Cytopathogenic cerebrospinal fluid from neurological and psychiatric patients

Cerebrospinal fluids (CSFs) were examined for the presence of a cytopathogenic component by an in vitro assay. No abnormal proteins were detected in CSF which produced cytopathic effects. The cytopathic effect was associated with high-molecular-weight material which was resistant to enzyme treatment. The effect persisted after extensive ultraviolet irradiation. The presence of the cytopathic effect was associated with increased CSF enolase levels.     

The morphology of immune reactions in normal, thymectomized and reconstituted mice: I. The response to sheep erythrocytes

The response to sheep red blood cells has been studied in the lymph nodes draining their site of injection in normal mice, and in thymectomized, irradiated, bone-marrow injected mice with and without a reconstituting thymus graft. By using a chromosome marker to differentiate between cells derived from the bone-marrow and thymus graft it has proved possible to show that the immune response should be thought of in terms of at least two cell populations. Cells of thymic origin are stimulated to mitotic activity in the interfollicular cortex, and their activity precedes both antibody production and morphological signs of activity in the follicular regions. Mitotic divisions of cells of bone-marrow origin reached a peak a day later than did the thymic cells and their activity was sustained. Follicular enlargement and germinal centre production were coincident in time both with antibody production and bone-marrow cell mitotic activity. Lymph nodes of animals lacking a thymic influence showed only minor changes after antigenic stimulation and these were restricted to the follicular regions. There appeared to be only a small quantitative difference between the responses of normal and of reconstituted animals.     

Calibration and performance of a small animal gradient layer calorimeter box

Calorimetry, using the gradient layer technique, has become well established in the study of energy metabolism. The use of a commercially constructed gradient layer box within a calorimetry system designed to measure directly and indirectly the metabolic sequelae of thermal injury in rats, is described. Variations in the signal output were discovered. These were found to be dependent upon:

1. stability of the ambient temperature
2. stability of the gradient layer box water jacket temperature
3. position and size of the calibrating heat source.

Calibration with heat sources which simulate the heat emission from a rat, established that a measurement accuracy of ±2% can be achieved by controlling (a) and (b)     

The 16189 variant of mitochondrial DNA occurs more frequently in C282Y homozygotes with haemochromatosis than those without iron loading

Background:Patients with hereditary haemochromatosis (HH) are usually homozygous for the C282Y mutation in the HFE gene. They have variable expression of iron overload and present with a variety of complications, including liver disease, diabetes, arthropathy, fatigue, and cardiomyopathy. The mitochondrial 16189 variant is associated with diabetes, dilated cardiomyopathy, and low body fat at birth, and might contribute to genetic predisposition in further multifactorial disorders. The objective of this study was to determine the frequency of the 16189 variant in a range of patients with haemochromatosis, who had mutations in the HFE gene.

Methods:Blood DNA was analysed for the presence of the 16189 variant in British, French, and Australian C282Y homozygotes and controls, with known iron status, and in birth cohorts.

Results:The frequency of the mitochondrial 16189 variant was found to be elevated in individuals with haemochromatosis who were homozygous for the C282Y allele, compared with population controls and with C282Y homozygotes who were asymptomatic (42/292 (14.4%); 102/1186 (8.6%) (p = 0.003); and 2/64 (3.1%) (p = 0.023), respectively).

Conclusions:Iron loading in C282Y homozygotes with HH was exacerbated by the presence of the mitochondrial 16189 variant.

     

Microarray based comparative genomic hybridisation (array-CGH) detects submicroscopic chromosomal deletions and duplications in patients with learning disability/mental retardation and dysmorphic features

The underlying causes of learning disability and dysmorphic features in many patients remain unidentified despite extensive investigation. Routine karyotype analysis is not sensitive enough to detect subtle chromosome rearrangements (less than 5 Mb). The presence of subtle DNA copy number changes was investigated by array-CGH in 50 patients with learning disability and dysmorphism, employing a DNA microarray constructed from large insert clones spaced at approximately 1 Mb intervals across the genome. Twelve copy number abnormalities were identified in 12 patients (24% of the total): seven deletions (six apparently de novo and one inherited from a phenotypically normal parent) and five duplications (one de novo and four inherited from phenotypically normal parents). Altered segments ranged in size from those involving a single clone to regions as large as 14 Mb. No recurrent deletion or duplication was identified within this cohort of patients. On the basis of these results, we anticipate that array-CGH will become a routine method of genome-wide screening for imbalanced rearrangements in children with learning disability.     

Inhibition of colon carcinoma cell lung colony formation by a soluble form of E-selectin.

During metastasis, tumor cells adhere to vascular endothelia. E-selectin is an adhesive protein expressed by cytokine-activated endothelium that can support adhesion of colon cancer cells through the recognition of specific carbohydrate ligands. Using a series of colon carcinoma cell lines that displayed E-selectin adhesiveness and an increased metastatic capacity in cytokine-treated mice, we examined possible inhibition of cytokine-dependent experimental lung metastasis by a soluble form of E-selectin, the recombinant fusion protein E-selectin-immunoglobulin. We found that E-selectin-immunoglobulin bound to the surfaces of HT-29 colon carcinoma cells and blocked the formation of cytokine-inducible experimental lung metastases; control L-selectin-immunoglobulin also bound to HT-29 cells but had no effect on tumor cell lung colonization. E-selectin-immunoglobulin was found to interfere with E-selectin-dependent adhesion of HT-29 cells to activated vascular endothelium and to block the retention of these cells in the lung, a process that implies tumor cell adhesive interactions with the host vasculature. Our results demonstrate that E-selectin-immunoglobulin inhibits adhesion and formation of lung metastases by colon carcinoma cells and suggest that impairment of tumor cell-endothelium adhesion might represent a therapeutic approach to the metastatic diffusion of tumors.     

Oestrogen receptors in colorectal carcinoma.

The oestrogen receptor content of colorectal adenocarcinoma was investigated using an established ligand binding biochemical assay and two more recently introduced techniques using specific monoclonal antibodies (Abbott ER-EIA and ER-ICA assay kits). Twenty nine tumours were investigated by the ligand binding assay. Only one (3.4%) tumour gave a weakly positive result (11 fmol/mg cytosol protein); the rest were all negative. Where sufficient tissue was available, the receptors were also determined by a quantitative immunoassay in 18 patients and an immunohistochemical method in 13 patients. The results were similarly all negative. It is concluded that most colorectal carcinomas, irrespective of sex, are oestrogen receptor negative, and it is thus unlikely that hormonal manipulation would have an influence on the course of the disease.     

Enhancement of cALL immunogenicity by co-culture with a CD154 expressing 293 cell line

Pre-B cell acute lymphoblastic leukaemia (cALL) commonly occurs in young patients and although successful conventional therapies are available (such as cytotoxic drugs and bone marrow transplantation) for a proportion of patients (approximately 30%) these are ultimately unsuccessful. Recurrence of disease is a result of the failure of the immune system to recognize these abnormal cells and down-regulation of crucial molecules required for cognate CD4(+) T cell recognition has been postulated as a means of immune escape. In this study we show that an embryonic kidney cell line (293 cells) transfected with CD154 (40 L.1) are capable of not only maintaining the viability of primary ALL cells in culture but can also up-regulate the expression of a number of crucial molecules involved in antigen recognition. We show that 40 L.1 cell stimulation of primary ALL cell cultures can not only enhance the allogeneic and autologous MLR response to such cells but will also induce CTL effectors which are capable of lysing wild-type autologous ALL cells. It is therefore conceivable that such an approach could be used to generate an active anti-tumour response in patients, following conventional therapy, reducing the incidence of recurrence.     

Comparison of indirect hemagglutination and rapid plate agglutination tests with counterimmunoelectrophoresis for typing Pasteurella haemolytica.

A rapid, simple, and accurate counterimmunoelectrophoresis (CIE) technique was developed and compared with the indirect hemagglutination and rapid plate agglutination techniques for serotyping cultures of Pasteurella haemolytica. The CIE test had 100% correlation with the conventional indirect hemagglutination test and, after serum absorption, correctly identified cultures representing the 12 established serotypes and 49 field isolates of P. haemolytica with reasonable rapidity. Cross-reactions were observed in the CIE and rapid plate agglutination tests but not in the indirect hemagglutination test with antisera prepared from the 12 established serotypes. These cross-reactions were eliminated from the CIE test but not from the rapid plate agglutination test by absorption of antisera with cells which possessed the cross-reacting antigens. Avian isolates of P. haemolytica did not type with antisera to the 12 established serotypes by any of the methods. Both homologous and heterologous reactions were observed with these strains in the rapid plate agglutination and CIE tests with antisera prepared from six selected cultures. These results support the previous finding that the taxonomic relationship of these avian strains to P. haemolytica is questionable.