Construction and validation of a Parkinson's disease mutation genotyping array for the Parkin gene.

Parkin mutations account for the majority of familial and sporadic early onset Parkinson's disease (EOPD) cases with a known genetic association. More than 100 mutations have been described in the Parkin gene that includes homozygous, compound heterozygous, and single heterozygous mutations. We have designed a Parkin mutation genotyping array (gene chip) that includes published Parkin sequence variants and allows their simultaneous detection. The chip was validated by screening 85 PD cases and 47 controls previously tested for Parkin mutations. Similar genotyping microarrays have been developed for other genetically heterogeneous diseases including age-related macular degeneration. Here, we show the utility of a genotyping array for Parkinson's disease by analysis of 60 subjects from the Genetic Epidemiology of Parkinson Disease (GEPD) study that includes 15 early-onset PD case probands and 45 relatives.     

Peripheral avian yolk assemblage and its persistence in the blastoderm, studied by trypan blue-induced fluorescence

Summary Shortly after subcutaneous or intraperitoneal injection of nontoxic quantities of trypan blue into laying Japanese quails, red fluorescent yolk granules appear in the peripheral ooplasm of their oocytes at the end of the lampbrush stage or subsequently. Later a red fluorescence can be observed in the apical cytoplasm of the granulosa cells. The results obtained by this method confirm our previous results (Callebaut 1974) obtained by autoradiography after ³H-leucine administration and furnish interesting additional data. The trypan blue-induced fluorescence method gives a good indication of the permeability of the oocytal cortex and its derivative the germinal disc. The avian yolk which is, or has been peripherally assembled (primordial, true white and yellow yolk) can be characteristically labelled by the administration of trypan blue. The injection of higher, still nontoxic quantities of trypan blue has a prolonged retarding effect and permits the marking of a broader part of the germinal disc or eventually of the blastoderm which develops from it.     

Detection and characterization of DNA-anti-DNA complexes in a patient with systemic lupus erythematosus.

DNase digestion of SLE serum, with consequent release of bound DNA antibody has been proposed as a method for the direct demonstration of circulating DNA-anti-DNA complexes. In the present studies on the serum of a girl with active SLE nephritis, circulating DNA-anti-DNA complexes were demonstrated at the precise time of relapse of SLE nephritis. Ultracentrifugation showed that these complexes were of low molecular weight.     

Interleukin-6 induced at mucosal surfaces by gram-negative bacterial infection.

Interleukin-6 (IL-6) was produced in response to mucosal and systemic infection of mice with gram-negative bacteria. The IL-6 response was controlled by the lipopolysaccharide gene, Lps; in C3H/HeN mice (Lpsn/Lpsn), the urinary IL-6 levels increased within 30 min after challenge with Escherichia coli, but no response occurred in C3H/HeJ mice (Lpsd/Lpsd). In lipopolysaccharide-responder mice, the levels of local and systemic IL-6 were related to the degree of infection. The urinary response dominated after intravesical challenge, and the serum response dominated after intraperitoneal challenge. The results demonstrate that IL-6 is activated as part of lipopolysaccharide-induced mucosal and systemic responses to gram-negative bacterial infections.     

Induction of T cell proliferation with anti-CD3 switch-variant monoclonal antibodies: effects of heavy chain isotype in monocyte-dependent systems

Monoclonal antibodies (mAb) directed against the CD3 (T3), antigen are able to induce proliferation in resting human T lymphocytes. T cell proliferation only occurs in the presence of monocytes that carry the proper Fc receptor for the mAb used. To further analyze the role of the Fc portion of anti-CD3 mAb in proliferation induction, we isolated, starting from a gamma 1 anti-CD3-producing hybridoma, four heavy-chain isotype switch-variant antibody-secreting clones, producing gamma 2b, gamma 2a, epsilon and alpha, respectively. All variant antibodies recognize the CD3 antigen as determined by immunoprecipitation and cross-blocking experiments. With this series of isotype variant antibodies we were able, in proliferation induction experiments, to confirm the Fc receptor polymorphism for murine IgG2a, IgG2b and IgG1 on human monocytes. Moreover, we found that all 30 donors tested responded to the IgE anti-CD3 antibody, while no IgA responders could be identified. The induction of proliferation by the IgE variant antibody does not require the 72-kDa Fc receptor which is responsible for the interaction with mouse IgG2a. Nonresponsiveness to the IgG1 antibody, but not to the IgG2b or IgA variant antibodies, could be overcome by the addition of exogenous interleukin 2 to the cultures. When the switch-variant antibodies were used to induce IgM synthesis in peripheral blood mononuclear cells only low IgM synthesis was found, with the exception of the IgE variant, which induced excellent T cell help for IgM production.     

A new form of skeletal dysplasia with amelogenesis imperfecta and platyspondyly

We report two patients, born of consanguineous parents, affected by a disorder resulting in mild growth retardation. Hallmarks are amelogenesis imperfecta (absence of the enamel cap) associated with brachyolmia-like anomalies: platyspondyly with short pedicles, narrow intervertebral and interpedicular distances, rectangular-shaped vertebrae with posterior scalloping and herniation of the nuclei, and broad femoral necks. Inheritance appears to be autosomal recessive.     

Co-stimulation of T cells via CD28 inhibits human IgE production; reversal by pertussis toxin.

In lymphocyte cultures, IgE production was achieved by stimulating T cells with anti-CD2 and IL-2. Here we show that anti-CD28, in the presence or absence of IL-2, reduces this IgE production approximately 10-fold. This inhibition of IgE production was almost completely reversed by Pertussis toxin (PT). PT had no effect on IgE production when the cells were stimulated in the absence of anti-CD28. No major effects of PT were found on IgM production. PT had no effect on purified B cells, stimulated with IL-4 and anti-CD40. In the presence of saturating amounts of rIL-4 similar results were obtained, albeit the absolute amounts of IgE produced were higher in all situations. Furthermore, PT-induced IgE production was still dependent on IL-4, as was evident from experiments in which anti-IL-4 was added to the culture. The IgE enhancing effect was dependent on the adenosine diphosphate (ADP)-ribosyltransferase activity of PT, because a mutant molecule lacking this activity was not able to restore anti-CD28-induced inhibition of IgE synthesis. Thus, we show that co-stimulation with anti-CD28 causes an inhibition of T cell-dependent IgE production by B cells, which inhibition can be specifically overcome by PT. An analysis of the molecular pathways underlying this phenomenon may contribute to our understanding of the regulation of IgE synthesis in (patho)physiological conditions.     

Pseudoaminopterin syndrome

We report on a boy with a combination of manifestations reminiscent of aminopterin embryopathy: brachyturricephaly with craniosynostosis, poorly mineralised vault, upslanted palpebral fissures, malar hypoplasia, high-arched palate, micrognathia, thick, abnormal auricles, ASD, minor hand anomalies, growth and mental ratardation. Three convincing cases of “Aminopterin Syndrome Sine Aminopterin” have been reported (the fourth case possibly having the Juberg–Hayward syndrome). Variability and heterogeneity of cases with apparent aminopterin embryopathy are discussed. © 1993 Wiley-Liss, Inc.     

Comparison of the effects of recombinant interleukin 6 and recombinant interleukin 1 on nonspecific resistance to infection

Interleukin 1 (IL 1) is a potent enhancer of nonspecific resistance to infection in mice. Since IL 1 also induces interleukin 6 (IL 6), we tested the hypothesis that IL 6 mediates the effect of IL 1 on nonspecific resistance. In a lethal Pseudomonas aeruginosa infection in granulocytopenic mice, in which 80 ng of recombinant human IL 1 alpha protects against death, IL 6 appeared to be much less effective. Dosages of 8 ng, 80 ng and 320 ng IL 6 did not differ from the control, whereas 800 ng had a marginal protective effect (0.05 less than p less than 0.1). IL 1 and IL 6 did not potentiate each other in animals treated with suboptimal dosages of both cytokines. Numbers of bacteria cultured from the blood, thigh muscle, liver, spleen, and kidney were similar in animals treated with 800 ng IL 6 and in control animals, arguing against activation of microbicidal mechanisms. The serum concentration profile of IL 6 after an i.p. injection of 80 ng IL 1 was similar to that after 80 ng IL 6 i.p. Only minute amounts of IL 1 were detected in serum after an i.p. injection of IL 6. Taken these data together, it appears that increased resistance to infection induced by IL 1 is not mediated by IL 6.