Dendritic cells generated in the presence of GM-CSF plus IL-15 prime potent CD8+ Tc1 responses in vivo

Dendritic cells (DC) comprise a system of professional antigen-presenting cells, which induce the stimulation of very rare antigen-specific naive T cells. DC progenitors can be stimulated to differentiate into immature DC by various growth factors, including GM-CSF and IL-4. Here we show that IL-15, in combination with GM-CSF, is a growth factor for murine DC. Murine bone marrow cells, depleted of T cells, B cells, I-A+ cells and Gr-1+ granulocytes, and cultured in the presence of GM-CSF plus IL-15 (IL-15 DC), yielded DC expressing high levels of CD11c and MHC class II molecules, as well as CD11b. These cells expressed significant levels of CD40, CD80 and CD86, and could stimulate allogeneic CD4+ T cells efficiently. Interestingly, IL-15 DC were far superior to DC generated with GM-CSF plus IL-4 in stimulating allogeneic CD8+ T cells in vitro. Consistent with this, IL-15 DC induced much more potent antigen-specific CD8+ T cell responses with high levels of Th1 cytokines in vivo, compared to DC generated with GM-CSF plus IL-4, or with GM-CSF plus TGF-beta, or with GM-CSF alone. Together, these data suggest that IL-15 promotes the development of DC, which induce potent Th1 and Tc1 responses in vivo. This suggests potential roles for these IL-15 DC cells in the immunotherapy of tumors and infectious diseases.     

National Department of Defense surveillance data for antibiotic resistance and emm gene types of clinical group A streptococcal isolates from eight basic training military sites

Antibiotic resistance and emm gene types were examined from 692 Group A streptococci isolates from eight United States military basic training sites between 1998 and 2001. Macrolide resistance was associated with geographic sites and emm type. These data are useful for vaccine development initiatives and antimicrobial treatment considerations.     

Evolution of resource competition between mutually dependent digital organisms

We study the emergence and dynamics of competing strains of digital organisms in a world with two depletable resources. Consumption of one resource produces the other resource as a by-product, and vice versa. As a consequence, two types of mutually dependent organisms emerge that each prey on the waste product of the other. In the absence of mutations, that is, in a purely ecological setting, the abundances of the two types of organisms display a wide range of different types of oscillations, from regular oscillations with large amplitude to irregular oscillations with amplitudes ranging from small to large. In this regime, time-averaged abundance levels seem to be controlled by the relative fitness of the organisms in the absence of resources. Under mutational pressure, on the other hand, populations evolve that seem to avoid the oscillations of intermediate to large amplitudes. In this case, the relative fitness of the organisms in the presence of resources plays an important role in the time-averaged abundance levels as well.     

Attitudes of subjects at risk and their relatives towards genetic counselling in Huntington''s chorea.

Ninety-two patients suffering from Huntington's chorea (HC) and their spouses, and 91 subjects with an affected parent and their spouses, living in three counties of industrial South Wales, have been studied regarding their knowledge of their inheritance of the disorder. Particular attention was paid to its influence on their attitudes towards child-bearing, telling their children of the risks, and predictive tests. Only 12% of the patients were known to have received professional advice before completing their families, in contrast to 68% of the sample at risk. It is estimated that 82% of the patients and 60% of the subjects at risk had, or might have, restricted their family size had they known in time. The majority found genetic counselling helpful, but did not necessarily wish to alter their child-bearing plans in consequence. It was clear that information provided by the family alone was usually inadequate and that this applied to the present generation at risk as well as to previous generations. It was concluded that the burden of telling children the risks is too great for most parents and that professional help is needed. The long term impact of genetic counselling on the incidence of the disease is impossible to assess without continued monitoring, but preliminary results are encouraging. Attitudes towards a predictive test reflected much conflict: although 56% overall wished to take one, only 40% of those who were parents wished to know if they were at risk of passing the gene on to their children. Few subjects reported severe social stress on learning of their genetic risks, but about one in four reported experiencing significant anxiety.     

Heterogeneity of clara cell glutathione. A possible basis for differences in cellular responses to pulmonary cytotoxicants

Clara-cell populations show a high degree of variation in susceptibility to injury by bioactivated cytotoxicants. Because glutathione (GSH) is critical for detoxification of electrophilic metabolites, heterogeneity in Clara cell GSH levels may lead to a wide range of cytotoxic responses. This study was designed to define the distinct GSH pools within Clara cells, characterize heterogeneity within the population, and examine whether heterogeneity contributes to susceptibility. Using fluorescent imaging combined with high-performance liquid chromatography analysis, semiquantitative measurements were obtained by evaluation of GSH using monochlorobimane and monobromobimane. In steady-state conditions, the GSH measured in isolated cells was in the femtomole range, but varied 4-fold between individual cells. Clara cells analyzed in situ and in vitro confirmed this heterogeneity. The response of these cells to compounds that modulate GSH was also variable. Diethylmaleate depleted GSH, whereas GSH monoethylester augmented it. However, both acted nonuniformly in isolated Clara cells. The depletion of intracellular GSH caused a striking decrease in cell viability upon incubation with naphthalene (NA). The sulfhydryl-binding fluorochrome BODIPY, which colocalized with tetramethylrosamine, a mitochondrial dye, demonstrated by confocal microscopy that cellular sulfhydryls are highest in the mitochondria, next-highest in cytoplasm, and lowest in the nucleus. These pools responded differently to modulators of GSH. We concluded that the steady-state intracellular GSH of Clara cells exists in distinct pools and is highly heterogeneous within the population, and that the heterogeneity of GSH levels corresponds closely to the response of Clara cells to injury by NA.     

A practical approach to fibromyalgia

Fibromyalgia is the name given to a collection of symptoms with no clear physiologic cause, The constellation of symptoms are clearly recognizable as a distinct pathologic entity. The diagnosis is made through clinical observations made by the examiner. Differential diagnosis must include other somatic syndromes as well as disease entities like hepatitis, hypothyroidism, diabetes mellitus, electrolyte imbalance, multiple sclerosis, and cancer. Diagnostic criteria are given as guidelines for the diagnosis, not as absolute requirements. Treatment of this condition remains individualized and relies heavily on having a therapeutic relationship with a provider. Treatment of this syndrome needs to be looked at as an ongoing process. Goal oriented treatment aimed at maintaining specific functions can be directed at helping a patient get restorative sleep, alleviating the somatic pains that ail the patient, keeping a person productive, regulating schedules or through goal oriented agreements made with the patient. Since this syndrome is chronic and may effect all areas of a persons functioning the family and social support system of the person being treated need to be evaluated. Patients often seek alternative medical treatments for this problem including diet therapy, acupuncture, and herbal therapy. Treatment must involve more than just the symptoms presented and the patient can only be treated successfully if they are willing to work at changing their own perceptions, and ways of relating to stressors in their world.     

Analysis of the Virus Population Present in Equine Faeces Indicates the Presence of Hundreds of Uncharacterized Virus Genomes

Virus DNA was isolated from horse faeces and cloned in a sequence-independent fashion. 268 clones were sequenced and 178140 nucleotides of sequence obtained. Statistical analysis suggests the library contains 17560 distinct clones derived from up to 233 different virus genomes. TBLASTX analysis showed that 32% of the clones had significant identity to GenBank entries. Of these 63% were viral; 20% bacterial; 7% archaeal; 6% eukarya; and 5% were related to mobile genetic elements. Fifty-two percent of the virus identities were with Siphoviridae; 26% unclassified phages; 17% Myoviridae; 4% Podoviridae; and one clone (2%) was a vertebrate Orthopoxvirus. Genes coding for predicted virus structural proteins, proteases, glycosidases and nucleic acid-binding proteins were common.     

Oligonucleotide primers designed to differentiate pathogenic pseudomonads on the basis of the sequencing of genes coding for 16S-23S rRNA internal transcribed spacers.

Universal primers targeting conserved sequences flanking the 3' end of the 16S and the 5' end of the 23S rRNA genes (rDNAs) were used to amplify the 16S-23S rDNA internal transcribed spacers (ITS) from eight species of pseudomonads which have been associated with human infections. Amplicons from reference strains of Pseudomonas aeruginosa, Pseudomonas cepacia, Pseudomonas gladioli, Pseudomonas mallei, Pseudomonas mendocina, Pseudomonas pickettii, Pseudomonas pseudomallei, and Xanthomonas maltophilia were cloned from each species, and sequence analysis revealed a total of 19 distinct ITS regions, each defining a unique sequevar with ITS sizes ranging from 394 (P. cepacia) to 641 (P. pseudomallei) bp. Five distinct ITS sequevars in P. cepacia, four in P. mendocina, three in P. aeruginosa, two each in P. gladioli and P. pseudomallei, and one each in P. mallei, P. pickettii, and X. maltophilia were identified. With the exception of one P. cepacia ITS, all ITS regions contained potential tRNA sequences for isoleucine and/or alanine. On the basis of these ITS sequence data, species-specific oligonucleotide primers were designed to differentiate P. aeruginosa, P. cepacia, and P. pickettii. The specificities of these primers were investigated by testing 220 clinical isolates, including 101 strains of P. aeruginosa, 103 strains of P. cepacia, and 16 strains of P. pickettii, in addition to 24 American Type Culture Collection (ATCC) Pseudomonas strains. The results showed that single primer pairs directed at particular ITSs were capable of specifically identifying the ATCC reference strains and all of the clinical isolates of P. aeruginosa and P. pickettii, but this was not the case with several ITS-based primer pairs tested for P. cepacia. This pathogen, on the other hand, could be specifically identified by primer pairs directed against the 23S rDNA.     

Receptivity,rejection and reactivity in female rats following kainic acid and electrolytic septal lesions

Sprague-Dawley rats were ovariectomized and received bilateral sham, electrolytic or kainic acid lesions of the septum. Kainic acid lesions are purported to destroy cell bodies while not appreciably damaging fibers of passage or afferent terminals. Following priming with estradiol benzoate (EB), animals received three consecutive tests of lordosis and rejection behavior. Animals also received six tests of reactivity; one prior to each EB priming regimen and one following each lordosis and rejection test. Reactivity measures included resistance to capture and magnitude and quantity of startle responses. Electrolytic and kainic acid lesions were equivalent in facilitating lordosis. Although both lesions also increased rejection frequency, kainic acid effects were transient and markedly smaller by 60–80%. Reactivity data generally demonstrated significantly higher scores for kainic acid and electrolytic lesions groups and apparently time-dependent decreases in these scores. The results suggest that rejection behavior is not necessarily correlated with either lordosis or hyperreactivity.