Human TLR-7-, -8-, and -9-mediated induction of IFN-alpha/beta and -lambda Is IRAK-4 dependent and redundant for protective immunity to viruses

Five TLRs are thought to play an important role in antiviral immunity, sensing viral products and inducing IFN-alpha/beta and -lambda. Surprisingly, patients with a defect of IRAK-4, a critical kinase downstream from TLRs, are resistant to common viruses. We show here that IFN-alpha/beta and -lambda induction via TLR-7, TLR-8, and TLR-9 was abolished in IRAK-4-deficient blood cells. In contrast, IFN-alpha/beta and -lambda were induced normally by TLR-3 and TLR-4 agonists. Moreover, IFN-beta and -lambda were normally induced by TLR-3 agonists and viruses in IRAK-4-deficient fibroblasts. We further show that IFN-alpha/beta and -lambda production in response to 9 of 11 viruses tested was normal or weakly affected in IRAK-4-deficient blood cells. Thus, IRAK-4-deficient patients may control viral infections by TLR-3- and TLR-4-dependent and/or TLR-independent production of IFNs. The TLR-7-, TLR-8-, and TLR-9-dependent induction of IFN-alpha/beta and -lambda is strictly IRAK-4 dependent and paradoxically redundant for protective immunity to most viruses in humans.     

Acute pulmonary toxicity of inhaledβ-1,3-glucan and endotoxin

The number of inflammatory cells was studied in lung walls and airways after inhalation of endotoxin or -1,3-glucan. In the water unsoluble form, -1,3-glucan caused a delayed response in terms of a decrease in macrophages and lymphocytes in the lung wall, 1 to 7 days after exposure but no invasion of neutrophils into the airways. When solubilized in 0.02 N NaOH, the cell response was the same as that observed after exposure to endotoxin.     

Refined genetic mapping of autosomal recessive chronic distal spinal muscular atrophy to chromosome 11q13.3 and evidence of linkage disequilibrium in European families

Chronic distal spinal muscular atrophy (Chronic DSMA, MIM (*)607088) is a rare autosomal recessive disorder characterized by a progressive motor weakness and muscular atrophy, predominating in the distal parts of the limbs. A form of Chronic DSMA gene has been previously mapped to chromosome 11q13 in the 10.3 cM interval defined by loci D11S1889 and D11S1321. By linkage analysis in 12 European Chronic DSMA families, we showed that a disease gene maps to chromosome 11q13.3 (Z(max)=6.66 at theta=0.00 at the DSM4 locus) and suggested that this condition is genetically homogeneous. Recombination events allowed us to reduce the genetic interval to a 2.6 cM region, telomeric to the IGHMBP2 gene, excluding this gene as the disease causing gene in Chronic DSMA. Moreover, partial linkage disequilibrium was found between three rare alleles at loci D11S1369, DSM4 and D11S4184 and the mutant chromosome in European patients. Analysis of the markers at these loci strongly suggests that most Chronic DSMA chromosomes are derived from a single ancestor. Refinement of the Chronic DSMA locus will hopefully allow to test candidate genes and lead to identification of the disease-causing mutations.     

A PCR–restriction fragment length polymorphism assay to genotype human metapneumovirus

Human metapneumovirus (hMPV) genotypes A and B show epidemiological and probably clinical differences. This report describes a fast and simple PCR–restriction fragment length polymorphism (PCR-RFLP) assay, involving digestion of the fusion protein gene with Tsp 509I, that allows lineages A1, A2, B1 and B2 to be distinguished. The assay should help in elucidating the epidemiology of hMPV, and possibly in predicting the severity of clinical infection.     

Effect of cumulus cell mass and follicle quality on in-vitro maturation of cynomolgus monkey oocytes

Cynomolgus monkey oocytes were recovered from healthy or atreticfollicles > 1000 µm in diameter at day 8 of gonadotrophinstimulated cycles and cultured in vitro, cumulus enclosed orcumulus free, for 2 days. Germinal vesicle breakdown (GVBD)occurred in 26.7% of healthy cumulus enclosed oocytes (n= 60)compared to 52.6% of atretic cumulus enclosed oocytes (n = 38).The mechanical removal of the cumulus cell mass increased theGVBD rate of the healthy oocytes (56.5%, n = 23) and acceleratedthe passage of the atretic oocytes (n = 23) from metaphase I(4.3%) to metaphase II (47.8%). In the healthy primate follicle,the dktyate stage could be maintained by aninhibitory substancesecreted by the cumulus; foUicular atresia could either decreasethe synthesis of this substance and/or induce the metabolismof a stimulatory substance.     

Histological detection of minimal metastatic involvement in axillary sentinel nodes: a rational basis for a sensitive methodology usable in daily practice.

There is no consensus method for the histological analysis of axillary sentinel nodes (SN). This study aimed to (1) assess the rate of occult metastases in SN using large serial sectioning and immunohistochemistry (IHC), (2) evaluate whether occult metastases were predictive of metastases in the downstream axillary nodes, and (3) specify a methodology of analysis of SN that could be both sensitive and applicable in daily practice. One hundred three patients with breast carcinoma underwent SN biopsy and then axillary dissection. SN free of tumor at standard examination of one section were sectioned at six levels (150-microm intervals) and immunostained for cytokeratin. The number and localization of labeled metastatic cells (occult metastases) were recorded. In 29 of the 103 patients (28%), SN were found to be metastatic after standard examination. The SN of the remaining 74 patients were further analyzed using IHC. Occult metastases were detected in 35 of these patients (47.3%), leading to an overall SN involvement rate of 62% (29+35/103). In 33 of these 35 cases, the plurality and the dispersion of the immunostained cells implied that the screening of only 3 of the 6 levels would have led to the detection of diagnostic positive events. Only one of the 35 patients (2.8%) with occult metastases showed metastatic lymph node in the downstream axilla. In our series of axillary SN, the analysis of one standard histologic section and, when negative, of only three additional sections after IHC revealed >60% of metastasis or occult metastasis. Metastasis detected by standard analysis had a high predictive value of downstream node metastasis, whereas the predictive value of occult metastasis revealed by IHC was poor. The clinical significance of occult metastases in SN needs to be specified by long-term follow-up analysis.     

Double-blind placebo-controlled study of loratadine, mequitazine, and placebo in the symptomatic treatment of seasonal allergic rhinitis

Loratadine is a long-acting H1 antagonist devoid of anticholinergic and sedative effects. A double-blind, placebo-controlled, parallel-group study was performed in 69 patients to compare efficacy and safety of loratadine and mequitazine. Patients allergic to grass pollens were randomly assigned to one of the three treatment groups and followed up to 2 weeks during the peak of the pollen season. Symptoms of allergic rhinitis were evaluated at baseline and after 3, 7, and 14 days of treatment by the physician with patients rating their response daily on diary cards. Both loratadine and mequitazine induced a significant relief of nasal symptoms when these were compared to placebo. Loratadine was found to be significantly superior to placebo after 3 days of treatment, whereas a significant improvement was only observed after 7 days in patients treated with mequitazine. For nonnasal symptoms, none of the two anti-H1 antagonist induced a significant improvement, and this lack of effect may be related to low symptoms at baseline. Loratadine did not induce more side effects than placebo. Loratadine can be considered to be an effective and safe anti H1 histamine with a rapid onset of action.     

Transformation of the cultivated mushroom Agaricus bisporus (Lange) using T-DNA from Agrobacterium tumefaciens

Agrobacterium tumefaciens is known to transfer parts of its tumor-inducing plasmid, the T-DNA, to plants, yeasts and filamentous fungi. We have used this system to transform germinating basidiospores and vegetative mycelium of a commercial strain of the cultivated basidiomycete Agaricus bisporus. Analysis of transformants shows that the T-DNA integrates at random sites into the host genome and that the selection marker is stable during mitosis and meiosis. The Agrobacterium system allows the transformation of both homokaryons and heterokaryons of A. bisporus. Also, both karyotypes of an heterokaryon can be transformed simultaneously. Furthermore, this is the first report on the transformation of vegetative mycelium of a commercial strain of A. bisporus. Received: 6 June 2000 / Accepted: 10 October 2000