Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 5-year-old boy with spastic quadriplegia, T cell immunodeficiency, hypouricemia and immune cytopenias from age 8 months, was found to have purine nucleoside phosphorylase (PNP) deficiency, and developed chronic lung disease. Successful matched sibling BMT for PNP deficiency has not previously been reported. BMT using marrow from an HLA-identical sibling donor was performed after conditioning with busulfan (16 mg/kg), cyclophosphamide (200 mg/kg), melphalan (90 mg/m2) and anti-thymocyte globulin (36 mg/kg). T lymphocyte numbers, PNP activity and uric acid levels rapidly improved and he remains well 12 months after transplant.
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PMID:Late diagnosis and correction of purine nucleoside phosphorylase deficiency with allogeneic bone marrow transplantation. 867 45

Purine nucleoside phosphorylase deficiency is an inherited disease of purine metabolism characterized clinically as combined immunodeficiency. The molecular defects have been published for 4 different alleles in 3 patients. We report four new mutations including two amino acid substitutions, A174P and G190V, a single codon deletion, delta I129, and a point mutation in intron 3 which leads to aberrant splicing and creation of a premature stop codon in exon 4 (286-18G-->A). Of the previously reported mutations, E89K was found in one additional patient, and R234P was found in 3 unrelated patients, making R234P the most common mutation reported to date in this disease.
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PMID:Mutations in purine nucleoside phosphorylase deficiency. 906 51

Purine nucleoside phosphorylase (PNP) deficiency is a rare immunodeficiency disease involving a T-lymphocyte-dysfunction that is fatal unless bone marrow transplantation is successful. In this study we undertook genetic analysis of a patient with PNP deficiency. Sequencing of the PNP gene, which is located on chromosome 14ql3, of the patient led to the identification of three point mutations in exon 2 at amino acid positions 20 (His, silent mutation), 24 (Arg-->termination codon) and 51 (Ser-->Gly). Intrafamilial sequence analysis of exon 2 revealed that both parents were heterozygous for the Arg24 and termination codon 24 alleles. Two of their three children had inherited different homozygous alleles, termination codon 24 for the patient, and Arg24 for his healthy sibling. Transcriptional termination was suggested as the mechanism giving rise to the disorder in this case. A lack of PNP protein was also confirmed by immunoblot analysis of the patient's hemolysate. This could be the first report providing evidence of autosomal recessive inheritance in PNP deficiency by sequence-based analysis.
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PMID:Direct evidence of autosomal recessive inheritance of Arg24 to termination codon in purine nucleoside phosphorylase gene in a family with a severe combined immunodeficiency patient. 973 81

We generated purine nucleoside phosphorylase (PNP)-deficient mice to gain insight into the mechanism of immune deficiency disease associated with PNP deficiency in humans. Similar to the human disease, PNP deficiency in mice causes an immunodeficiency that affects T lymphocytes more severely than B lymphocytes. PNP knockout mice exhibit impaired thymocyte differentiation, reduced mitogenic and allogeneic responses, and decreased numbers of maturing thymocytes and peripheral T cells. T lymphocytes of PNP-deficient mice exhibit increased apoptosis in vivo and higher sensitivity to gamma irradiation in vitro. We propose that the immune deficiency in PNP deficiency is a result of inhibition of mitochondrial DNA repair due to the accumulation of dGTP in the mitochondria. The end result is increased sensitivity of T cells to spontaneous mitochondrial DNA damage, leading to T cell depletion by apoptosis.
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PMID:Mitochondrial basis for immune deficiency. Evidence from purine nucleoside phosphorylase-deficient mice. 1085 43

Purine nucleoside phosphorylase deficiency is a primary immunodeficiency syndrome characterized by the triad of recurrent infection, neurologic dysfunction, and autoimmunity. This patient presented atypically with few infections and normal T-cell function. Progressive lymphopenia, ataxia, and developmental delay led to diagnosis. Umbilical cord blood transplantation corrected the immunodeficiency.
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PMID:Purine nucleoside phosphorylase deficiency (PNP-def) presenting with lymphopenia and developmental delay: successful correction with umbilical cord blood transplantation. 1552 Jul 87

Purine nucleoside phosphorylase (PNP) is an intracellular enzyme crucial for purine degradation. PNP defects result in metabolic abnormalities and fatal T cell immunodeficiency. Protein transduction domains (PTD) transfer molecules across biological membranes. We hypothesized that fusion of PTD to PNP (PTD-PNP) would be an effective method for treating PNP deficiency. We find that PTD-PNP rapidly enters PNP-deficient lymphocytes and increases intracellular enzyme activity for 96 h. Similar to endogenous PNP, PTD-PNP is predominantly distributed in the cytoplasm. PTD-PNP improve viability and correct abnormal functions of PNP-deficient T lymphocytes including their response to stimulation and IL-2 secretion. Intracellular transduction protects PTD-PNP from antibody neutralization and from elimination, which may also provide significant in vivo therapeutic advantages to PNP. In conclusion, PTD fusion is an attractive method for extended PNP intracellular enzyme replacement therapy for PNP-deficient patients as well as for the intracellular delivery of other proteins.
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PMID:Intracellular delivery of purine nucleoside phosphorylase (PNP) fused to protein transduction domain corrects PNP deficiency in vitro. 1693 May 74

Progressive multifocal leukoencephalopathy is a demyelinating disease caused by JC virus, an opportunistic infection of the central nervous system. Although the majority of cases are infected with the human immunodeficiency virus (HIV), other immunocompromised patients are also at risk. Purine nucleoside phosphorylase is an enzyme in the purine salvage pathway that reversibly converts inosine to hypoxanthine and guanosine to guanine. Purine nucleoside phosphorylase deficiency is a combined immunodeficiency with a profound cellular defect. Neurologic abnormalities are salient features of this syndrome. We describe for the first time a patient with this rare disorder presented with progressive multifocal leukoencephalopathy.
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PMID:Progressive multifocal leukoencephalopathy in purine nucleoside phosphorylase deficiency. 1694 40

Defects in purine nucleoside phosphorylase (PNP) enzyme activity result in abnormal nucleoside homeostasis, severe T cell immunodeficiency, neurological dysfunction, and early death. Protein transduction domain (PTD) can transfer molecules into cells and may help restore PNP activity in cases of PNP deficiency. However, long-term use of PTD to replace enzymes in animal models or patients has not previously been described. We fused human PNP to the HIV-TAT PTD and found that the fusion with TAT changed the retention and distribution of PNP in PNP-deficient mice. TAT induced rapid intracellular delivery of PNP into tissues, including the brain, prevented urinary excretion of PNP, and protected PNP from neutralizing antibodies, resulting in significant extension of the enzyme's biological activity in vivo. Frequent TAT-PNP injections in PNP-deficient mice corrected the metabolic disorder and immune defects with no apparent toxicity. TAT-PNP remained effective over 24 weeks of treatment, resulting in continued improvement in immune function and extended survival. Our data demonstrate that TAT changes the properties of PNP in vivo and that long-term intracellular delivery of PNP by TAT corrects PNP deficiency in mice. We provide evidence to promote further use of PTD to treat diseases that require repeated intracellular enzyme or protein delivery.
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PMID:TAT-mediated intracellular delivery of purine nucleoside phosphorylase corrects its deficiency in mice. 1696 10

Purine nucleoside phosphorylase deficiency is a rare autosomal recessive immunodeficiency disease. The characteristic features of the disease include severe T cell immune defects with recurrent infections, a failure to thrive, and progressive neurological findings. To date, 35 cases of purine nucleosidase phosphorylase deficiency have been reported worldwide. A 2-year-old female patient was hospitalized due to recurrent infections starting from 6 months and a fever that had continued for a month. The parents were first cousins. Physical examination showed a failure to thrive, herpetic lesions around the lips, painful lesions on the tongue and the buccal mucosa, lung infection, and spastic paraparesis in the lower extremities. She had motor and mental retardation. Laboratory tests revealed lymphopenia; low CD3, CD4, and CD8 counts; normal immunoglobulin levels; low uric acid; and very low purine nucleoside phosphorylase enzyme activity (1.4 nmol/h/mg; normal range, 490-1530). DNA sequencing of the purine nucleosidase phosphorylase gene revealed a missense homozygous mutation, a G to A transition at exon 4 position 64 (349G>A transition), which led to a substitution of alanine by threonine at codon 117 (Ala117Thr). Both parents were heterozygous for the mutation. This is the second purine nucleosidase phosphorylase deficient case to have been presented and carrying this mutation worldwide. Various antibiotics, antifungal drugs, and intravenous immunoglobulin were used to treat the infections during her 3 months. This form of treatment proved to be unresponsive, resulting in her subsequent death at 26 months of age.
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PMID:Purine nucleoside phosphorylase deficiency in a patient with spastic paraplegia and recurrent infections. 1764 Dec 61

Purine nucleoside phosphorylase (PNP) catalyzes the reversible phosphorolysis of ribonucleosides and 2'-deoxyribonucleosides to their respective bases. Endogenous PNP deficiency leads to specific T-cell immunodeficiency, a genetic disease that has prompted the development of PNP inhibitors as potential therapies for T-cell-mediated diseases. PNP inhibition leads to the elevation of 2'-deoxyguanosine levels and accumulation of intracellular deoxyguanosine 5'-triphosphate, inducing cellular apoptosis. Forodesine is a highly potent, orally active, rationally designed PNP inhibitor that has shown activity in preclinical studies with malignant cells and clinical utility against T-cell acute lymphoblastic leukemia and cutaneous T-cell lymphoma. Additional preliminary findings support its use for the management of some B-cell malignancies.
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PMID:Purine nucleoside phosphorylase inhibition as a novel therapeutic approach for B-cell lymphoid malignancies. 1808 44


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