Immunological characterization of a gammadelta T-cell stimulatory ligand on autologous monocytes

Bovine gammadelta T cells are stimulated to proliferate by autologous monocytes. This is referred to as the autologous mixed leucocyte reaction (AMLR). It has been shown previously that the stimulatory component is constitutively expressed on the monocyte plasma membrane and is a protein or has a protein moiety. Here we showed that gammadelta T-cell responses to the monocytes requires interaction with the T-cell receptor because Fab1 fragments of a monoclonal antibody (mAb) that reacts with the delta chain of the T-cell receptor blocked proliferation in the AMLR. Monocyte molecules involved in stimulation were also characterized further by biochemical and immunological methods. A mAb, named M5, was generated by immunizing mice with bovine monocytes and shown to block the ability of monocytes to stimulate in the AMLR. Treatment of monocytes or monocyte membranes with high salt, chelating agents or phospholipase C did not affect their ability to stimulate gammadelta T-cell proliferation or reactivity with mAb M5 indicating the ability of monocytes to stimulate does not involve peripheral membrane components or a glycosyl-phosphatidylinsositol (GPI)-anchored components. Hence it was concluded that the stimulation occurred as a result of intergral membrane proteins including that recognized by mAb M5. The ligand for mAb M5 was on all bovine monocytes and to a lower level on granulocytes but not on lymphocytes. MAb M5 also reacted with sheep monocytes but not with human monocytes or murine macrophages, in agreement with a previous reports that sheep monocytes but not human or mouse mononuclear phagocytes have the capacity to stimulate bovine gammadelta T cells in in vitro cultures. The level of expression of the M5 ligand was not altered by gamma-irradiation or culture of monocytes with lipopolysaccharide but it was decreased following culture with interferon-gamma-containing cell culture supernatants.     

Rapid identification and antibiotic susceptibility testing of Salmonella enterica serovar Typhi isolated from blood: implications for therapy

The turnaround time (TAT) for Salmonella enterica serovar Typhi identification and reporting of the antibiotic susceptibility profile was determined for 391 cases of typhoid fever, using the lysis direct plating or lysis centrifugation method of blood culture along with rapid antimicrobial susceptibility testing. The TAT was more rapid (TAT for 90% of the patients [TAT(90)] = 30 h; TAT(100) 相似文献   

Chromium concentrations in serum, blood clot and urine from patients following total hip arthroplasty

Chromium released from implant alloys may be incorporated into organometallic complexes as Cr3+ [Cr(III)] or CR6+[Cr(VI)]. Since Cr(VI) is far more biologically active than Cr(III), there is considerable interest in identifying the valence state that predominates in corrosion products, either in vitro or in vivo. It is known that erythrocytes display a unidirectional uptake of Cr(VI) while effectively excluding Cr(III). Thus it was felt that a study of the chromium content of blood clot, in comparison to chromium concentrations in serum and urine, could shed light on the valency question. Fourteen patients who received conventional polymethylmethacrylate cemented cobalt-chromium alloy/ultra high molecular weight polyethylene total hip replacements as well as seven control patients who underwent orthopaedic procedures without implantation were studied. Blood and urine specimens were obtained preoperatively, post-operatively and, for total hip patients, at routine early follow up. Chromium content was determined by electrothermal atomic absorption spectroscopy. A significant post-operative rise in serum chromium content was observed for total hip replacement patients, as previously reported, but not for control patients. Unexpected day-to-day variations in clot chromium content, without significant increases, were also observed. Longer time studies are required to determine chromium valence states in corrosion products in this model.     

Hepatitis B infection in Vietnamese families

The occurrence of hepatitis B infection as measured by sensitive serological tests for HBsAg, HBeAg and hepatitis B-specific antibodies was studied in Vietnamese refugee families. HBsAg was found in 10% of 301 children studied. Totally 74% of all HBsAg-positive children had an HBsAg-positive mother or father and an additional 7% had a positive sibling. The distribution of these cases indicated that the risk of HBs-antigenemia was increased 11-fold for those who had an HBsAg-positive mother compared with all other children. The presence of HBeAg in the HBsAg-positive parents was associated with a threefold higher risk of HBs-antigenemia in children as compared with the presence of anti-HBe. It was thus documented that HBV in this population is spread primarily by intrafamilial routes and prophylactic measures within risk families should largely be able to control the appearance of new HBsAg carriers.     

Births of normal daughters after MicroSort sperm separation and intrauterine insemination, in-vitro fertilization, or intracytoplasmic sperm injection

The world's first deliveries of normal babies after use of flow cytometric separated human sperm cells (MicroSort) for preconception gender selection are reported. Offspring were of the desired female gender in 92.9% of the pregnancies. Most of these pregnancies and births were achieved after simple intrauterine insemination.      

Detection of chromosomes and estimation of aneuploidy in human spermatozoa using fluorescence in-situ hybridization

The development and application of fluorescence in-situ hybridization (FISH) has opened the way for comprehensive studies on numerical chromosome abnormalities in human spermatozoa. FISH can be rapidly applied to large numbers of spermatozoa and thus overcomes the major limitation of karyotyping spermatozoa after penetration of zona-free hamster oocytes. The simultaneous hybridization of two or more chromosome-specific probes to spermatozoa and subsequent detection of the bound probes using different fluorescent detection systems enables two or more chromosomes to be localized simultaneously in the same spermatozoon and provides a technique for undertaking reasonable estimates of aneuploidy. The most commonly used probes are those which bind to the centromeric region of specific chromosomes. Most studies to date have concentrated on estimating aneuploidy in spermatozoa from normospermic men, although reports are beginning to appear on aneuploidy in spermatozoa from subfertile and infertile men. Multi- probe FISH studies have generally reported disomy (hyperhaploidy) estimates of 0.05-0.2% per chromosome. There is preliminary evidence that some chromosomes such as X, Y and 21 are predisposed towards higher rates of non-disjunction during spermatogenesis. There are also suggestions of inter-donor variability in aneuploidy frequencies for specific chromosomes, although this requires confirmation in larger studies. While FISH is clearly a powerful technique that has many applications in reproductive medicine, it must also be realized that it does have limitations and the technology itself is still evolving and has yet to be fully validated on spermatozoa.      

Avian cryptococcosis.

Clinical and laboratory findings in 15 unreported cases of avian cryptococcosis from Australia were collated and contrasted with 11 cases recorded in the literature. Cryptococcus species produced localized invasive disease of the upper respiratory tract of captive parrots living in Australia. This resulted in signs referable to mycotic rhinitis or to involvement of structures contiguous with the nasal cavity, such as the beak, sinuses, choana, retrobulbar space and palate. Parrots of widely differing ages were affected and of the seven birds for which sex was determinable, six were male. Cryptococcus bacillisporus (formerly C. neoformans var. gattii) accounted for four of five infections in which the species or variety was determinable, suggesting that exposure to eucalyptus material may be a predisposing factor. In these cases, Cryptococcus appeared to behave as a primary pathogen of immunocompetent hosts. One tissue specimen was available from an Australian racing pigeon with minimally invasive subcutaneous disease; immunohistology demonstrated a C. neoformans var. grubii (formerly C. neoformans var. neoformans serotype A) infection, presumably subsequent to traumatic inoculation of yeast cells into the subcutis. Two similar cases had been reported previously in pigeons domiciled in America. Data for parrots, one pigeon and other birds studied principally in America and Europe (and likely infected with C. neoformans) suggested a different pattern of disease, more suggestive of opportunistic infection of immunodeficient hosts. In this cohort of patients, the organism was not restricted to cool superficial sites such as the upper respiratory tract or subcutis. Instead, infections typically penetrated the lower respiratory tract or disseminated widely to a variety of internal organs. Finally, three captive North Island brown kiwis, one residing in Australia, the other two in New Zealand, died as a result of severe diffuse cryptococcal pneumonia (two cases) or widely disseminated disease (one case). C. bacillisporus strains were isolated from all three cases, as reported previously for another kiwi with disseminated disease in New Zealand.     

Nucleated erythrocytes in maternal blood: quantity and quality of fetal cells in enriched populations

The discovery of nucleated erythrocytes in maternal circulationprovides a potential source for non-invasive prenatal diagnosis.We have evaluated the use of a three-stage procedure to determinethe number of cells that are of fetal rather than maternal origin.First, monoclonal antibodies specific for CD45 and CD14 wereused in conjunction with a magnetic (MACS) column to depleteunwanted leukocytes from maternal blood. This was followed bya positive MACS enrichment for nucleated erythrocytes, usingan anti-CD71 (transferrin receptor) monoclonal antibody. Todiscriminate between fetal nucleated erythrocytes and thoseof maternal origin, enriched fractions were simultaneously stainedwith an anti-fetal haemoglobin (HbF) antibody and hybridizedwith probes specific for X and Y chromosomes. Samples were thensubjected to blind analysis along with negative control samplesfrom non-pregnant volunteers. Using this dual analysis, we wereable to determine that less than one nucleated erythrocyte perml of maternal blood was of fetal origin. Small numbers of thesefetal cells were found in 87.5% of pregnancies, ranging from6 to 35 weeks gestational age. Comparison of HbF and X/Y probedata also suggests that the fetal cells are less suitable forfluorescence in-situ hybridization (FISH) analysis than similarpreparations from other sources. cell separation methods/fluorescence in-situ hybridization/hereditary diseases/polymerase chain reaction/pregnancy     

Rabbit antisera to the variable region domains of an anti-alpha(1----6) dextran using E. coli-produced VL and VH fusion proteins as immunogens.

Bacteria were engineered for the expression of mouse immunoglobulin light chain variable region (VL) and heavy chain variable region (VH) fusion proteins. cDNAs encoding the VL and VH of anti-alpha(1----6)dextran hybridoma protein 19.22.1 were inserted into the pATH 10 prokaryotic expression vector downstream of trp operon sequences. V domains joined to approximately 330 amino acids of the trp E gene product encoded by the expression plasmids accumulated at high levels in E. coli. In addition, the VL domain was expressed with a 15 amino acid extension at low levels in lon mutant bacteria. The trp E-VL and trp E-VH proteins were used to raise antisera in rabbits and the V specificity of the sera demonstrated.     

A multimedia database system for thermal ablation therapy of brain tumors

A prototype multimedia medical database is described for supporting thermal ablation therapy of brain tumors. Its design is motivated by the major need to manage and access multimedia information on the progress and reaction of tumors to various therapy protocols. The database links images to patient data in a way that permits the user to view and query medical information using alphanumeric, temporal, and feature-based predicates. Visualization programs permit the user to view or annotate the query results in various ways. These results support the wide variety of data types and presentation methods required by neuroradiologists to manage thermal ablation therapy data. The database satisfactorily meets the requirements defined by thermal ablation therapy. A similar approach is being undertaken for supporting different therapies of other types of tumors, thus showing the generality of our approach.