Betty B. Wray

Loss of B Cells in Patients with Heterozygous Mutations in IKAROS.

BACKGROUND Common variable immunodeficiency (CVID) is characterized by late-onset hypogammaglobulinemia in the absence of predisposing factors. The genetic cause is unknown in the majority of cases, and less than 10% of patients have a family history of the disease. Most patients have normal numbers of B cells but lack plasma cells. METHODS We used whole-exome sequencing and array-based comparative genomic hybridization to evaluate a subset of patients with CVID and low B-cell numbers. Mutant proteins were analyzed for DNA binding with the use of an electrophoretic mobility-shift assay (EMSA) and confocal microscopy. Flow cytometry was used to analyze peripheral-blood lymphocytes and bone marrow aspirates. RESULTS Six different heterozygous mutations in IKZF1, the gene encoding the transcription factor IKAROS, were identified in 29 persons from six families. In two families, the mutation was a de novo event in the proband. All the mutations, four amino acid substitutions, an intragenic deletion, and a 4.7-Mb multigene deletion involved the DNA-binding domain of IKAROS. The proteins bearing missense mutations failed to bind target DNA sequences on EMSA and confocal microscopy; however, they did not inhibit the binding of wild-type IKAROS. Studies in family members showed progressive loss of B cells and serum immunoglobulins. Bone marrow aspirates in two patients had markedly decreased early B-cell precursors, but plasma cells were present. Acute lymphoblastic leukemia developed in 2 of the 29 patients. CONCLUSIONS Heterozygous mutations in the transcription factor IKAROS caused an autosomal dominant form of CVID that is associated with a striking decrease in B-cell numbers. (Funded by the National Institutes of Health and others.).

Seasonal variation in antigens of the imported fire ant Solenopsis invicta

Eight sequentially collected lots of aqueous extracts of imported fire ant (IFA) front end and abdominal end segments were assayed for phospholipase A (PLA), N-acetyl-beta-glucosaminidase (NAG), and hyaluronidase. Relative potency of each extract lot and pooled venom was measured by RAST inhibition against a venom standard. More than a hundredfold difference in PLA activity was observed. Early summer collections had the highest activity. The May to June collection had more than twice the PLA activity of the next most potent lot. Discordancy in enzyme patterns was noted only in AE extract. NAG levels peaked earlier in the spring and summer and fluctuated less widely. Front end extract had lower activity levels for both enzymes, with no seasonal fluctuation in NAG and a single elevation in PLA activity in the April to May collection. RAST inhibition varied directly with PLA activity (p less than .05) but not with NAG nor hyaluronidase activities. Fifty-one percent of systemic allergic reactions to IFA stings occurred in summer, and 19% occurred in spring. A reported demographic survey demonstrated a higher incidence of IFA stings in the spring (39.9%) with a lower attack rate in the summer (31.9%). These findings suggest that the rate of systemic reactions to stings of the IFA may be related to seasonal variations in allergenic potency, as measured by PLA and RAST inhibition, rather than the sting attack rate.

Analysis of aflatoxin B1 in human tissues with high-pressure liquid chromatography

Abstract Fast, reproducible, and sensitive methods for the extraction and analysis of aflatoxin B 1 in human liver, blood, and urine by high-pressure liquid chromatography are described. Recovery of aflatoxin B 1 from spiked mouse liver homogenates was quantitative (>97%) over a range of 1.6–1600 ng/g. Better than 79% recovery of aflatoxin B 1 was obtained from human blood samples spiked with 1–50 ng/ml. Using these procedures, liver samples from patients with primary hepatocellular carcinoma and liver, blood, and urine from patients diagnosed with Reyes syndrome were analyzed for aflatoxin B 1 . Aflatoxin B 1 was detected in 4 of the 6 liver samples from primary hepatocellular carcinoma patients. Aflatoxin B 1 also was detected in 11 of 14 liver samples, 4 of 6 blood samples, and 4 of 5 urine samples from patients with Reyes syndrome.

Hypersensitivity reactions to Escherichia coli –derived polyethylene glycolated–asparaginase associated with subsequent immediate skin test reactivity to E. coli–derived granulocyte colony-stimulating factor

L-asparaginase is a cancer chemotherapeutic agent derived from Escherichia coli. It is effective in treating acute lymphoblastic leukemia (ALL) and other related diseases, but it has been associated with hypersensitivity reactions in from 6% to 43% of patients studied.1 Such reactions can occur after one dose of the drug, but most occur after 2 weeks of daily or thrice weekly therapy.1 The highest prevalence has been observed when L-asparaginase was given as a single agent or when given in higher doses (6000 IU/m2).1 Mechanisms proposed for L-asparaginase reactions include trace endotoxin contamination, IgE-mediated hypersensitivity, IgG or IgM antibody–mediated sensitivity, and complement-mediated reactions.2 Use of intramuscular preparations of L-asparaginase has been associated with a decrease in severe hypersensitivity reactions without loss of efficacy.3 Polyethylene glycolated (PEG)–asparaginase is a further improvement to this because it has a sustained release from tissues and is longer acting. There have been reports of delayed hypersensitivity reactions to intramuscular L-asparaginase3; however, there have been no previously reported cases of anaphylaxis to PEG-asparaginase. Granulocyte colony-stimulating factor (G-CSF) (Filgrastim) and granulocyte-macrophage colony-stimulating factor (GM-CSF) (Sargramostim) are hematopoietic growth factors used in treating myelosuppression following cancer chemotherapy. They are structurally distinct, and are derived from different recombinant expression systems: G-CSF from E. coli and GM-CSF from Saccharomyces cerevisiae. Both have been associated with hypersensitivity reactions4, 5; however, they are not believed to be cross-reactive. Because both PEGasparaginase and G-CSF are produced in E. coli, there may be a theoretic concern regarding cross-sensitization in patients who have had life-threatening reactions to one of these agents. We present two cases of anaphylaxis to PEG-asparaginase and discuss our experience with skin testing these patients with G-CSF and GM-CSF.

Pediatric acquired immune deficiency syndrome with panhypogammaglobulinemia

Acquired immune deficiency syndrome has been characterized by T cell dysfunction, occasionally normal but more often elevated immunoglobul in levels, and ant ibody to the h u m a n immunodeficiency virus. 1 However, the manifesta t ions of HIV infection can be quite va r i ed ) We report a child with panhypogammaglobul inemia , which caused a delay in recognizing the diagnosis of H I V infection.

Specific anti-influenza virus antibody production in vitro by lymphocytes from a subset of patients with hypogammaglobulinemia.

Specific anti-influenza virus antibody production in vitro was studied in peripheral blood mononuclear cells from 17 patients with hypogammaglobulinemia. Cells obtained from 6 of 12 patients with common variable hypogammaglobulinemia produced anti-influenza virus antibody, predominantly of the IgM isotype, when cultured in vitro with type A influenza virus. No antibody was produced in vitro, however, by cells from either of two patients with Brutons type X-linked hypogammaglobulinemia or by cells from any of three patients with X-linked hypogammaglobulinemia and isolated growth hormone deficiency. These studies demonstrate that peripheral blood mononuclear cells from a subset of patients with common variable hypogammaglobulinemia retain the potential to produce specific antibody in response to antigenic stimulation.

Sjogren's syndrome in an adolescent

Sjogrens syndrome is a chronic autoimmune disorder characterized by keratoconjunctivitis sicca, xerostomia, and recurrent enlargement of the salivary glands. Most commonly noted in adults, it rarely affects adolescents. We describe a 15-year-old adolescent with recurrent parotid enlargement as an initial manifestation of this disease.

Immunoglobulin deficiency in children with a sudden overwhelming infection

BACKGROUND A small percentage of previously healthy children develop a sudden overwhelming infection (SOI) that rapidly progresses and results in shock and, occasionally, death. Some of these children may have an undetected Ig deficiency. OBJECTIVE The aim of this study was to evaluate the incidence of Ig deficiency in children with a SOI. METHODS A case series study was conducted in a university hospital and included 18 children who either died in the emergency room or required admission to the pediatric intensive care unit secondary to a SOI. Two age-matched control groups included children hospitalized to regular floor beds with an infectious process (infected control group) or a noninfectious process (noninfected control group). Serum left from the initial blood draw, before fluid resuscitation, was collected and stored at -70 degrees C. Total IgG, IgG subclasses, IgM, and IgA were assayed by rate nephelometry in a blinded fashion. RESULTS In the study group, one of six children under 1 year of age had low Ig levels in comparison with two of nine control patients. In those children over the age of 1 year, 8 of 12 patients (67%) had low Ig levels as compared with 2 of 19 controls (11%) by Fishers exact test, P = .002. Of those patients with Ig deficiencies, three of eight had isolated IgG deficiency, two of eight had combined IgG and IgA deficiency, three of eight had combined IgG and IgM deficiency. CONCLUSIONS Children over the age of 1 year who present with a SOI have a significantly higher incidence of Ig deficiencies compared with age-matched controls.

Congenital X-linked hypogammaglobulinemia and asymptomatic hepatitis B antigen carrier state

Hepatitis occurring in patients with congenital X-linked or common variable hypogammaglobulinemia has been reported to follow a usual pattern of rapid progression from acute hepatitis to either chronic active hepatitis or death. This article describes a 21-year-old black man with congenital X-linked hypogammaglobulinemia who has been known to be a hepatitis B-associated antigen carrier during a 9-year follow up period. Liver enzyme studies are normal. His immunologic studies demonstrate no impairment of cellular immunity. His brother, who has the same disease and lives in the same household, has remained negative for hepatitis B-associated antigen. This patient demonstrates that not all hypogammaglobulinemia patients invariably have a severe clinical course with hepatitis.

Precipitins to an aflatoxin-producing strain of aspergillus flavus in patients with malignancy

SummarySerum samples from 121 patients in whom malignant disease had been diagnosed, were assayed for precipitins to fungal isolates from leukemia-associated environments. Control sera were from age-, sex-, and race-matched patients with no history of malignant disease. Sera from 36 (30%) malignancy patients and seven (6%) controls yielded a precipitin band to an aflatoxin-producing Aspergillus flavus isolate from a leukemia-associated house χ2, p<0.05%). No significant numbers of precipitins were obtained to either of the other fungal isolates from that and another such house.Although A. fumigatus has frequently been incriminated as a source of infection in patients with malignancy, only 9% of malignancy patients had a precipitin response to it, as did 1.6% of controls. Also, the presence of the precipitins to A. flavus was not connected with past radiation or imunosuppressive therapy. However, among patients with precipitins to A. fumigatus there was a higher death rate in the year following the study. Precipitins to A. flavus may be related to heavy environmental exposure possibly leading to aflatoxin exposure which may contribute to development of malignancy through immunosuppressive effects.