Global distribution of the CCR5 gene 32-basepair deletion.

A mutant allele of the beta-chemokine receptor gene CCR5 bearing a 32-basepair (bp) deletion (denoted delta ccr5) which prevents cell invasion by the primary transmitting strain of HIV-1 has recently been characterized. Homozygotes for the mutation are resistant to infection, even after repeated high-risk exposures, but this resistance appears not to be total, as isolated cases of HIV-positive deletion homozygotes are now emerging. The consequence of the heterozygous state is not clear, but it may delay the progression to AIDS in infected individuals. A gene frequency of approximately 10% was found for delta ccr5 in populations of European descent, but no mutant alleles were reported in indigenous non-European populations. As the total number of non-European samples surveyed was small in comparison with the Europeans the global distribution of this mutation is far from clear. We have devised a rapid PCR assay for delta ccr5 and used it to screen 3,342 individuals from a globally-distributed range of populations. We find that delta ccr5 is not confined to people of European descent but is found at frequencies of 2-5% throughout Europe, the Middle East and the Indian subcontinent (Fig. 1). Isolated occurrences are seen elsewhere throughout the world, but these most likely represent recent European gene flow into the indigenous populations. The inter-population differences in delta ccr5 frequency may influence the pattern of HIV transmission and so will need to be incorporated into future predictions of HIV levels.

DNA methylation and expression of estrogen receptor alpha in fathead minnows exposed to 17α-ethynylestradiol.

The gene expression response thought to underlie the negative apical effects resulting from estrogen exposure have been thoroughly described in fish. Although epigenetics are believed to play a critical role translating environmental exposures into the development of adverse apical effects, they remain poorly characterized in fish species. This study investigated alterations of DNA methylation of estrogen receptor alpha (esr1) in brain and liver tissues from 8 to 10 month old male fathead minnows (Pimephales promelas) after a 2d exposure to either 2.5 ng/L or 10 ng/L 17α-ethynylestradiol (EE2). Changes in the patterns of methylation were evaluated using targeted deep sequencing of bisulfite treated DNA in the 5' region of esr1. Methylation and gene expression were assessed at 2d of exposure and after a 7 and 14d depuration period. After 2d EE2 exposure, males exhibited significant demethylation in the 5' upstream region of esr1 in liver tissue, which was inversely correlated to gene expression. This methylation pattern reflected what was seen in females. No gene body methylation (GBM) was observed for liver of exposed males. Differential methylation was observed for a single upstream CpG site in the liver after the 14d depuration. A less pronounced methylation response was observed in the upstream region in brain tissue, however, several CpGs were necessarily excluded from the analysis. In contrast to the liver, a significant GBM response was observed across the entire gene body, which was sustained until at least 7d post-exposure. No differential expression was observed in the brain, limiting functional interpretation of methylation changes. The identification of EE2-dependent changes in methylation levels strongly suggests the importance of epigenetic mechanisms as a mediator of the organismal response to environmental exposures and the need for further characterization of the epigenome. Further, differential methylation following depuration indicates estrogenic effects persist well after the active exposure, which has implications for the risk posed by repeated exposures..

Infusion of the allogeneic cell line NK-92 in patients with advanced renal cell cancer or melanoma: a phase I trial.

BACKGROUND: Renal cell cancer and malignant melanoma are two types of cancer that are responsive to immunotherapy. In this phase I dose-escalation study, the feasibility of large-scale expansion and safety of administering ex vivo-expanded NK-92 cells as allogeneic cellular immunotherapy in patients with refractory renal cell cancer and melanoma were determined. METHODS: Twelve patients (aged 31-74 years) were enrolled, three per cohort at cell dose levels of 1x10(8)/m(2), 3x10(8)/m(2), 1x10(9)/m(2) and 3x10(9)/m(2). One treatment course consisted of three infusions. Eleven patients had refractory metastatic renal cell cancer; one patient had refractory metastatic melanoma. RESULTS: The NK-92 cells were expanded in X-Vivo 10 serum-free media supplemented with 500 U/mL Proleukin recombinant human interleukin-2 (rhIL-2), amino acids and 2.5% human AB plasma. Final yields of approximately 1x10(9) cells/culture bag (218-250xexpansion) over 15-17 days were achievable with >or=80% viability. Infusional toxicities of NK-92 were generally mild, with only one grade 3 fever and one grade 4 hypoglycemic episode. All toxicities were transient, resolved and did not require discontinuation of treatment. One patient was alive with disease at 4 years post-NK-92 infusion. The one metastatic melanoma patient had a minor response during the study period. One other patient exhibited a mixed response. DISCUSSION: This study establishes the feasibility of large-scale expansion and safety of administering NK-92 cells as allogeneic cellular immunotherapy in advanced cancer patients and serves as a platform for future study of this novel natural killer (NK)-cell based therapy.

A computer simulation study of VNTR population genetics: constrained recombination rules out the infinite alleles model.

Extensive allelic diversity in variable numbers of tandem repeats (VNTRs) has been discovered in the human genome. For population genetic studies of VNTRs, such as forensic applications, it is important to know whether a neutral mutation-drift balance of VNTR polymorphism can be represented by the infinite alleles model. The assumption of the infinite alleles model that each new mutant is unique is very likely to be violated by unequal sister chromatid exchange (USCE), the primary process believed to generate VNTR mutants. We show that increasing both mutation rates and misalignment constraint for intrachromosomal recombination in a computer simulation model reduces simulated VNTR diversity below the expectations of the infinite alleles model. Maximal constraint, represented as slippage of single repeats, reduces simulated VNTR diversity to levels expected from the stepwise mutation model. Although misalignment rule is the more important variable, mutation rate also has an effect. At moderate rates of USCE, simulated VNTR diversity fluctuates around infinite alleles expectation. However, if rates of USCE are high, as for hypervariable VNTRs, simulated VNTR diversity is consistently lower than predicted by the infinite alleles model. This has been observed for many VNTRs and accounted for by technical problems in distinguishing alleles of neighboring size classes. We use sampling theory to confirm the intrinsically poor fit to the infinite alleles model of both simulated VNTR diversity and observed VNTR polymorphisms sampled from two Papua New Guinean populations.

Characterization of a culture-derived CD15+CD11b- promyelocytic population from CD34+ peripheral blood cells.

Selected CD34+ cells from mobilized apheresis products were cultured in serum-free or serum-containing media supplemented with granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), and stem cell factor (SCF; c-kit ligand). We examined the emergence of a CD15+CD11b- population, which appeared morphologically to be promyelocytes. This CD15+CD11b- population can be further expanded in culture into morphologically mature granulocytes. In an attempt to characterize this culture-derived CD15+CD11b- promyelocytic population, single cells were clone sorted into wells of a Terasaki plate containing various growth factors. We compared the growth factor requirements and kinetics of this apheresis culture-derived CD15+CD11b- population to the CD15+CD11b- population from fresh bone marrow samples. Our studies indicate that the CD15+CD11b- promyelocytic population from bone marrow and blood are equivalent in their ability to proliferate and in their requirements for growth factors. The CD15+CD11b- population in vitro shows a high proliferative capacity when compared with the other CD15/CD11b populations (CD15-CD11b-, CD15+CD11b+, CD15-CD11b+). Thus, we can manipulate CD34+ cells in vitro to proliferate and differentiate toward a mature neutrophil lineage. The CD15+CD11b- promyelocytic population derived from this culture may represent the most effective cultured cell population for therapeutic reduction of neutropenia in vivo based on both its stage of differentiation and its proliferative potential.

Global distribution of the CCR2-64I/CCR5-59653T HIV-1 disease-protective haplotype.

OBJECTIVES: Several natural polymorphisms in the genes for the human CC-chemokine receptors CCR5 and CCR2 are associated with HIV-1 disease. The CCR2-64I genetic variant [a G to A substitution resulting in a valine (V) to isoleucine (I) change at position 64] is in strong linkage disequilibrium with a mutation within the CCR5 regulatory region (CCR5-59653T). Individuals with two CCR2-64I alleles are not resistant to sexual transmission of HIV-1, but progress significantly more slowly to HIV-1 disease. It is therefore important to determine the global distributions of CCR2-64I and CCR5-59653T genetic variants and define the degree of linkage between them. DESIGN AND METHODS: We have developed molecular beacon-based, real-time PCR allele discrimination assays for all three chemokine receptor mutations, and used these spectral genotyping assays to genotype 3923 individuals from a globally distributed set of 53 populations. RESULTS: CCR2-64I and CCR5-59653T genetic variants are found in almost all populations studied: their allele frequencies are greatest (approximately 35%) in Africa and Asia but decrease in Northern Europe. We confirm that CCR2-64I is in strong linkage disequilibrium with CCR5-59653T (96.92% of individuals had the same genotype for both CCR2-64I and CCR5-59653T polymorphisms). CONCLUSIONS: The greater geographical distribution of the CCR2-64I/CCR5-59653T haplotype compared with that of CCR5-delta32 suggests that it is a much older mutation whose origin predates the dispersal of modern humans.

hOGG1 Ser326Cys polymorphism and lung cancer susceptibility.

The human homologue of the yeast OGG1 gene, hOGG1, has been cloned, and its genetic structure has been determined. Several polymorphisms in the hOGG1 gene were detected in the Japanese populations, and among them, the Ser-Cys polymorphism at codon 326 has been shown to have a functional difference in complementation of mutant Escherichia coli that is defective in the repair of 8-hydroxyguanine. Activity in the repair of 8-hydroxyguanine is greater in hOGG1-Ser326 protein than in hOGG1(326) protein. Because many environmental carcinogens produce 8-hydroxyguanine residue and mismatching to this modified base potentially causes oncogenic mutations, the capacity to repair these lesions can be involved in cancer susceptibility in human beings. We, therefore, examined allele distributions of the Ser326Cys polymorphism in a case-control study of male lung cancer in Okinawa. The analyses based on 241 cases and 197 hospital controls disclosed the following findings. (a) Those with the Cys/Cys genotype were at an increased risk of squamous cell carcinoma and nonadenocarcinoma compared to those with the Ser/Cys and those with the Ser/Ser genotypes combined. The odds ratios adjusted for age and smoking history were 3.01 (95% confidence interval, 1.33-6.83) and 2.18 (95% confidence interval, 1.05-4.54), respectively. (b) The odds ratios for other histological subtypes of lung cancer or those in total were not significant. Those for Cys/Cys or Ser/Cys genotype against Ser/Ser did not reach statistical significance in any cell type. (c) The distributions of this polymorphism varied for different populations (Chinese, Japanese, Micronesians, Melanesians, Hungarians, and Australian Caucasians), with much less prevalence of Cys allele in the latter three populations. Although our sample size was limited, these results indicate that the Ser326Cys variant may be related to squamous cell lung cancer susceptibility. The Cys/Cys genotype appears to be more susceptible to squamous cell carcinoma, although the risk is less than that previously reported to be associated with the CYP1A1 gene. Further studies are needed to assess the importance of the interpopulation variation to cancer susceptibility.

Recognition of temporally structured activity in spontaneously discharging neurons in the somatosensory cortex in waking cats.

We describe a method to automate the detection and analysis of structured neuronal activity obtained in relatively non-restrictive experiments in awake animals. Several different, regularly occurring, discharge patterns consisting of groups of spikes were identified in extracellular recordings from the somatosensory cortex of awake cats. The introduction of an interspike interval threshold made it possible to segregate these bursts from single spikes. The threshold interval was obtained from the modal interval in high-resolution autocorrelograms (up to 0.1 ms/bin) of the spontaneous neural activity. Single spikes were those separated by intervals greater than the threshold, while those within the group were of less than threshold value. When intervals were arranged and averaged according to their order of occurrence within the burst, four distinctive burst patterns were observed. These four patterns occurred in both normal and deafferented cortex and we believe them to be characteristic of particular cell types, a feature that will be useful for studying such cells in intact cellular networks.

Surgical treatment of thyrotoxicosis: results of 272 operations with special reference to preoperative treatment with anti-thyroid drugs and L-thyroxine.

From 1959 to 1970, 272 operations for thyrotoxicosis were performed. Most of the patients received anti-thyroid drugs and thyroid hormones preoperatively. The patients were continuously followed up. The primary results with low morbidity and no mortality as well as the long term results with a low rate of recurrence and a relatively high incidence of thyroid substitution are discussed. A safe and effective programme for surgical treatment of thyrotoxicosis is described. Anti-thyroid drugs and thyroid hormones should be administered as the method of choice in preparing these patients for surgery.

Ex vivo expansion of natural killer cells for clinical applications.

BACKGROUND: Immunotherapy with NK cells has been limited by the inability to obtain sufficient numbers of pure NK cells suitable for manipulation and expansion. The goal of this study was to isolate CD56(+) cells (CD3(-)/CD56(+), CD3(+)/CD56(+)) and expand them under culture conditions compliant with current good manufacturing practices. METHODS: Magnetic cell-selection technology, using paramagnetic CD56 microbeads and cell selection columns, was used to isolate a CD56(+) population containing both CD3(-)/56(+) NK (60.6+/-10.8%) and CD3(+)/56(+) NK T cells (30.4+/-8.6%) to initiate the expansion studies. The isolated CD56(+) cells were cultured in X-Vivo10 serum-free media supplemented with 10% human AB serum and 500 U/mL recombinant human IL-2 or 500 U/mL IL-2 plus 10 ng/mL recombinant human IL-15 for 14 days. Cultures were fed fresh media and cytokines every 3-4 days, and were evaluated for cell expansion, phenotype, and cytotoxicity at the end of the culture period. RESULTS: Significant expansion of CD56 cells occurred only during the second week of culture. Although an average of two log expansions was observed, there was substantial cell-expansion variability, depending on the donor, and even when the same donor was tested on different occasions. The cytotoxicity of selected and expanded CD56(+) cells at a low E:T ratio was significantly higher than the starting population, but was comparable to non-separated PBMC expanded for 2 weeks under the same conditions. IL-15 (in combination with IL-2) induced higher killing at the 1:1 E:T ratio than IL-2 alone. Since CD3 cells were not depleted upfront, the expansion of CD3(+)CD56(+) cells was 2-3 times that of CD3(-)CD56(+) cells. NK cells that express the FcgammaRIII (CD16) can mediate Ab-dependent cellular cytotoxicity, and can contribute to enhanced efficacy of MAb treatment. Under the given culture conditions, only moderate expansion of CD56(+)/CD3(-)/CD16(+) cells occurred, with the majority of cells being CD56(+)/CD3(+)/CD16(+) cells. DISCUSSION: Our studies suggest that the positive magnetic cell-separation method provides a good basis for obtaining enriched CD56(+) cells but expansion conditions need to be optimized.

VNTR alleles associated with the alpha-globin locus are haplotype and population related.

The human alpha-globin complex contains several polymorphic restriction-enzyme sites (i.e., RFLPs) linked to form haplotypes and is flanked by two hypervariable VNTR loci, the 5' hypervariable region (HVR) and the more highly polymorphic 3'HVR. Using a combination of RFLP analysis and PCR, we have characterized the 5'HVR and 3'HVR alleles associated with the alpha-globin haplotypes of 133 chromosomes, and we here show that specific alpha-globin haplotypes are each associated with discrete subsets of the alleles observed at these two VNTR loci. This statistically highly significant association is observed over a region spanning approximately 100 kb. With the exception of closely related haplotypes, different haplotypes do not share identically sized 3'HVR alleles. Earlier studies have shown that alpha-globin haplotype distributions differ between populations; our current findings also reveal extensive population substructure in the repertoire of alpha-globin VNTRs. If similar features are characteristic of other VNTR loci, this will have important implications for forensic and anthropological studies.

Dynamic gastric response to expansion before and after vagotomy.

The dynamic gastric pressure response to expansion by direct intragastric air insufflation, 30-50 ml/s, was studied in healthy volunteers, non-operated ulcer disease patients, and in patients operated upon with antrectomy, antrectomy and vagotomy, or proximal selective vagotomy. Non-operated individuals accepted gastric expansion without considerable increase of pressure. Antrectomized patients showed a higher basal pressure and a moderate increase of pressure during expansion. Vagotomized patients, including the ones operated upon with proximal selective vagotomy, demonstrated a marked increase of pressure during expansion. The results indicate that vagal denervation of the corpus-fundus part of the stomach is followed by an impairment of gastric resrvoir function.

Comparative studies on the effects of bradykinin and vagal stimulation on motility in the stomach and colon.

The effect of bradykinin on gastric and colonic motility was studied in anaesthetized cats with volume recording devices and compared with the effects of vagal nerve stimulation. When administered intrarterially bradykinin caused a profound and prolonged gastric relaxation. Stimultaneously there was a marked and likewise prolonged colonic contraction. The gastric relaxation closely mimicked the atropine resistant relaxation elicited by vagal nerve stimulation. These effects could not be blocked by antiadrenergic drugs and it is suggested that bradykinin and the unknown transmittor substance(s) released on vagal stimulation act in a similar way on the gastric smooth muscles and that a kinin mechanism may be involved in the vagal response. As regards the colonic motor response it was shown that bradykinin does not reproduce the vagal motility effects on colon smooth muscle but mimicks closely the atropine resistant expulsive contraction elicited by activation of the pelvic nerves.

Vagal gastric relaxation in the dog.

Experiments were performed on anaesthetized dogs. Vagotomy was followed by an increase of gastric tone. The phasic responses of gastric tone to efferent vagal electrical stimulation were not separable in these experiments as they are in cats. Oesophageal distension, however, produced a marked gastric relaxatory response, which, as in cats, was non-cholinergic and non-adrenergic but abolished by vagotomy. This response is suggested to be equivalent to physiological receptive relaxation of the stomach, occurring during food intake.

Gastric relaxatory response to feeding before and after vagotomy.

Experiments were performed on 4 non-anaesthetized dogs with chronic gastric fistulae. Gastric tonus was studied by volume and inflow rate recording at low pressure heads. Gastric tonus was not affected by propranolol or phentolamine. It was markedly reduced by atropine, presumably by blocking excitatory cholinergic nervous activity. Guanethidine induced a marked increase of gastric tonus, presumably by inhibiting sympathetic modulating activity on intramural cholinergic ganglia. Feeding was accompanied by a marked gastric relaxation which was not blocked by any of the drugs mentioned. Vagotomy, however, entirely abolished the gastric relaxatory response to feeding. The findings suggest that gastric receptive relaxation accompanying feeding is mediated via specific relaxatory vagal nerve fibres, which are non-adrenergic and non-cholinergic.