Biomedical subjects

Jennifer M Puck

Publications and source records attributed to Jennifer M Puck.

29 records · Page 2Linked to original sources

PubMed2004

Successes and risks of gene therapy in primary immunodeficiencies.

Several primary immunodeficiencies are under consideration for gene therapy approaches because of limitations of current standard treatment. Many primary immunodeficiencies are caused by defects in single genes expressed in blood cells; thus addition of a correct copy of the gene to hematopoietic stem cells (HSCs) can generate immune cells with restored function. HSCs can be removed from a patient, treated outside the body, and reinfused. In the last decade, significant improvements have been made in transferring genes by means of retroviruses to HSCs in vitro, and gene therapy trials for patients with X-linked severe combined immunodeficiency (XSCID) and adenosine deaminase-deficient severe combined immunodeficiency have restored immune competence. Gene therapy is actively being pursued in other immunodeficiency disorders, including chronic granulomatous disease and Wiskott-Aldrich syndrome. However, enthusiasm for the correction of XSCID by means of gene therapy has been tempered by the occurrence of 2 cases of leukemia in gene therapy recipients caused by insertion of the retroviral vector in or near the oncogene LMO2. The likelihood of retroviral insertional mutagenesis was estimated to be very low in the past on the basis of theoretic calculations and the absence of observed malignancies in animal studies and early clinical trials. Emerging new findings on retroviral integration both in the patients with XSCID and experimental animals now indicate that the insertion of retroviral sequences into the genome carries significant risk. Understanding the magnitude of risk is now a priority so that safety can be improved for future gene therapy clinical trials.

Genetic Therapy↗

PubMed2004

Autosomal recessive hyperimmunoglobulin E syndrome: a distinct disease entity.

OBJECTIVE: The autosomal-dominant form of the hyperimmunoglobulin E syndrome (AD-HIES) has been described as a multisystem disorder including immune, skeletal, and dental abnormalities. Variants of AD-HIES are known but not well defined. METHODS: We evaluated 13 human immunodeficiency virus-seronegative patients from six consanguineous families with an autosomal-recessive form of hyperimmunoglobulin E syndrome (AR-HIES) and 68 of their relatives. RESULTS: Persons affected with AR-HIES presented with the classical immunologic findings of hyperimmunoglobulin E syndrome, including recurrent staphylococcal infections of the skin and respiratory tract, eczema, elevated serum immunoglobulin E, and hypereosinophilia. In addition, severe recurrent fungal and viral infections with molluscum contagiosum, herpes zoster, and herpes simplex were noted. Autoimmunity was seen in two patients. Central nervous system sequelae, including hemiplegia, ischemic infarction, and subarachnoid hemorrhages, were common and contributed to high mortality. Notably, patients with AR-HIES did not have skeletal or dental abnormalities and did not develop pneumatoceles, as seen in AD-HIES. In lymphocyte proliferation assays, patients' cells responded poorly to mitogens and failed to proliferate in response to antigens, despite the presence of normal numbers of lymphocyte subpopulations. CONCLUSION: The autosomal-recessive form of hyperimmunoglobulin E syndrome is a primary immunodeficiency with elevated immunoglobulin E, eosinophilia, vasculitis, autoimmunity, central nervous system symptoms, and high mortality. AR-HIES lacks several of the key findings of AD-HIES and therefore represents a different, previously unrecognized disease entity.

Autoimmunity↗

PubMed2004

Perspectives of gene therapy for primary immunodeficiencies.

PURPOSE OF REVIEW: Standard therapies for patients with severe primary immunodeficiencies include bone marrow transplantation and, for adenosine deaminase deficiency, enzyme replacement. In the last decade, gene therapy has been developed as an alternative for these conditions. We summarize the recent advances in gene therapy for primary immunodeficiencies and discuss the unexpected occurrence of leukemia in a gene therapy trial for X-linked severe combined immunodeficiency. RECENT FINDINGS: Eight of 10 infants with X-linked severe combined immunodeficiency who received autologous hematopoietic stem cells transduced with a retroviral vector carrying the IL2RG complementary DNA achieved immune reconstitution. However, the two youngest patients developed leukemic expansions of gene-corrected cells. The first case had proliferation of a gamma delta T cell clone, and the second case had three alpha beta T cell clones derived from a single transduced progenitor. Leukemic cells in both patients aberrantly expressed the LIM domain only-2 transcription factor due to retroviral vector insertions in this locus. After receiving anti-leukemic treatment one patient achieved a lasting remission, but the other relapsed. Four adenosine deaminase deficient severe combined immunodeficiency patients also developed functional immunity after receiving autologous hematopoietic stem cells transduced with the adenosine deaminase gene complementary DNA following submyeloablative chemotherapy. Chronic granulomatous disease, Wiskott-Aldrich syndrome, JAK3 deficiency and RAG2 deficiency are other immunodeficiencies being studied as candidates for gene therapy. SUMMARY: Gene therapy is a promising therapeutic option for some primary immunodeficiencies, especially when cells expressing the correct gene have a selective advantage. More clinical trials with closer patient monitoring are under way to define which patients may benefit from this approach, and strategies are being developed to understand and ultimately reduce the risk of leukemia secondary to retroviral vector insertion.

Adenosine Deaminase↗

PubMed2004

Parallel genotyping of over 10,000 SNPs using a one-primer assay on a high-density oligonucleotide array.

The analysis of single nucleotide polymorphisms (SNPs) is increasingly utilized to investigate the genetic causes of complex human diseases. Here we present a high-throughput genotyping platform that uses a one-primer assay to genotype over 10,000 SNPs per individual on a single oligonucleotide array. This approach uses restriction digestion to fractionate the genome, followed by amplification of a specific fractionated subset of the genome. The resulting reduction in genome complexity enables allele-specific hybridization to the array. The selection of SNPs was primarily determined by computer-predicted lengths of restriction fragments containing the SNPs, and was further driven by strict empirical measurements of accuracy, reproducibility, and average call rate, which we estimate to be >99.5%, >99.9%, and>95%, respectively [corrected]. With average heterozygosity of 0.38 and genome scan resolution of 0.31 cM, the SNP array is a viable alternative to panels of microsatellites (STRs). As a demonstration of the utility of the genotyping platform in whole-genome scans, we have replicated and refined a linkage region on chromosome 2p for chronic mucocutaneous candidiasis and thyroid disease, previously identified using a panel of microsatellite (STR) markers.

Alleles↗

PubMed2003

Immune disorders caused by defects in the caspase cascade.

In the immune system, lymphocyte activation by antigen is followed by cell proliferation and induction of effector functions. Subsequently, physiologic cell-death signals are induced, resulting in removal of expanded effector-cell populations, to maintain homeostasis. Caspases are intracellular participants in both activation responses and cell death by apoptosis. Targets of caspases include inflammatory activators and also other members of the caspase family that mediate apoptosis. Caspase-8 and caspase-10 participate in the protease cascade following cell surface CD95 engagement by its ligand. Humans with defects in these caspases were initially evaluated for the autoimmune lymphoproliferative syndrome because of their spleen and lymph node enlargement. Although both caspase-8- and caspase-10-deficient individuals had impaired apoptosis, those with caspase-8 deficiency, who also had immunodeficiency, had additional defects in activation of lymphocytes and natural killer cells. These disorders help to define the importance and specificity of the caspase proteases in intracellular signaling pathways.

Animals↗

PubMed2003

Immunodeficiency disorders.

Hematological complications occur frequently in patients with both primary and secondary immunodeficiency disorders. Anemia, thrombocytopenia or leukopenias may bring these individuals to the attention of hematologists. Conversely, evidence suggesting a lymphoproliferative disorder may be the cause for referral. This session will provide an update on the diagnosis and treatment of immunodeficiency diseases ranging from isolated defects in antibody production to the severe combined immunodeficiencies (SCID). Immunodeficiency diseases have traditionally been defined as defects in the development and function of T and B cells, the primary effector cells of specific cellular and humoral immunity. However, it has become increasingly evident that innate immune mechanisms contribute greatly to host defense, either through acting alone or by enhancing specific T and B cell responses. In Section I, Dr. Lewis Lanier reviews the burgeoning information on the extensive families of activating and inhibitory immunoreceptors that are expressed on NK cells, dendritic cells, T and B cells, and phagocytic cells. He provides an overview on the biological functions of these receptors in host defense. In Section II, Dr. Mary Ellen Conley defines the spectrum of antibody deficiency disorders, the most frequently occurring types of primary immunodeficiencies. She covers the different defects in B-cell development and function that lead to antibody deficiencies, and includes diagnosis and therapy of these disorders. In Section III, Dr. Jennifer Puck discusses the diagnosis and treatment of the different types of SCID. She describes the genetic basis for SCID, and the benefits, pitfalls, and complications of gene therapy and bone marrow transplantation in SCID patients.

Humans↗

PubMed2002

Retroviral transduction of IL2RG into CD34(+) cells from X-linked severe combined immunodeficiency patients permits human T- and B-cell development in sheep chimeras.

X-linked severe combined immunodeficiency (XSCID) is caused by mutations of the common gamma chain of cytokine receptors, gamma(c). Because bone marrow transplantation (BMT) for XSCID does not provide complete immune reconstitution for many patients and because of the natural selective advantage conferred on lymphoid progenitors by the expression of normal gamma(c), XSCID is a good candidate disease for therapeutic retroviral gene transfer to hematopoietic stem cells. We studied XSCID patients who have persistent defects in B-cell and/or combined B- and T-cell function despite having received T cell-depleted haploidentical BMT. We compared transduction of autologous B-cell lines and granulocyte colony-stimulating factor-mobilized peripheral CD34(+) cells from these patients using an MFGS retrovirus vector containing the gamma(c) gene IL2RG pseudotyped with amphotropic, gibbon ape leukemia virus, or RD114 envelopes. Transduced B-cell lines and peripheral CD34(+) cells demonstrated provirus integration and new cell-surface gamma(c) expression. The chimeric sheep model was exploited to test development of XSCID CD34(+) cells into mature myeloid and lymphoid lineages. Transduced and untransduced XSCID CD34(+) cells injected into developing sheep fetuses gave rise to myeloid cells. However, only transduced gamma progenitors from XSCID patients developed into T and B cells. These results suggest that gene transfer to autologous peripheral CD34(+) cells using MFGS-gc retrovirus may benefit XSCID patients with persistent T- and B-cell deficits despite prior BMT.

Animals↗

PubMed2002

Drug selection with paclitaxel restores expression of linked IL-2 receptor gamma -chain and multidrug resistance (MDR1) transgenes in canine bone marrow.

Unstable expression of transferred genes is a major obstacle to successful gene therapy of hematopoietic diseases. We have investigated in a canine large-animal model whether expression of transduced genes can be recovered in vivo. Mixed-breed dogs had undergone autologous bone marrow transplantation (BMT) with stem cell factor and granulocyte-colony-stimulating factor-mobilized retrovirally marked hematopoietic cells. The bicistronic retroviral vector construct allowed for coexpression of MDR1 and human IL-2 receptor common gamma-chain cDNAs. The latter gene is deficient in X-linked severe combined immunodeficiency. After initial high-level expression, P-glycoprotein and the gamma-chain were undetectable in blood and bone marrow 17 months post-BMT. Six months later, one dog was treated i.v. with 125 mg/m2 paclitaxel. Three administrations restored expression of the two linked genes to high levels in blood and bone marrow. Two dogs treated with higher paclitaxel doses died from myelosuppression after the first administration. As determined by flow cytometry, both genes were expressed in granulocytes, monocytes, and lymphocytes of the surviving animal. PCR analysis of DNA from peripheral blood confirmed that the retroviral cDNA was increased after paclitaxel treatment, suggesting enrichment of transduced cells. P-glycoprotein was detectable for more than 1 year after cessation of paclitaxel. Repeated analyses of blood and bone marrow aspirates gave no indication of hematopoietic disturbance after BMT with transduced cells and paclitaxel treatment. In summary, we have shown that with the use of a drug-selectable marker gene, chemotherapy can select for cells that express an otherwise nonselected therapeutic gene in blood and bone marrow.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2002

Hematopoietic stem cell transplantation for severe combined immunodeficiency in the neonatal period leads to superior thymic output and improved survival.

All genetic types of severe combined immunodeficiency (SCID) can be cured by stem cell transplantation from related donors. The survival rate approaches 80%, and most deaths result from opportunistic infections acquired before transplantation. It was hypothesized that the survival rate and kinetics of immune reconstitution would be improved for infants receiving transplants in the neonatal period (first 28 days of life), prior to the development of infections. A 19.2-year retrospective/prospective analysis compared immune function in 21 SCID infants receiving transplants in the neonatal period with that in 70 SCID infants receiving transplants later. Lymphocyte phenotypes, proliferative responses to mitogens, immunoglobulin levels, and T-cell antigen receptor excision circles (TRECs) were measured before transplantation and sequentially after transplantation. Of 21 SCID infants with transplantations in the neonatal period, 20 (95%) survive. Neonates were lymphopenic at birth (1118 +/- 128 lymphocytes per cubic millimeter). Infants receiving transplants early developed higher lymphocyte responses to phytohemagglutinin and higher numbers of CD3(+) and CD45RA(+) T cells in the first 3 years of life than those receiving transplants late (P <.05). TRECs peaked earlier and with higher values (P <.01) in the neonatal transplantations (181 days to 1 year) than in the late transplantations (1 to 3 years). SCID recipients of allogeneic, related hematopoietic stem cells in the neonatal period had higher levels of T-cell reconstitution and thymic output and a higher survival rate than those receiving transplants after 28 days of life. An improved outcome for this otherwise fatal syndrome could be achieved with newborn screening for lymphopenia so that transplantation could be performed under favorable thymopoietic conditions.

Age Factors↗

PubMed2002

Hypo-active variant of IL-2 and associated decreased T cell activation contribute to impaired apoptosis in autoimmune prone MRL mice.

Apoptosis of activated lymphocytes is crucial to the maintenance of immune homeostasis and self-tolerance, as demonstrated by the well-known autoimmune MRL lpr mouse lacking the death receptor Fas. However, even MRL+/+ activated T cells have a resistance to Fas-mediated apoptosis as compared to T cells from the non-autoimmune FVB/N strain. To understand the molecular mechanisms underlying these strain differences, we studied biochemical characteristics of T cells upon activation. Compared to FVB/N T cells, MRL T cells under-expressed procaspase-3 but over-expressed FLIP(L). In addition, up-regulation of Bcl-x(L), IL-2, and CD25 was diminished in MRL cells, suggesting inadequate T cell activation. Upon finding that MRL, like other autoimmune strains NOD and SJL, has a hypo-active variant of the IL-2 gene, we added wild-type murine recombinant (mr)IL-2 during activation. Exogenous mrIL-2 restored MRL apoptosis to the level of FVB/N; in addition, expression of procaspase-3, and FLIP(L), Bcl-x(L) and CD25 was normalized. These results suggest that defective MRL T cell activation, in part due to hypo-active IL-2, underlies the impaired apoptosis of this strain. In addition, the hypo-active variant of IL-2 shared among autoimmune strains may, by causing diminished cell activation and cell death, predispose these strains to develop autoimmune disease.

Amino Acid Sequence↗

PubMed2002

Aberrant T-cell antigen receptor-mediated responses in autoimmune lymphoproliferative syndrome.

Autoimmune Lymphoproliferative Syndrome (ALPS) is a disorder of defective lymphocyte apoptosis due to mutations of the Fas receptor and other molecules in the Fas signaling pathway. In addition to accumulation of CD4(-) CD8(-) double-negative (DN) T cells, many patients display a dysregulated cytokine pattern with dysfunctional T cells, suggesting Fas defects may impact pathways of T-cell activation/differentiation. Here, we report two novel mutations in the Fas receptor resulting in an ALPS phenotype. Utilizing flow cytometry, we found anti-CD3 activated CD4(+) T cells from these patients were incapable of fully upregulating activation markers (CD25, CD69, and CD40L) or producing interferon-gamma and IL-2. Additionally, DN T cells were unable to transduce proximal T-cell antigen receptor signals or produce cytokines. Furthermore, DN T cells overexpressed CD57 and phenotypically resembled end-stage effector cells. As DN T cells were essentially anergic, the clinical manifestations of autoimmunity are more likely to be a consequence of aberrant cytokine secretion within the CD4(+) T-cell subpopulation.

Antigens, CD↗