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L D Notarangelo

Publications and source records attributed to L D Notarangelo.

At least 91 records · Page 5Linked to original sources
PubMed1997

CD70 expression on T-cell subpopulations: study of normal individuals and patients with chronic immune activation.

CD70, the ligand of CD27, is a member of the TNF family, which includes molecules essential in the regulation of lymphocyte growth and survival. It is absent on resting lymphocytes but can be induced in vitro with activating stimuli. To extend information about its expression by different T-cell subpopulations, and its regulation in normal and pathologic conditions, highly purified T-cell subpopulations were studied: CD70 expression depended both on the activating stimulus and on the T-cell subset analyzed. PMA + Ionomycin induced CD70 on the large majority of CD8+ cells, but only on a minority of CD4+ cells (P < 0.002), and among these, preferentially on the CD45R0+ subset compared with the CD45RA+. The presence of CD4+ lymphocytes in cell cultures containing mixtures of T-cell subsets inhibited CD70 expression on CD8+ cells. On the contrary, stimulation with allogeneic cells induced CD70 expression also on CD4+ cells. Moreover, CD70 was found to be expressed by chronically in vivo activated T-cells, in conditions characterized by allogeneic and autoimmune reactions. These data suggest a possible role of CD70 in the pathogenesis of immune dysregulation; interestingly, this role may not be simply restricted to bind to, and signal through, CD27, since cross-linking of CD70 enhances the proliferative response induced by the stimuli used to elicit its expression.

Antigens, CD↗
PubMed1997

Advances in the understanding of cytokine signal transduction: the role of Jaks and STATs in immunoregulation and the pathogenesis of immunodeficiency.

Cytokines are of great importance in the growth and differentiation of hematopoietic and other cells. Moreover, they are also crucial in immunoregulation and in host defense. Although our understanding of the molecular basis of cytokine action is far from complete, recent advances have substantially improved our knowledge of cytokine-dependent signal transduction. The delineation of the structure of cytokine receptors and the signaling pathways they utilize has provided clues as to how the strikingly specific effects of cytokines are achieved. Additionally, the basis of some of the pleiotropic and redundant effects of cytokines has also become clear. The discovery of the Janus family of protein tyrosine kinases (Jaks) and the STATs (signal transducers and activators of transcription) has also provided key insights into the mechanism by which intracellular signals are transduced. The following paradigm has emerged: cytokines induce dimerization of receptor subunits that are constitutively associated with Jaks. This activates the Jaks, which then phosphorylate the receptors. The phosphorylated receptors are bound by SH2-containing proteins, one class of which is the STATs. Activated STATs, then, translocate to the nucleus to effect gene transcription. Though the Jaks do not explain much in terms of specificity in signaling, the function of the STATs does. The discovery of patients with autosomal recessive severe combined immunodeficiency due to mutations of a particular Jak, Jak3, and the phenotype of knockout mice lacking Jak3 and various STATs demonstrate the specific and critical roles of these molecules in the development and function of the immune system.

Adjuvants, Immunologic↗
PubMed1996

In-utero transplantation of parental CD34 haematopoietic progenitor cells in a patient with X-linked severe combined immunodeficiency (SCIDXI).

BACKGROUND: X-linked severe combined immunodeficiency (SCIDXI) is an inherited immune defect which leads to death in infancy from severe infections. The defect is caused by mutations of the IL-2RG gene that encodes for the common gamma chain shared by several cytokine receptors. The disease is characterised by lack of T and NK cells with normal numbers of B cells. SCIDXI can be cured by bone marrow transplantation (BMT) or prevented by abortion after prenatal diagnosis. METHODS: A male fetus was diagnosed as having SCIDXI by molecular, immunophenotypic, and functional analyses. The fetus was injected intraperitoneally under ultrasound guidance with CD34 haematopoietic progenitor cells purified from paternal bone marrow and T-cell depleted by E rosetting. Chimerism analysis was by HLA-DQ alpha typing and gamma-chain staining on cord blood. FINDINGS: A healthy 3.6 kg boy was delivered by caesarean section at 38 weeks of gestation with no clinical or laboratory signs of graft-versus-host disease. Engraftment of donor-derived CD2 cells was found at birth. At 3.5 months of age the infant is well and his T-cell counts and function are normal. INTERPRETATION: In-utero transplantation of haematopoietic progenitor cells allowed immune reconstitution of a fetus with SCIDXI and may be an alternative to elective abortion. Our report should encourage applications of this method to other inherited disorders curable by BMT.

Antigens, CD34↗
PubMed1996

Monocyte function in a severe combined immunodeficient patient with a donor splice site mutation in the Jak3 gene.

Janus kinase-3 (Jak3) is a nonreceptor tyrosine kinase functionally coupled to cytokine receptors which share a "common" gamma chain (gamma c). Mutations in gamma c and Jak3 genes have been identified in X-linked and autosomal severe combined immuno deficiency (SCID), respectively. Jak3 is expressed and activated in myelomonocytic cells. The present study was designed to define the structural alteration responsible for lack of Jak3 in a patient with autosomal SCID and to characterize monocyte function in the absence of this signal transduction element, as well as to establish the whole exon-intron structure. Polymerase chain reaction analysis, performed with primers designed on exon sequences, identified 20 exons spanning approximately 15 kb. These primers, or others designed on the flanking sequences provided in the present report, can be used to amplify the whole gene, allowing the definition of the molecular defects in all cases, including prenatal diagnosis, in which transcript analysis is not possible. On this basis, the deletion transcript found at the homozygous state in patient CM, with both his consanguineous parents being heterozygous for the deletion, was associated with mutation (T to C) of a splice donor site of intron 16 that was also detected in his mother's DNA. Monocytes from Jak3-SCID showed normal cytokine production in response to interleukin-4 (IL-4) (release of IL-1 receptor antagonist) and IL-2 (release of tumor necrosis factor-alpha and IL-8). Lipopolysaccharide-induced cytokine production was also normal and was blocked by IL-4 in Jak3- SCID monocytes. Interferon-gamma induced augmented expression of major histocompatibility class II in Jak3-SCID monocytes. These data indicate that Jak3, expressed and activated in myelomonocytic cells, is dispensable for monocyte differentiation and responsiveness to cytokines that interact with gamma c receptors as well as to other regulatory signals.

Base Sequence↗
PubMed1996

In vitro correction of JAK3-deficient severe combined immunodeficiency by retroviral-mediated gene transduction.

Mutations affecting the expression of the Janus family kinase JAK3 were recently shown to be responsible for autosomal recessive severe combined immunodeficiency (SCID). JAK3-deficient patients present with a clinical phenotype virtually indistinguishable from boys affected by X-linked SCID, a disease caused by genetic defects of the common gamma chain (gamma c) that is a shared component of the receptors for IL-2, IL-4, IL-7, IL-9, and IL-15. The specific interaction of JAK3 and gamma c represents the biochemical basis for the similarities between these two immunodeficiencies. Both forms of SCID are characterized by recurrent, severe infections leading to death in infancy unless successfully treated by allogeneic bone marrow transplantation. Because of the potentially lethal complications associated with allogeneic bone marrow transplantation and the frequent lack of suitable marrow donors, the development of alternative forms of therapy is highly desirable. To this end, we investigated a retroviral-mediated gene correction approach for JAK3-deficiency. A vector carrying a copy of JAK3 cDNA was constructed and used to transduce B cell lines derived from patients with JAK3-deficient SCID. We demonstrate restoration of JAK3 expression and phosphorylation upon IL-2 and IL-4 stimulation. Furthermore, patients' cells transduced with JAK3 acquired the ability to proliferate normally in response to IL-2. These data indicate that the biological defects of JAK3-deficient cells can be efficiently corrected in vitro by retroviral-mediated gene transfer, thus providing the basis for future investigation of gene therapy as treatment for JAK3-deficient SCID.

B-Lymphocytes↗
PubMed1996

Studies of the expression of the Wiskott-Aldrich syndrome protein.

The Wiskott-Aldrich syndrome (WAS) is an X-linked disorder characterized by thrombocytopenia, eczema, disorders in cell-mediated and humoral immunity, and a proclivity to lymphoproliferative disease. The gene responsible encodes a 53-kD proline-rich protein of unknown function (WASP). We produced a FLAG-WASP fusion protein that was used to immunize mice and produce mAbs against WASP. Using monoclonal anti-WASP in Western immunoblots, we have determined that WASP is present in the cytoplasmic but not nuclear fraction of normal human peripheral blood mononuclear cells, in normal human platelets, in T lymphocytes, non-T lymphocytes, and monocytes. The protein is produced in the B cell immunoblastic cell line DS-1, in normal EBV-transformed B cell lines, and in HEL92.1.7, but is barely detectable in MOLT-4 and not detectable in K562. WASP was present in two of four EBV-transformed cell lines from WAS patients. Splenic tissue immunostaining was performed in two patients, and the results correlated with the results of the Western blots. Sequence analysis of WASP cDNA from two patients who produce WASP show mutations causing amino acid substitutions. These studies establish a foundation for further studies aimed at understanding the function of WASP.

Amino Acid Sequence↗
PubMed1996

CD30 cell expression and abnormal soluble CD30 serum accumulation in Omenn's syndrome: evidence for a T helper 2-mediated condition.

Omenn's syndrome (OS) is a severe immunodeficiency, characterized by clinical and laboratory features reminiscent of a T helper type-2 (Th2) response. CD30, a member of the tumor necrosis factor receptor superfamily, has been found to be preferentially expressed by human T cell clones exhibiting a Th2-line profile and function. We investigated whether there are derangement in CD30 expression in tissues, and/or abnormalities in soluble CD30 (sCD30) levels in the serum, or both, of three children with OS and one child with maternal engraftment and Omenn's-like syndrome (OLS). Large proportions of tissue-infiltrating T lymphocytes from all four patients expressed CD30, whereas in control tissues, including peripheral blood, CD30+ T lymphocytes were extremely few or absent. In addition, levels of sCD30 were abnormally increased in all patients' sera. T cell clones were generated from sorted CD30+ and CD30-peripheral blood T cells of the patient with OLS who showed unusually high numbers of circulating CD30+ T lymphocytes. Most CD4+ T cell clones derived from CD30+ cells showed a Th2-like cytokine profile, whereas the majority of clones generated from CD30-T cells were Th1. These findings support the hypothesis that Th2 cells are involved in the pathogenesis of OS. Moreover, they provide evidence that detection of CD30+ T cells in tissues, increased levels of sCD30 in biological fluids, or both, reflect the presence of immune responses characterized by prevalent activation of T cells producing Th2 cytokines.

Cytokines↗
PubMed1996

Ontogeny of CD40L [corrected] expression by activated peripheral blood lymphocytes in humans.

The CD40 ligand (CD40L) is a molecule expressed by activated T cells which plays a critical role in the regulation of B-cell responses, including differentiation into Ig-producing cells. Using the specific monoclonal antibody TRAP1 we have evaluated the ontogeny of CD40L expression in 97 normal individuals between birth and 50 years of age. The expression of CD40L is a function of age; it is severely reduced at birth, progressively increases during the first months of life, and reaches a plateau in the second decade. This progressive attainment of the ability to express CD40L is due to a process of maturation of the CD4 + subset, being significantly correlated with the expression of the CD45RO antigen.

Adolescent↗
PubMed1996

Defective expression of HLA class I and CD1a molecules in boy with Marfan-like phenotype and deep skin ulcers.

We report the case of a boy with low expression of HLA class I molecules on peripheral blood mononuclear cells, which is associated with immunodeficiency. The patient, who had a Marfan-like phenotype, had chronic deep skin ulcers and sinobronchiectasis. Immunohistologic examination of the ulcerated skin showed a dense perivascular infiltrate composed of normal mature lymphocytes and macrophages. All cells in the infiltrate showed an apparently normal expression of HLA class I molecules, but intraepidermal dendritic Langerhans' cells were negative for CD1a, an antigen that is a highly specific marker for these cells and is abundantly expressed in some self-healing forms of cutaneous lesions. It is therefore speculated that a defective expression of CD1a molecules can contribute to the chronic persistence of deep skin ulcers, which have already been reported in association with defective expression of HLA class I molecules.

Adolescent↗
PubMed1996

Immunodeficiencies caused by genetic defects in protein kinases.

The recognition that defects of ZAP-70 and, more recently, of JAK3 kinase in humans result in severe combined immunodeficiency, and the demonstration that targeting of these and other protein-kinase genes in mice also leads to immunodeficiency, have highlighted the crucial role that these proteins play in T-cell differentiation and activation.

Animals↗
PubMed1996

Signaling via IL-2 and IL-4 in JAK3-deficient severe combined immunodeficiency lymphocytes: JAK3-dependent and independent pathways.

Both IL-2 and IL-4 bind to receptors containing the common gamma chain and JAK3. Although JAK3 is required for proper lymphoid development, the precise roles of this kinase in IL-2 and IL-4 signaling in lymphocytes have not been defined. Here, we have studied IL-2 and IL-4 signaling in B cell lines lacking JAK3. Although IL-2-induced phosphorylation of IL-2R beta, JAK1, and STAT5 all required the presence of JAK3, IL-4-mediated phosphorylation of JAK1, STAT6, and insulin receptor substrates 1 and 2 did not. However, IL-4-induced effects were clearly improved following JAK3 expression. These data indicate that IL-4 signaling occurs in the absence of of JAK3, but is comparatively inefficient. These findings may help in understanding the pathogenesis of the immunodeficiency that occurs with mutations of JAK3 and may suggest a mechanism for the pleiotropic effects of IL-4.

B-Lymphocytes↗
PubMed1996

CD4+ cells from patients with Common Variable Immunodeficiency have a reduced ability of CD40 ligand membrane expression after in vitro stimulation.

BACKGROUND: Common Variable Immunodeficiency (CVID) is characterized by defective antibody production. This has been variably attributed to intrinsic B-cell defects or to T-cell disfunctions. Recently, it has been reported that the expression of the CD40 Ligand (CD40L), a T-cell surface molecule that plays a critical role in the cell-contact-mediated helper signals provided to B-cells, is defective in a subset of patients with CVID. METHODS: To demonstrate that the defective expression is due to intrinsic functional abnormalities of CD4+ lymphocytes, CD4+ cells were purified from eight patients with CVID and eight age-paired controls, stimulated with PMA+Ionomycin, and studied for CD40L expression by flow cytometry using specific monoclonal antibodies. RESULTS AND CONCLUSIONS: The percentage of CD4+ cells expressing CD40L after optimal stimulation was correlated with age both in patients with CVID (r: 0.74; p: 0.04) and in healthy controls (r: 0.73; p: 0.04). The percentage of CD40L+ cells was reduced in patients with CVID compared to that of controls (p: 0.02 when data are paired for age) with a reduced density of expression (p: < 0.01). The defect was variable in different patients and in some cases it was marginal.

Adolescent↗
PubMed1996

Intravenous immune globulin in the treatment of intractable childhood epilepsy.

Many clinical and experimental data strongly support the role of immune mechanisms in the pathogenesis of childhood epilepsy. Following Pechadre's first observations with intramuscular immune globulin (IMIG), intravenous immune globulin (IVIG) has been employed in some forms of intractable childhood epilepsy (ICE), mainly in West syndrome (WS) and Lennox Gastaut syndrome (LGS), with good results. So far, 373 children suffering from ICE have been treated in 29 studies and 174 have responded favourably. Although these studies are heterogeneous and controls are lacking, most authors report similar responsiveness ranging from 30% to 50%. Several mechanisms have been suggested to account for the efficacy of IVIG in ICE including antiviral effect, substitutive therapy in patients with concomitant humoral immunodeficiency, idiotype-anti-idiotype interaction or a neuromodulant effect. To better define the real efficacy of IVIG in ICE in paediatric patients, a randomized, multicenter, double-blind clinical trial was started in 1993, including only patients suffering from WS and LGS. To date, only one double-blind trial had been carried out (with both adult and paediatric patients); it showed a clear trend in favour of IVIG treatment but lacked statistical significance, perhaps because of the small and heterogeneous sample. Controlled multicentre studies on well-defined populations are needed and patients with WS and LGS are probably the best candidates.

Adolescent↗
PubMed1995

High prevalence of nonsense, frame shift, and splice-site mutations in 16 patients with full-blown Wiskott-Aldrich syndrome.

Wiskott-Aldrich syndrome (WAS) is a fully penetrant X-linked recessive disorder characterized by immunodeficiency, thrombocytopenia, and severe eczema. WAS is a life-threatening disease, with a poor quality of life and high mortality rate in childhood. The gene responsible for the disease has been localized to the proximal short arm of the X-chromosome and recently isolated through positional cloning and named WAS protein (WASP). We have characterized 17 WAS families. We have developed a rapid, nonradioactive screening protocol for identifying WASP gene alterations in genomic DNA. Our method allows simultaneous evaluation of single strand confirmation polymorphism and heteroduplex formation. We have identified 15 novel mutations that involve single basepair changes, or small insertions or deletions, all of which result in premature stop cordon, frame shift with secondary premature stop codon, or splice site defect. These studies document the considerable heterogeneity of the location of mutations in the WASP gene causing full-blown WAS and show the efficiency and rapidity of a screening approach for mutation identification in WAS that will be useful for carrier detection and prenatal diagnosis.

Base Sequence↗
PubMed1995

Gene therapy in peripheral blood lymphocytes and bone marrow for ADA- immunodeficient patients.

Adenosine deaminase (ADA) deficiency results in severe combined immunodeficiency, the first genetic disorder treated by gene therapy. Two different retroviral vectors were used to transfer ex vivo the human ADA minigene into bone marrow cells and peripheral blood lymphocytes from two patients undergoing exogenous enzyme replacement therapy. After 2 years of treatment, long-term survival of T and B lymphocytes, marrow cells, and granulocytes expressing the transferred ADA gene was demonstrated and resulted in normalization of the immune repertoire and restoration of cellular and humoral immunity. After discontinuation of treatment, T lymphocytes, derived from transduced peripheral blood lymphocytes, were progressively replaced by marrow-derived T cells in both patients. These results indicate successful gene transfer into long-lasting progenitor cells, producing a functional multilineage progeny.

Adenosine Deaminase↗