
PubMed2005

Improved outcome in HLA-identical sibling hematopoietic stem-cell transplantation for acute myelogenous leukemia predicted by KIR and HLA genotypes.

Inhibitory killer immunoglobulin (Ig)-like receptors (KIRs) recognize HLA-C and -B epitopes on target cells, thereby regulating natural killer (NK) cell activity. In 178 patients receiving T-cell-depleted HLA-identical sibling transplants for acute myelogenous leukemia (AML), chronic myelogenous leukemia (CML), acute lymphoblastic leukemia (ALL), or myelodysplastic syndrome (MDS), analysis of donor KIR genotype with HLA genotype demonstrated that 62.9% of the patients lacked an HLA ligand for donor-inhibitory KIR. Lack of HLA ligand for donor-inhibitory KIR (missing KIR ligand) had no effect on disease-free survival (DFS), overall survival (OS), or relapse in patients receiving transplants for CML and ALL. In patients with AML and MDS, however, there was a significant missing KIR ligand effect on DFS (P = .014; hazard ratio [HR], 0.53; 95% confidence interval [95% CI], 0.28-0.88) and OS (P = .03; HR, 0.53; 95% CI, 0.3-0.93). Incidence of relapse was also lower in patients with AML and MDS who lacked the HLA ligand for donor-inhibitory KIR (P = .04; HR, 0.41; 95% CI, 0.18-0.97). AML and MDS patients lacking 2 HLA ligands for donor-inhibitory KIR had the highest DFS (P = .002) and OS (P = .003). There was no significant contribution of donor-activating KIR to transplantation outcome in these patients. These data indicate that the absence of class I ligand in the recipient for donor-inhibitory KIR can be a prognostic factor for transplantation outcome in HLA-identical sibling transplantation and that the lack of HLA-C or -B ligands for donor-inhibitory KIR can contribute to improved outcomes for patients with AML and MDS.

Algorithms↗
PubMed2005

Rituximab therapy of lymphoma is enhanced by orally administered (1-->3),(1-->4)-D-beta-glucan.

By activating complement, antitumor monoclonal antibodies coat tumor cells with iC3b. beta-glucans, naturally occurring glucose polymers, bind to the lectin domain of the leukocyte receptor CR3, prime it for binding to iC3b, and trigger cytotoxicity of iC3b-coated tumor cells. We studied the combination of the complement-activating antibody rituximab with barley-derived (1-->3),(1-->4)-beta-D-glucan (BG) against CD-20 positive lymphoma xenografts in SCID mice. Growth of established subcutaneous non-Hodgkin's lymphoma (NHL) (Daudi and EBV-derived B-NHL) or Hodgkin's disease (Hs445 and RPMI6666) was significantly suppressed in mice treated with a combination of intravenous rituximab and oral BG, when compared to mice treated with rituximab or BG alone. Survival of mice with disseminated lymphoma was significantly increased in the combination group as compared to other treatment groups. No clinical toxicity was observed. The therapeutic efficacy and lack of toxicity of this combination supports further investigation into its clinical utility.

Administration, Oral↗
PubMed2004

In vitro stimulation with WT1 peptide-loaded Epstein-Barr virus-positive B cells elicits high frequencies of WT1 peptide-specific T cells with in vitro and in vivo tumoricidal activity.

The Wilms tumor protein (WT1) is overexpressed in most acute and chronic leukemias. To develop a practicable, clinically applicable approach for generation of WT1-specific T cells and to comparatively evaluate the immunogenicity of WT1 in normal individuals, we sensitized T cells from 13 HLA-A0201+ and 5 HLA-A2402+ donors with autologous EBV-transformed B cells or cytokine-activated monocytes, loaded with the HLA-A0201-binding WT1 peptides (126-134)RMFPNAPYL or (187-195)SLGEQQYSV or a newly identified HLA-A2402-binding WT1 peptide (301-310)RVPGVAPTL. WT1-specific T cells were regularly generated from each donor. T cells sensitized with peptide-loaded EBV-transformed B cells generated higher numbers of WT1-specific T cells than peptide-loaded cytokine-activated monocytes. Contrary to expectations, the frequencies of WT1 peptide-specific T cells were equivalent to those generated against individual highly immunogenic HLA-A0201-binding EBV peptides. Each of these T-cell lines specifically killed WT1+ leukemias and solid tumors in an HLA-restricted manner but did not lyse autologous or HLA-matched normal CD34+ hematopoietic progenitor cells or reduce their yield of colony-forming unit-granulocyte-macrophage (CFU-GM), burst-forming unit erythroid (BFU-E), or mixed colonies (CFU-mix). Furthermore, WT1 peptide-specific T cells after adoptive transfer into nonobese diabetic-severe combined immunodeficient mice bearing subcutaneous xenografts of WT1+ and WT1- HLA-A0201+ leukemias preferentially accumulated in and induced regressions of WT1+ leukemias that expressed the restricting HLA allele. Such cells are clinically applicable and may prove useful for adoptive cell therapy of WT1+ malignant diseases in humans.

Alleles↗
PubMed2004

Generation of CMV-specific T lymphocytes using protein-spanning pools of pp65-derived overlapping pentadecapeptides for adoptive immunotherapy.

Cell-mediated immunity is essential for control of human cytomegalovirus (HCMV) infection. We used a pool of 138 synthetic overlapping pentadecapeptides overspanning the entire pp65 protein to generate polyclonal CMV-specific T-cell lines from 12 CMV-seropositive donors inheriting different HLA genotypes. Autologous monocyte-derived dendritic cells (DCs) pulsed with this complete pool consistently induced highly specific T cells that selectively recognized 1-3 pentadecapeptides identified by secondary responses to a mapping grid of pentadecapeptide subpools with single overlaps. Responses against peptide-loaded targets sharing single HLA class I or II alleles identified the restricting HLA alleles. HLA-A*0201+ donors consistently responded to pentadecapeptides containing HLA-A*0201-binding epitope(aa495-503)NLVPMVATV. T-cell lines from other donors contained high frequencies of CD4 and/or CD8 T cells selectively reactive against peptides presented by other HLA alleles, including both known epitopes such as (aa341-350)QYDPVAALF (HLA-A*2402) as well as unreported epitopes such as (aa267-275)HERNGFTVL (HLA-B*4001 and B*4002) and (aa513-523)FFWDANDIYRI (HLA-DRB1*1301). These T cells consistently lysed CMV-infected target cells. Thus, this approach fosters expansion and selection of HLA-restricted CMV-pp65-reactive T-cell lines of high specificity that also lyse CMV-infected targets, and from a functional and regulatory perspective, may have advantages for generating virus-specific T cells for adoptive immunotherapy.

Amino Acid Sequence↗
PubMed2004

Increased plasma levels of stromal-derived factor-1 (SDF-1/CXCL12) enhance human thrombopoiesis and mobilize human colony-forming cells (CFC) in NOD/SCID mice.

OBJECTIVE: Stromal-derived factor-1 (SDF-1/CXCL12) is chemotactic for lympho/hematopoietic stem cells. We have previously shown that increasing peripheral blood (PB) levels of SDF-1 with adenovectors expressing human SDF-1 complementary DNA (ad-SDF-1) leads to hematopoietic stem cell mobilization as well as migration of megakaryocytes and thrombocytosis in mice. Herein, we studied the in vivo effects of ad-SDF-1 and of an analogue peptide of SDF-1 (CTCE-0214) on human hematopoiesis in a xenotransplant model. MATERIALS AND METHODS: Sublethally irradiated (300 cGY) NOD/SCID mice transplanted with human cord blood mononuclear cells (CB MNC) were injected with ad-SDF-1 (10(9) plaque forming units, i.v., x 1) or CTCE-0214 (10 mg/kg/dose, i.v. q 24 hours x 7). Effects on megakaryocytopoiesis (CD41+ cells and platelets) as well as stem cell mobilization were monitored. RESULTS: CB MNC in NOD/SCID mice are able to differentiate into CD41+ cells and platelets, peaking at week 9 at a mean of 3.7 x 10(3)/microL. i.v. injection of ad-SDF-1 increased human CD41+ cells by day 4 in PB and was followed by an increase in human platelet production by day 5, with return to baseline by day 30. Human colony-forming cells (CFC) were mobilized from bone marrow to spleen (by day 6-13) and to PB (by day 13). Human CD34+ and CD33+ cells were mobilized by this treatment as well. A novel SDF-1 peptide agonist (CTCE-0214) also mobilized human CFC and enhanced human thrombopoiesis. CONCLUSION: SDF-1 and its analogue may be of clinical value in stimulating platelet recovery after chemo/radiation treatment as well as in stem cell mobilization.

Adenoviridae↗
PubMed2004

Wilms Tumor Gene (WT1) and p53 expression in endometrial carcinomas: a study of 130 cases using a tissue microarray.

OBJECTIVE: With the exception of ovarian serous carcinoma, Wilms tumor suppressor gene (WT1) expression in common gynecologic carcinomas has not been described in detail. We studied a large number of endometrial carcinomas to determine the range of tumors that express WT1; this could have prognostic and therapeutic significance. METHODS: We studied the immunohistochemical expression of WT1 and p53 in 130 primary human endometrial carcinomas of various histological subtypes, grades, and stages using a tissue microarray. The clinical data were retrieved from the medical records. RESULTS: WT1 was expressed in a wide variety of endometrial cancers and was most marked in malignant mixed Mullerian tumors (MMMTs) (70% positive). WT1 expression was significantly correlated with high histological grade, and there was a trend toward a worse clinical outcome for patients whose tumors expressed WT1. An association between expression of WT1 and p53 and between these and outcome was noted in a univariate analysis, but only stage and p53 status remained prognostically significant independent variables. CONCLUSION: WT1 is expressed in appreciable numbers of endometrial cancers, particularly MMMTs. These findings support further investigation of WT1 as a possible therapeutic target in gynecologic malignancies.

Adult↗
PubMed2003

Evasion from NK cell immunity by MHC class I chain-related molecules expressing colon adenocarcinoma.

Evasion of host immune responses is well documented for viruses and may also occur during tumor immunosurveillance. The mechanisms involve alterations in MHC class I expression, Ag processing and presentation, chemokine and cytokine production, and lymphocyte receptor expression. Epithelial tumors overexpress MHC class I chain-related (MIC) molecules, which are ligands for the activating receptor NKG2D on NK and T cells. We report that NK cells from patients with colorectal cancer lack expression of activating NKG2D and chemokine CXCR1 receptors, both of which are internalized. Serum levels of soluble MIC (sMIC) are elevated and are responsible for down-modulation of NKG2D and CXCR1. In contrast, high serum levels of CXC ligands, IL-8, and epithelial-neutrophil-activating peptide (ENA-78) do not down-modulate CXCR1. In vitro, internalization of NKG2D and CXCR1 occurs within 4 and 24 h, respectively, of incubating normal NK cells with sMIC-containing serum. Furthermore, natural cytotoxicity receptor NKp44 and chemokine receptor CCR7 are also down-modulated in IL-2-activated NK cells cocultured in MIC-containing serum-an effect secondary to the down-modulation of NKG2D and not directly caused by physical association with sMIC. The patients' NK cells up-regulate expression of NKG2D, NKp44, CXCR1, and CCR7 when cultured in normal serum or anti-MIC Ab-treated autologous serum. NKG2D(+) but not NKG2D(-) NK cells are tumoricidal in vitro, and in vivo they selectively traffic to the xenografted carcinoma, form immunological synapse with tumor cells, and significantly retard tumor growth in the SCID mice. These results suggest that circulating sMIC in the cancer patients deactivates NK immunity by down-modulating important activating and chemokine receptors.

Adenocarcinoma↗
PubMed2003

Insulin-like growth factor-I enhances lymphoid and myeloid reconstitution after allogeneic bone marrow transplantation.

BACKGROUND: Prolonged immunodeficiency after allogeneic bone marrow transplantation (allo BMT) results in significant morbidity and mortality from infection. Previous studies in murine syngeneic BMT models have demonstrated that posttransplantation insulin-like growth factor (IGF)-I administration could enhance immune reconstitution. METHODS: To analyze the effects of IGF-I on immune reconstitution and graft-versus-host disease (GVHD) after allo BMT, we used murine models for MHC-matched and -mismatched allo BMT. Young (3-month-old) recipient mice received 4 mg/kg per day of human IGF-I from days 14 to 28 by continuous subcutaneous administration. RESULTS: IGF-I administration resulted in increased thymic precursor populations (triple negative-2 and triple negative-3) as determined on day 28 but had no effect on overall thymic cellularity. In the periphery, the numbers of donor-derived splenic CD3+ T cells were increased and these cells had an improved proliferative response to mitogen stimulation. IGF-I treatment also significantly increased the numbers of pro-, pre-, and mature B cells and myeloid cell populations in the spleens of allo BMT recipients on day 28. The administration of IGF-I in combination with interleukin 7 had a remarkable additive effect on B-cell, but not on T-cell, lymphopoiesis. Finally, we tested the effects of IGF-I administration on the development of GVHD in three different MHC-matched and -mismatched models and found no changes in GVHD morbidity and mortality. CONCLUSION: IGF-I administration can enhance lymphoid and myeloid reconstitution after allo BMT without aggravating GVHD.

Animals↗
PubMed2003

Serial in vivo imaging of the targeted migration of human HSV-TK-transduced antigen-specific lymphocytes.

New technologies are needed to characterize the migration, survival, and function of antigen-specific T cells in vivo. Here, we demonstrate that Epstein-Barr virus (EBV)--specific T cells transduced with vectors encoding herpes simplex virus-1 thymidine kinase (HSV-TK) selectively accumulate radiolabeled 2'-fluoro-2'-deoxy-1-beta-D-arabinofuranosyl-5-iodouracil (FIAU). After adoptive transfer, HSV-TK+ T cells labeled in vitro or in vivo with [131I]FIAU or [124I]FIAU can be noninvasively tracked in SCID mice bearing human tumor xenografts by serial images obtained by scintigraphy or positron emission tomography (PET), respectively. These T cells selectively accumulate in EBV+ tumors expressing the T cells' restricting HLA allele but not in EBV- or HLA-mismatched tumors. The concentrations of transduced T cells detected in tumors and tissues are closely correlated with the concentrations of label retained at each site. Radiolabeled transduced T cells retain their capacity to eliminate targeted tumors selectively. This technique for imaging the migration of ex vivo-transduced antigen-specific T cells in vivo is informative, nontoxic, and potentially applicable to humans.

Animals↗
PubMed2002

Killer Ig-like receptor haplotype analysis by gene content: evidence for genomic diversity with a minimum of six basic framework haplotypes, each with multiple subsets.

Killer Ig-like receptor (KIR) genes constitute a multigene family whose genomic diversity is achieved through differences in gene content and allelic polymorphism. KIR haplotypes containing a single activating KIR gene (A-haplotypes), and KIR haplotypes with multiple activating receptor genes (B-haplotypes) have been described. We report the evaluation of KIR gene content in extended families, sibling pairs, and an unrelated Caucasian panel through identification of the presence or absence of 14 KIR genes and 2 pseudogenes. Haplotype definition included subtyping for the expressed and nonexpressed KIR2DL5 variants, for two alleles of pseudogene 3DP1, and for two alleles of 2DS4, including a novel 2DS4 allele, KIR1D. KIR1D appears functionally homologous to the rhesus monkey KIR1D and likely arose as a consequence of a 22 nucleotide deletion in the coding sequence of 2DS4, leading to disruption of Ig-domain 2D and a premature termination codon following the first amino acid in the putative transmembrane domain. Our investigations identified 11 haplotypes within 12 families. From 49 sibling pairs and 17 consanguineous DNA samples, an additional 12 haplotypes were predicted. Our studies support a model for KIR haplotype diversity based on six basic gene compositions. We suggest that the centromeric half of the KIR genomic region is comprised of three major combinations, while the telomeric half can assume a short form with either 2DS4 or KIR1D or a long form with multiple combinations of several stimulatory KIR genes. Additional rare haplotypes can be identified, and may have arisen by gene duplication, intergenic recombination, or deletions.

Alleles↗
PubMed2002

Direct evidence for new T-cell generation by patients after either T-cell-depleted or unmodified allogeneic hematopoietic stem cell transplantations.

Successful allogeneic hematopoietic stem cell transplantation (HSCT) requires reconstitution of normal T-cell immunity. Recipient thymic activity, biologic features of the allograft, and preparative regimens all contribute to immune reconstitution. We evaluated circulating T-cell phenotypes and T-cell receptor rearrangement excision circles (TRECs) in 331 blood samples from 158 patients who had undergone allogeneic HSCTs. All patients had received myeloablative conditioning regimens and were full donor chimeras in remission. Younger patients exhibited more rapid recovery and higher TRECs (P =.02). Recipients of T-cell-depleted allografts initially had lower TRECs than unmodified allograft recipients (P <.01), but the difference abated beyond 9 months. TREC level disparities did not achieve significance among adults with respect to type of allograft. Measurable, albeit low, TREC values correlated strongly with severe opportunistic infections (P <.01). This finding was most notable during the first 6 months after transplantation, when patients are at greatest risk but before cytofluorography can detect circulating CD45RA(+) T cells. Low TRECs also correlated strongly with extensive chronic graft-versus-host disease (P <.01). Recipients of all ages of either unmodified or T-cell-depleted allografts therefore actively generate new T cells. This generation is most notable among adult recipients of T-cell-depleted allografts, most of whom had also received antithymocyte globulin for rejection prophylaxis. Low TREC values are significantly associated with morbidity and mortality after transplantation. T-cell neogenesis, appropriate to age but delayed in adult recipients of T-cell-depleted allografts, justifies interventions to hasten this process and to stimulate desirable cellular immune responses.

Adolescent↗
PubMed2002

Quantitation, selection, and functional characterization of Epstein-Barr virus-specific and alloreactive T cells detected by intracellular interferon-gamma production and growth of cytotoxic precursors.

Techniques for the quantitation of virus-specific and alloantigen-reactive T cells vary in their measurement of clinically relevant T-cell effector populations, their sensitivity and quantitative accuracy, and the time required to obtain measurable results. We compared frequencies of Epstein-Barr virus (EBV)-specific and major alloantigen-reactive T cells as measured by flow cytometric analysis of responding T cells producing intracellular interferon-gamma (IFN-gamma) and by limiting-dilution analysis (LDA) of cytotoxic T-cell precursors (CTLp) at sequential time points during the generation of EBV-specific T-cell lines. The expansion of EBV-specific T lymphocytes and the depletion of alloreactive T cells in cultures of T cells sensitized with autologous EBV-transformed targets followed similar kinetics when measured by either method. Frequencies of EBV- specific T cells generating intracellular IFN-gamma exceeded by 25- to 90-fold the frequencies of responding CTLp at each stage of expansion, whereas the frequencies of alloreactive T cells generating intracellular IFN-gamma exceeded by 30- to 220-fold those detected by LDA. The assay that quantitated T cells producing IFN-gamma yielded more reproducible and precise results than LDA. Furthermore, frequencies detected by the enumeration of T cells responding to immunodominant EBNA 3a and EBNA 3c peptides by IFN-gamma production or their capacity to bind peptide-HLA tetramers were strikingly similar and represented significant fractions of T cells generating IFN-gamma in response to autologous EBV B lymphoblastoid cell line. Functional analysis of responding viable T cells, fractionated on the basis of their secretion of IFN-gamma, demonstrated that EBV-specific and alloantigen cytotoxic T cells were predominantly or exclusively detected in the CD8(+)IFN-gamma(+) fraction of T cells. Strikingly, the CD4(+)IFN-gamma(+) cell fractions were not cytotoxic against EBV-transformed or allogeneic targets.

Biomarkers↗
PubMed1989

Effects of recombinant human granulocyte colony-stimulating factor on neutropenia in patients with congenital agranulocytosis.

Congenital agranulocytosis is a disorder characterized by severe neutropenia and a profound deficiency of identifiable neutrophil progenitors in bone marrow. In an attempt to stimulate neutrophil production and thereby reduce the morbidity and mortality associated with this disease, we administered recombinant human granulocyte colony-stimulating factor (rhG-CSF) in doses of 3 to 60 micrograms per kilogram of body weight per day to five patients with congenital agranulocytosis. In all five patients, an increase in the number of neutrophils was noted eight to nine days after the initiation of the effective dosage (the dose at which the neutrophil count reached 1000 cells per microliter or more and the bone marrow showed granulocyte maturation beyond the myelocyte stage). The absolute neutrophil counts rose from less than 100 to between 1300 and 9500 cells per microliter. Marrow aspirates obtained after 14 days at the effective dosage showed maturation to the mature neutrophil stage. The side effects that were observed were medullary pain, splenomegaly, and an elevation of levels of leukocyte alkaline phosphatase. All five patients have had sustained neutrophil counts of 1000 cells per microliter or more for 9 to 13 months while receiving subcutaneous maintenance therapy. Preexisting chronic infections have resolved clinically, and the number of new infectious episodes and the requirement for intravenous antibiotics have decreased. We conclude that treatment with rhG-CSF can lead to a large increase in the numbers of functional neutrophils in patients with congenital agranulocytosis.

Adult↗