[Usefulness of a Newly Developed Immunochromatographic Assay Kit for the Detection of Respiratory Syncytial Virus].

We evaluated the usefulness of IMMUNOCATCH-RSV (Eiken chemical Co., Ltd.) (IC-A), a newly developed immunochromatographic assay kit for detection of respiratory syncytial virus (RSV). For the clinical study, 210 nasal swabs and 134 nasopharyngeal aspirates were collected from pediatric patients with acute respiratory tract infections in 2013. Three immunochromatographic assay kits (IC-A, IC-B and IC-C), and the RT-PCR method were used for the detection of RSV. The detection times for IC-A, IC-B and IC-C were 8, 15 and 10 minutes, respectively. The positive rates for IC-A using nasal swabs and nasopharyngeal aspirates were 33.8% and 35.8%, respectively. For the nasal swab specimens, the total concordance rates of RT-PCR with IC-A, IC-B and IC-C were 96.2% (202/210), 89.5% (188/210), and 90.5% (143/158), respectively. As for the nasopharyngeal aspirates, the total concordance rates of RT-PCR with IC-A, IC-B and IC-C were 96.3% (129/134), 94.0% (125/133), and 97.7% (130/133), respectively. The minimum detection concentration of IC-A was 3.0 x 10(2) TCID50/mL for the RSV subgroup A strain, and 7.5 x 10 TCID50/mL for the RSV subgroup B strain. In conclusion, the current data indicate that IC-A is a useful kit for more rapid and accurate detection of RSV infection.

Detection of antibodies against fimbria type 3 (Fim3) is useful diagnostic assay for pertussis.

Isolation of Bordetella pertussis and detection of the pertussis genome are not always successful because of low bacterial loads in adult patients with pertussis. Antibodies against pertussis toxin (PT) are measured but have low sensitivity in vaccinated subjects. There is no reliable diagnostic method at present. In this study, a fluorescent-EIA against several pertussis antigens and genome detection were investigated to establish clinical laboratory diagnostic methods for pertussis. The study was conducted in an outpatient clinic between September 2007 and 2013. Subjects consisted of 209 patients including adults suspected of pertussis and 35 staff members of the clinic. Loop-mediated isothermal amplification (LAMP) was performed to detect the pertussis genome in 5' UTR of the pertussis toxin (PT) gene. The catalytic region of the adenylate cyclase toxin (catACT), C-terminal of filamentous hemagglutinin (cFHA), and type 3 fimbria (Fim3) were selected, which are not pertussis vaccine component. Conventional PT and FHA antibodies were examined together with type 2 fimbria (Fim2) antibodies, and these are vaccine antigens. Pertussis DNA was detected in 23 (11%) out of 209. Detection sensitivity was high in young infants. Antibodies against Fim3 showed a higher positive rate in all age groups. Staff members at the pediatric outpatient clinic showed serological booster responses in Fim2 and Fim3 antibodies more sensitively than those in PT antibodies during outbreaks. LAMP was useful for detecting the pertussis genome in young infants, whereas a serological assay for fluorescent-EIA against Fim2 and Fim3 was preferable for adolescents and adults.

Identification and characterization of polymorphic variations of the ataxia telangiectasia mutated (ATM) gene in childhood Hodgkin disease.

There are conflicting reports about the involvement of single nucleotide polymorphisms (SNPs) of the ataxia telangiectasia mutated (ATM) gene with cancer, and the consequences of these SNPs for ATM function remain unclear. We therefore sought to identify SNPs of the ATM gene in pediatric Hodgkin disease (HD) and to analyze ATM function in cells from patients with these SNPs. We have identified SNPs of the ATM gene in 5 of 14 children (S1455R, n = 1; H1380Y, n = 1; N1650S, n = 2; and I709I, n = 1). One patient had nonsense-associated altered splicing of the ATM gene. Lymphoblastoid cell lines expressing the S1455R and N1650S exhibited defective ATM-mediated p53 phosphorylation and Chk2 activation; cells expressing the H1380Y exhibited defective c-Abl activation after X-irradiation. Expression of the N1650S in ATM-null fibroblasts conferred only partial hyperradiosensitivity. Furthermore, the introduction of N1650S ATM into U2OS cells, which express wild-type ATM, showed reduced p53-Ser15 phosphorylation, suggesting a dominant-negative effect of the N1650S over the wild-type ATM protein. We conclude that the rare polymorphic variants of the ATM gene that we identified in children with HD encode functionally abnormal proteins, and we discuss the possible genetic risk factors for childhood HD.

Missense mutation and defective function of ATM in a childhood acute leukemia patient with MLL gene rearrangement.

The possible involvement of germline mutation of the ataxia telangiectasia mutated (ATM) gene in childhood acute leukemia with mixed lineage leukemia (MLL) gene rearrangement (MLL(+)) was investigated. Of the 7 patients studied, 1 showed a germline missense ATM mutation (8921C>T; Pro2974Leu), located in the phosphatidylinositol-3 (PI-3) kinase domain. In reconstitution assays, the ATM mutant 8921T could only partially rescue the radiosensitive phenotype of AT fibroblasts, and in an in vitro kinase assay, it showed a defective phosphorylation of p53-Ser15. Furthermore, the introduction of 8921T in U2OS cells, characterized by a normal ATM/p53 signal transduction, caused a significant reduction of in vivo p53-Ser15 phosphorylation, suggesting a dominant-negative effect of the mutant ATM over the wild-type protein. Our finding in this patient suggests that altered function of ATM plays some pathogenic roles in the development of MLL(+) leukemia.