Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “inborn errors of immunity”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 289 records · Page 16Linked to original sources
PubMed1973

Human phosphoribosylpyrophosphate synthetase: increased enzyme specific activity in a family with gout and excessive purine synthesis.

Among affected members of a family (B. family) with excessive purine production and gout, activity of phosphoribosylpyrophosphate synthetase (EC 2.7.6.1) is 2.5- to 3.0-fold higher than among normal people. The molecular basis for this increased enzyme activity was studied. Antibody to purified human phosphoribosylpyrophosphate synthetase of erythrocytes was obtained from immunized rabbits. Studies with the IgG fraction of this antiserum show the presence of normal quantities of immunoreactive enzyme, but 2.5- to 3.0-fold higher activity per molecule in affected members of the B. family. In addition, by use of a stain for phosphoribosylpyrophosphate synthetase activity, a difference in electrophoretic mobility was demonstrated on cellulose acetate gel between the partially purified enzyme from normal people and an affected member of the B. family. These studies suggest that the enzyme aberration responsible for purine overproduction and gout in the B. family results from a structurally altered enzyme with increased activity per molecule.

Animals↗
PubMed1977

Clinical conditions associated with defective polymorphonuclear leukocyte chemotaxis.

Impressive numbers of clinical conditions are associated with defective leukocyte chemotaxis. In many, this cellular dysfunction is associated with other abnormalities of the immune response, but in others abnormal chemotactic responsiveness of leukocytes is the only abnormality of function identified in the laboratory. Patients are usually selected for study because of unusually severe, recurrent infections or poor response to antimicrobial agents, and therefore a frequent association between abnormality of chemotaxis and infection would be expected. Many patients demonstrate abnormal chemotaxis during remissions as well as during infections, and there seems little doubt that abnormality of chemotaxis is related to susceptibility to infections. Partial classification of disorders of chemotaxis was attempted. Major abnormalities are found when there is a primary cellular disorder or cell-directed inhibitors of chemotaxis are found. Less marked abnormalities are found when chemotactic factors are deficient.

Bacterial Infections↗
PubMed1994

Food allergy and food intolerance--what is the difference?

The literature is contradictory concerning the use (and misuse) of the terms "food allergy" and "food intolerance." When using double-blind, placebo-controlled food challenge as the gold standard, the clinical picture characterizing both diseases is identical, ie, concomitant signs and symptoms from the skin, gastrointestinal-tract and respiratory system (classical allergic signs and symptoms). A distinction between food allergy and food intolerance thus depends on whether the involvement of the immune system can be verified. The basic problem with diagnostic tests such as skin prick test (SPT), measurement of specific IgE (RAST) or histamine release from basophils (HR) is that in contrast to inhalant allergens, no standardized extracts are commercially available. It is therefore often not possible to discriminate between the ability of a test per se in the diagnosis of food allergy and differences in allergen extract quality. This is probably the reason for the great variability in diagnostic sensitivity and specificity reported in the literature. Many cases of food allergy to proteins may be therefore misdiagnosed as food intolerance due to a low sensitivity of the tests (SPT, RAST, and HR) used.

Double-Blind Method↗
PubMed1994

Ethylmalonic aciduria: an organic acidemia with CNS involvement and vasculopathy.

Five infants from 3 families, one Egyptian, two Yemeni, are described with a progressive encephalopathy, four of whom have been studied in detail. All patients showed vascular lesions of the skin, characterized by waxing and waning petechiae and ecchymoses. Acrocyanosis was present in three patients. All patients showed retinal lesions characterized by tortuous veins. Protracted diarrhea was not a consistent finding, although they had metabolic crisis in association with diarrhea. They did not show failure to thrive. The neurologic symptoms were indicative of a progressive pyramidal tract disease. Three patients died following sudden emergence of severe basal ganglia, putaminal and head of caudate lesions. In one patient the CT changes in brain were suggestive of infarction. The patients who died manifested pulmonary congestion, or wet lung, and respiratory difficulties during the terminal stage of the disease. In all patients before and during the terminal event, mild-to-moderate hematuria, and in two RBC in CSF, was observed. In one patient there was mild hemoperitoneum at the terminal event. The urine organic acids indicated increased excretion of ethylmalonic, methylsuccinic, glutaric, and adipic acids. The patients invariably showed lactic acidosis, but no ketosis, during and in between the acidotic attacks of the disease. The acylcarnitine profile in blood of two patients showed a pronounced increase in C4 and C5 carnitine esters. In three patients, biopsies from petechiae indicated absence of an immune event, showing only fresh hemorrhage. An immunologic study in one patient was normal for the suppressor:cytotoxic lymphocyte ratio and concentration of interleukin-2 receptor during and in between hemorrhagic attacks. The cytochrome c oxidase activity in fibroblasts was normal. The rate of oxidation of glucose, leucine, isoleucine, valine, propionate and butyrate by fibroblasts was normal. The disease is not responsive to treatment with riboflavin, ascorbic acid, vitamin E, glycine, or carnitine. One patient remained stable on prolonged large doses of methylprednisolone. The biochemical defect leading to ethylmalonic aciduria in this disease remains unknown.

Acidosis↗
PubMed2002

Severe neurologic complications after hematopoietic stem cell transplantation in children.

OBJECTIVE: To describe and evaluate the incidence and risk factors of severe neurologic events (SNE) in pediatric recipients of allogeneic or autologous hematopoietic stem cell transplantation (HSCT) for hematologic or nonhematologic diseases. METHODS: Retrospective analysis of 272 consecutive children admitted to the G. Gaslini Children's Research Institute and given HSCT (70 from unrelated donors, 115 from related donors, and 87 autologous) between June 1985 and January 2001. RESULTS: Thirty-seven children (13.6%) developed SNE after a median of 90 days (range, 5 days to 8.8 years) after HSCT. Cyclosporine A (CSA) neurotoxicity was the most frequent SNE (n = 21), followed by irradiation or chemotherapy injury (n = 7), CNS infections (n = 7), cerebrovascular events (n = 3), and immune-mediated etiology SNE (n = 2). Eleven patients (30%) died because of the neurologic complications. Type of HSCT, treatment with total body irradiation (TBI), acute graft-vs-host disease (GvHD), GvHD >grade 2, and treatment with CSA were associated with a significant increased risk of SNE. CONCLUSIONS: Severe neurologic complications are frequent (14%) among children receiving HSCT, causing 8.5% of deaths after transplant. Transplant from allogeneic donor, especially if unrelated, the development of severe acute GvHD grade >2, and the use of TBI in the preparative regimen are the main risk factors for such complications.

Adolescent↗
PubMed1996

Bone marrow transplantation from genetically HLA-nonidentical donors in children with fatal inherited disorders excluding severe combined immunodeficiencies: use of two monoclonal antibodies to prevent graft rejection.

OBJECTIVE: For children with life-threatening inborn errors of metabolism without a matched related bone marrow donor, transplantation from an HLA genetically nonidentical donor is the only therapeutic option. To reduce the high risk of graft rejection in this setting without increasing the conditioning regimen, a protocol based on the infusion of an antiadhesion antibody directed against the CD11a (leukocyte function-associated antigen 1 [LFA-1]) molecule was performed by the European Bone Marrow Transplantation-European Society for Immunodeficiency group with promising results. To optimize engraftment, and thereby survival, further, the additional blockade of a second important leukocyte adhesion and signalization pathway mediated by the CD2 and LFA-3 interaction was attempted in a multicenter protocol conducted by the European Bone Marrow Transplantation-European Society for Immunodeficiency group. Results of this study (ie, engraftment and survival) were compared with a historical control group that received the anti-LFA-1 antibody alone. Factors that may have affected engraftment and survival were also considered in this study. METHODS: Forty-four children with inborn errors, including inherited immunodeficiencies (excluding severe combined immunodeficiencies), Chédiak-Higashi syndrome, familial hemophagocytic lymphohistiocytosis, and malignant osteopetrosis, received bone marrow from HLA-nonidentical related donors or from HLA-identical unrelated donors at 13 European centers between August 1990 and June 1993. Bone marrow was depleted of T cells by use of either erythrocyte (E) rosetting or monoclonal antibodies (MoAbs) to prevent graft-versus-host disease. The conditioning regimen consisted of busulfan and cyclophosphamide for all patients plus etoposide for patients with osteopetrosis, familial hemophagocytic lymphohistiocytosis, and Chédiak-Higashi syndrome. Infusions of MoAbs specific for the CD11a and the CD2 molecules were started 4 and 3 days, respectively, before and continued through the first 10 and 11 days, respectively, after bone marrow transplantation (a total of 14 injections). RESULTS: The overall sustained engraftment rate was 69.8%, with full chimerism in 80.6% of patients and no late graft rejection with the use of two MoAbs versus 65.7% and 58.1%, respectively, in the control group, in which only one MoAb was infused. The overall actuarial survival rate with a functional graft was 40.9%, with a mean follow-up of 39.3 months with two MoAbs versus 37.8% with one. The engraftment rate was significantly influenced by the T-cell depletion method, with better results for recipients of E rosette- depleted marrow (78.6% vs 20% for Campath 1-M plus complement-depleted marrows). Graft-versus-host disease and the kinetics of immune reconstitution were similar in both groups. CONCLUSIONS: The overall engraftment rate and overall survival rate with engraftment in patients treated with anti-LFA-1 and anti-CD2 were similar to those in patients treated with anti-LFA-1 antibody alone. However, although the number of patients is too small to draw definitive conclusions, results from the combined use of the two MoAbs indicates a trend toward better engraftment and survival after infusion of E rosette-depleted marrow. Further improvement in survival would demand additional strategies to hasten immunologic recovery.

Antibodies, Monoclonal↗
PubMed1990

Carbohydrate deficient serum transferrin in a new systemic hereditary syndrome.

Four patients with a new, inherited, complex developmental deficiency syndrome were studied. The syndrome affects the central and peripheral nervous system, and also the retina, liver, bone, adipose tissue, and genital organs. Abnormalities of glycoproteins, glycopeptide hormones, and lipids have been found in serum from these patients, the most pronounced being increased cathodal forms of transferrin. Isoforms of serum transferrin were therefore analysed qualitatively and quantitatively by isoelectric focusing and isocratic anion exchange chromatography, and the carbohydrate composition was determined in transferrin isolated by immune affinity chromatography. All the patients had about tenfold raised serum concentrations of isotransferrins with higher isoelectric points than normal. Similar findings, though less pronounced, were made in all the fathers and in one of the mothers. Half the transferrin in the patients was constantly present in two principal abnormal cathodal forms in approximately equal amounts. Carbohydrate determinations in purified transferrin showed quantitatively similar deficiencies of sialic acid, galactose, and N-acetylglucosamine, the mannose content being normal. The results suggest that either two or all of the normally four terminal trisaccharides in transferrin may be missing. A defect in the synthesis or catabolism, or both, of this trisaccharide, which is common to many secretory glyco-conjugates, is likely. Apart from providing a quantitative diagnostic method, the present findings may serve as a basis for further studies of the metabolic deficiency in this syndrome.

Biomarkers↗
PubMedDate not supplied

Preclinical development strategies for novel gene therapeutic products.

With over 220 investigational new drug applications currently active, gene therapy represents one of the fastest growing areas in biotherapeutic research. Initially conceived for replacing defective genes in diseases such as cystic fibrosis or inborn errors of metabolism with genes encoding the normal, or wild-type, gene product, gene therapy has expanded into other novel applications such as treatment of cancer or cardiovascular disease, where the risk:benefit profiles may be more acceptable in relation to the severity of the disease. Different types of vectors, including modified retroviruses, adenoviruses, adenovirus-associated viruses, and herpesviruses and plasmid DNA, are used to transfer foreign genetic material into patients' cells or tissues. Developing a toxicology program to determine the safety of these agents, therefore, requires a modified approach that encompasses the pharmacology and toxicity of both the gene product itself and the vector system used for delivery in the context of the application for the clinical trial. In general, the issues involved in designing and developing appropriate preclinical testing to determine the safety of these products are similar to those encountered for other recombinant molecules, including protein biotherapeutics. Limitations to some of the typical toxicology studies conducted for a traditional drug development program may exist for these agents, and nontraditional approaches may be required to demonstrate their safety. Many factors may affect the safety and clinical activity of these agents, including the route, frequency, and duration of exposure and the type of vector employed. Other safety considerations include quantitation of the duration and degree of expression of the vector in target and other tissues, the effects of gene expression on organ pathology and/or histology, evaluation of trafficking of gene-transduced cells or vector after injection, and interactions of the host immune system with the transduced cell population. Because of the unique concerns regarding each of these therapies, the Center for Biologics Evaluation and Research encourages sponsors to obtain toxicity data whenever possible while evaluating the pharmacologic activity of the vector in a species or animal model relevant to their clinical indication. Sponsors are encouraged to discuss preclinical study design and results with the Center during product development to facilitate early identification of safety concerns prior to entry of these novel agents into the clinical setting and to ensure an uninterrupted course of development while addressing issues required for licensure.

Animals↗
PubMed1983

Inherited purine enzyme deficiencies: prenatal diagnosis and heterozygote detection.

A number of genetically determined enzyme defects leading to disturbances of purine metabolism can prenatally be monitored, and heterozygote detection is possible in several cases. In severe hypoxanthine-guanine phosphoribosyl transferase (HGPRT) deficiency, associated with a neurological disease known as the Lesch-Nyhan Syndrome, rapid prenatal diagnosis can be performed by means of a simple quantitative radiochemical enzyme assay at the single cell level. In this X-linked recessive disease, the female heterozygotes can be detected by using cultured skin fibroblasts, but alternatively single hair root enzymes can directly be assayed. Two other genetic purine enzyme defects lead to deranged immune function: in adenosine deaminase (ADA) deficiency both T- and B-lymphocyte function are severely impaired. In purine nucleoside phosphorylase (PNP) deficiency, only certain T-cell abnormalities have been observed, with apparently normal B-cell function. Both diseases are transmitted as autosomal recessive traits. Prenatal diagnosis is possible, e.g. by means of the above mentioned microtechniques. Heterozygote detection can be done using blood cells or cultured fibroblasts. Microchemical methods offer the possibility to perform enzyme characterisation even when a very limited amount of material is available. In the case of HGPRT, ADA, and PNP, for a substrate affinity curve and pH optimum curve a few hundred cells are sufficient. These and other possibilities illustrate the general usefulness of simple microtechniques in clinical enzymology.

Adenosine Deaminase↗
PubMed1990

Bone marrow transplantation for genetic disorders.

In 1967, a congenital disorder, severe combined immune deficiency disease, (SCID), was the first condition to be successfully corrected by bone marrow transplantation (BMT) from a histocompatible matched sibling donor. Since then the number of inherited disorders in which BMT has been used has been greatly extended. In preface, it should be stressed that BMT represents only one aspect of the management of genetic disorders which includes first and foremost detection and prevention by antenatal screening. Enzyme replacement treatment and the development of genetic engineering techniques to correct the underlying fault are being actively explored. However, reliable screening programmes are only feasible in a minority of disorders, of which thalassaemia is an example. Enzyme replacement treatment has been largely unsuccessful, and despite considerable advances in the understanding of gene regulation, at present BMT represents the only practice capable of correcting genetic disorders and improving the quality of life of affected individuals.

Bone Marrow Transplantation↗
PubMedDate not supplied

[Glutaric aciduria type 1: an example of the importance of early detection of so-called cerebral organic aciduria].

Glutaric aciduria type 1 (GA 1) is a preventable cause of acute brain damage in early childhood, leading to a severe dystonic-dyskinetic disorder. Typically between 6 and 18 months of age, a non-specific illness such as respiratory or gastrointestinal infection or immunization leads to encephalopathic crisis, usually resulting in degeneration of the putamen and caudate. GA 1 is an autosomal recessive disease of catabolism of amino acids lysine, hydroxylysine and tryptophane leading to accumulation of glutaric acid, 3-hydroxyglutaric acid and glutaconic acid. Recognition of this biochemical disorder before the brain has been injured is essential to the outcome. Diagnosis depends upon the recognition of relatively non-specific physical findings such as hypotonia, tremor, irritability and macrocephaly, and on urinary organic acids analysis. The diagnosis may also be suggested by characteristic findings of neuroimaging. Specific management includes pharmacological doses of 1-carnitine and dietary protein restriction. Metabolic decompensation must be treated vigorously to avoid permanent brain damage. With this case report the authors want to contribute to the early recognition of GA1, to the prevention of the related brain damage, and to increase awareness of the existence of so-called cerebral organic acidurias.

Amino Acid Metabolism, Inborn Errors↗
PubMed1999

Glutaric aciduria type I: from clinical, biochemical and molecular diversity to successful therapy.

The biochemical hallmark of glutaric aciduria type I (GA I) due to glutaryl-CoA dehydrogenase deficiency is the accumulation of glutaric acid, and to a lesser degree of 3-hydroxyglutaric and glutaconic acids. Abnormal metabolites vary from gross organic aciduria to only slightly or intermittently elevated or even normal excretion of glutaric acid, making the diagnosis sometimes difficult. Close to 100 pathogenic mutations have been identified in the gene encoding glutaryl-CoA dehydrogenase. Specific mutations correlate with low or no excretion of glutaric acid, but there appears to be no correlation between genotype and clinical phenotype. GA I causes unique age- and location-specific neuropathological sequelae. Starting in the second half of gestation, maturation of the frontal and temporal cortex is hindered, leading to the characteristic appearance of frontotemporal atrophy. Between 6 and 18 months of age, relatively mild neurological symptoms may become exacerbated by fever or a catabolic state in the course of common infections or routine immunizations, by fasts required for surgery, or by minor head injuries. Putamen and caudate are destroyed, resulting in a permanent movement disorder that is similar to cerebral palsy and ranges from extreme hypotonia to choreoathetosis to rigidity with spasticity. Recently, the underlying pathophysiology could be delineated to an environmentally triggered age- and location-specific overstimulation of the NMDA 2B receptor subtype. Current therapy prevents brain degeneration in more than 90% of affected infants who are treated prospectively. Without treatment, more than 90% of affected children will develop severe neurological disabilities. Recognition of this disorder before the brain has been injured is essential to treatment. GA I may be recognized in routine neonatal screening performed with tandem mass spectrometry by an elevation of glutarylcarnitine. Where this is not done, timely diagnosis depends on the recognition of relatively nonspecific physical findings such as hypotonia, irritability, macrocephaly, on the detection of suggestive abnormalities in neuroimaging and on quantitative urinary organic acid analysis by gas chromatography--mass spectrometry.

Animals↗
PubMed2004

The dynamic effects of breastfeeding on intestinal development and host defense.

In this review, evidence is provided to support the hypothesis that human milk provides a link between the mother and her newborn infant in the extrauterine environment in a manner similar to the placental link between mother and fetus in utero. In addition, breastfeeding helps prevent age-related diseases affecting the gastrointestinal tract during the newborn period. To provide evidence to support this hypothesis, anecdotal clinical studies are sited to suggest that human milk contains factors that may be missing in inherited diseases of inborn errors in metabolism and provide passive protective factors that lessen the expression of neonatal allergic and infectious diseases. In some instances, by providing the missing factor in an inherited disease, the newborn may be protected from serious damage to its developing brain. A second line of evidence to support this hypothesis is the observation that the composition of human milk varies with the infant's needs. To illustrate this principal, the composition of milk from mothers delivering prematurely and milk of mothers of full-term infants were compared, and the differences in trophic and protective factors in colostrum versus mature milk from mothers delivering full-term are cited. Finally, using observations from the laboratory that define the immaturities in neonatal and premature human intestinal defenses as the neonate's host defense deficiency, the specific effect that anti-inflammatory and maturational factors in human milk has on these immaturities is discussed. The active stimulus of maternal milk on the rapid development of host defenses is underscored. These cited examples of human milk effects in the newborn help support the stated hypothesis. Additional studies of human immature gut function along with translational and clinical studies are necessary to provide further objective evidence in support of breastfeeding for all neonates, particularly premature neonates.

Breast Feeding↗
PubMed1977

Purine nucleoside phosphorylase deficiency associated with selective cellular immunodeficiency.

We studied a 15-month-old girl who had normal T-cell and B-cell immunity at birth, after which a gradual decrease in T-cell immunity developed. This selective cellular immunodeficiency was inherited as an autosomal recessive trait: two older sisters had the same immunodeficiency. Adenosine deaminase activity was present in erythrocytes and lymphocytes of the patient, parents and a healthy brother. Purine nucleoside phosphorylase activity was not found in the patient's erythrocytes and lymphocytes (the parents and brother had intermediate values, indicating that the enzyme deficiency too was inherited as an autosomal recessive trait). Analysis of serum and urine from the patient and of serum from her two deceased sisters showed high levels of inosine and guanosine in addition to hypouricemia and hypouricosuria. The bone marrow was megaloblastic, and the blood hypochromic microcytic. The patient had spastic tetraparesis. Intoxication of the T lymphocytes after birth by metabolic products may explain the progressive cellular immunodeficiency.

B-Lymphocytes↗
PubMed1998

Varicella and varicella immunity in patients with lysinuric protein intolerance.

Two patients with lysinuric protein intolerance (LPI) had near-fatal generalized varicella infection with severe interstitial pneumonitis, hepatitis, decreased platelet count, bleeding and hypoalbuminaemia. Active haemolysis resulted in anaemia and massive haemoglobinuria. Serum lactate dehydrogenase activity and ferritin concentration, which in patients with LPI in normal circumstances exceed the upper reference values 3-folds to 10-fold, increased to > 10,000 U/L and > 10,000 micrograms/L, respectively. The patients were treated with fresh frozen plasma, red-cell transfusions and intravenous acyclovir for 14 days, and recovered clinically in a month. Retrospectively, 3 of the 32 other known Finnish patients with LPI had had varicella infection that had been more severe than that in the other children in the family or in subjects in the neighbourhood and had led to hospital admission. Varicella antibodies were measured in 24 patients; 5 had no antibodies and 5 had very low antibody titres. Primary vaccination of three patients with living varicella vaccine increased antibody titres measurably in one patient. We suggest that patients with LPI who have no varicella zoster antibodies should be treated with acyclovir if exposed to varicella and should be (re)vaccinated against chickenpox.

Adult↗
PubMed2007

Clinical and molecular genetic spectrum of congenital deficiency of the leptin receptor.

BACKGROUND: A single family has been described in which obesity results from a mutation in the leptin-receptor gene (LEPR), but the prevalence of such mutations in severe, early-onset obesity has not been systematically examined. METHODS: We sequenced LEPR in 300 subjects with hyperphagia and severe early-onset obesity, including 90 probands from consanguineous families, and investigated the extent to which mutations cosegregated with obesity and affected receptor function. We evaluated metabolic, endocrine, and immune function in probands and affected relatives. RESULTS: Of the 300 subjects, 8 (3%) had nonsense or missense LEPR mutations--7 were homozygotes, and 1 was a compound heterozygote. All missense mutations resulted in impaired receptor signaling. Affected subjects were characterized by hyperphagia, severe obesity, alterations in immune function, and delayed puberty due to hypogonadotropic hypogonadism. Serum leptin levels were within the range predicted by the elevated fat mass in these subjects. Their clinical features were less severe than those of subjects with congenital leptin deficiency. CONCLUSIONS: The prevalence of pathogenic LEPR mutations in a cohort of subjects with severe, early-onset obesity was 3%. Circulating levels of leptin were not disproportionately elevated, suggesting that serum leptin cannot be used as a marker for leptin-receptor deficiency. Congenital leptin-receptor deficiency should be considered in the differential diagnosis in any child with hyperphagia and severe obesity in the absence of developmental delay or dysmorphism.

Adult↗
PubMed1990

Different molecular basis for fumarylacetoacetate hydrolase deficiency in the two clinical forms of hereditary tyrosinemia (type I).

Hereditary tyrosinemia is characterized by a deficiency of the enzyme fumarylacetoacetate hydrolase (FAH; E.C.3.7.1.2), the last enzyme in the catabolic pathway of tyrosine. FAH was purified from rat and human liver and was used to immunize rabbits. Specific antibodies were used to probe protein extracts of livers and other tissues of normal and tyrosinemic patients. No immunoreactive FAH band was observed on immunoblots of liver, kidneys, and lymphocytes from patients presenting with the acute form of hereditary tyrosinemia. Patients with the chronic form had immunoreactive FAH at a level approximately 20% of normal liver values, which was correlated with the measured enzymatic activity. Immunoblot analysis of aborted fetal tissues revealed normal FAH immunoreactivity in normal liver and kidneys. No FAH immunoreactivity was found in liver and kidneys of tyrosinemic fetuses. The presence of FAH immunoreactivity in normal fetal tissues suggests that deficient FAH activity in tyrosinemia is not simply related to a developmentally regulated expression of the enzyme. By this immunoblot assay, FAH was detected in most human tissues, with maximal immunoreactivity in liver and kidneys and with only trace amounts in chorionic villi and cultured amniocytes. These data confirm that the primary defect in the acute form of hereditary tyrosinemia is an absence of FAH. Moreover, these data suggest that both clinical forms of the disease have a different molecular basis.

Amino Acid Metabolism, Inborn Errors↗
PubMed2001

An ethnic role for chronic, but not acute, graft-versus-host disease after HLA-identical sibling stem cell transplantation.

Among 424 HLA identical siblings undergoing stem cell transplantation, 364 were Scandinavians and 60 represented other ethnic groups. The cumulative probabilities of acute graft-versus-host disease grades II-IV were similar in both groups, 17% in Scandinavians and 12% in the others, p = 0.4. In a multivariate analysis, less effective immune suppression with cyclosporine or methotrexate alone (p = 0.001), recipient seropositive for three to four herpes viruses (p = 0.004), CMV-seropositive recipient (p = 0.05) and early engraftment (before day 15) (p = 0.05) were independent risk-factors for acute GVHD grades II-IV. The cumulative probabilities of chronic GVHD were 47% and 68% in the two ethnic populations, respectively (p = 0.004). In multivariate analysis, higher patient age (p < 0.001), non-Scandinavian population (p < 0.001) and immunised female donor to male recipient (p = 0.03) were independent risk factors for chronic GVHD. The higher incidence of chronic GVHD could not be explained by differences in HLA antigen frequencies. The cumulative probabilities of relapse were 37% in the both groups. This suggests that the Scandinavian population is more homogeneous with regard to minor histocompatibility antigens important for chronic, but not acute GVHD.

Acute Disease↗