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.     

Detection of human papillomavirus type 16 DNA in cervical swabs and formalin-fixed, paraffin-embedded squamous cell carcinomas of non-genital tissues using a synthetic oligodeoxynucleotide probe

The potential of using a chemically synthesized oligodeoxynucleotide as a diagnostic probe to detect human papillomavirus type 16 (HPV-16) in genital infections was evaluated by comparing it with a cloned full-length HPV-16 probe in dot-blot DNA hybridizations. An oligonucleotide sequence, 20 bases in length from the E6 region of HPV-16 (E6 oligo) and different from the DNA sequences of HPV types 6, 11 and 18 by at least 2 base pairs, was chosen for chemical synthesis. The oligoprobe, which was 5'-end labelled with [32P]dATP, was found to be specific, but approximately ten times less sensitive than the full-length radiolabelled probe of HPV-16, in dot-blot hybridizations with the DNA of HPV-6, -11, -16 and -18, HPV positive and negative cell-lines. From 36 cervical or vulval scrapes two samples were found positive with both cloned HPV-16 and oligoprobe hybridization. Of 21 samples of formalin-fixed, paraffin-embedded squamous cell carcinomas originating from anus, oesophagus, penis, colon, breast and skin only 4 anal squamous cell carcinomas were positives when hybridized with cloned HPV-16 DNA or with the oligoprobe. This study confirms that HPV-16, which is frequently associated with squamous cell carcinoma of the cervix is also strongly associated with squamous cell carcinoma of the anus.     

Blood-free selective medium for isolation of Campylobacter jejuni from feces

A blood-free selective agar is described which contains charcoal, ferrous sulfate, sodium pyruvate, casein hydrolysates, cefazolin, and sodium deoxycholate (CCD agar). CCD agar was compared with Preston medium for isolation of Campylobacter jejuni from human feces, and isolation rates were similar on both media, but CCD agar was less selective. Temperature studies at 37 and 42 degrees C confirmed that incubation of direct plates at 42 degrees C for 48 h was necessary for maximum isolation of C. jejuni.     

Autoimmunity and glomerulonephritis in mice with targeted deletion of the serum amyloid P component gene: SAP deficiency or strain combination?

Human serum amyloid P component (SAP) binds avidly to DNA, chromatin and apoptotic cells in vitro and in vivo. 129/Sv x C57BL/6 mice with targeted deletion of the SAP gene spontaneously develop antinuclear autoantibodies and immune complex glomerulonephritis. SAP-deficient animals, created by backcrossing the 129/Sv SAP gene deletion into pure line C57BL/6 mice and studied here for the first time, also spontaneously developed broad spectrum antinuclear autoimmunity and proliferative immune complex glomerulonephritis but without proteinuria, renal failure, or increased morbidity or mortality. Mice hemizygous for the SAP gene deletion had an intermediate autoimmune phenotype. Injected apoptotic cells and isolated chromatin were more immunogenic in SAP(-/-) mice than in wild-type mice. In contrast, SAP-deficient pure line 129/Sv mice did not produce significant autoantibodies either spontaneously or when immunized with extrinsic chromatin or apoptotic cells, indicating that loss of tolerance is markedly strain dependent. However, SAP deficiency in C57BL/6 mice only marginally affected plasma clearance of exogenous chromatin and had no effect on distribution of exogenous nucleosomes between the liver and kidneys, which were the only tissue sites of catabolism. Furthermore, transgenic expression of human SAP in the C57BL/6 SAP knockout mice did not abrogate the autoimmune phenotype. This may reflect the different binding affinities of mouse and human SAP for nuclear autoantigens and/or the heterologous nature of transgenic human SAP in the mouse. Alternatively, the autoimmunity may be independent of SAP deficiency and caused by expression of 129/Sv chromosome 1 genes in the C57BL/6 background.     

Hepatitis C virus seroconversion rate in established blood donors

The results of hepatitis C virus (HCV) antibody test of 237, 813 blood donations collected from 143, 815 donors by the West Midlands Blood Transfusion Centre in 1993 were analyzed retrospectively in order to determine the seroconversion rate among established previously anti-HCV negative donors. Three hundred sixteen (0.22%; 1 in 455) donors were positive by the enzyme linked immunosorbent assay (ELISA) screening test and 34 (0.024%; 1 in 4, 230) donors were positive by ELISA and the Recombinant Immuno Blot Assay (RIBA). Three donors previously negative for HCV antibody reacted positively by both tests. The annual seroconversion rate was calculated as one in 35, 937 donors. This figure argues against limitation of HCV antibody screening to new blood donors. A further 45 donors negative on previous screening reacted positively by ELISA and were indeterminate by RIBA. Unexpectedly, lapsed blood donors first tested for HCV antibody in 1993 had high positive reaction rates by ELSA and RIBA, which was significantly (P < 0.001) higher than those of new donors. RIBA-positive reaction rate among ELISA-positive donors was significantly higher amongst males than females (P < 0.0011. © 1995 Wiley-Liss, Inc.     

The clinical comparison of Oxoid Signal with Bactec blood culture systems for the detection of streptococcal and anaerobic bacteraemias.

Blood cultures were taken from 47 patients 1-2 min after dental extraction. These samples were tested by the radiometric Bactec 460 and Oxoid Signal systems for the detection of streptococcal and anaerobic bacteraemias. Streptococci were isolated from 19 (40%) patients and anaerobes from 15 (32%). In this study the Oxoid Signal system was significantly better for isolating oral anaerobes than the Bactec system; five isolates were obtained with the Bactec system and 14 with the Signal system. There was no significant difference in the isolation of streptococci between these two systems (Bactec 14, Oxoid Signal 10). The contamination rate was 4.1% for Bactec and 7.5% for the Oxoid Signal system.     

The inferior alveolar artery in its bony course

Based on the dissection of 30 hemi-mandibles, the authors report a study of the inferior alveolar artery in its intraosseous course. On morphologic considerations they propose a classification of the collaterals into two groups: the principal collaterals destined for the teeth and the bony alveolar tissue and the secondary collaterals destined for the sheath and the nerve as well as the bony tissue around the canal. Loss of the teeth and absorption of the alveolar bone modify the caliber of the inferior alveolar arterial axis, the distribution of its collaterals and possibly its mode of termination. These facts suggest a consideration of the vascularization of the mandible in terms of four sectors. They arrive at practical conclusions that may be drawn from this study in stomatology.     

Classical and alternative pathway complement activation are not required for reactive systemic AA amyloid deposition in mice

During induction of reactive systemic amyloid A protein (AA) amyloidosis in mice, either by chronic inflammation or by severe acute inflammation following injection of amyloid enhancing factor, the earliest deposits form in a perifollicular distribution in the spleen. Because the splenic follicular localization of immune complexes and of the scrapie agent are both complement dependent in mice, we investigated the possible complement dependence of AA amyloid deposition. In preliminary experiments, substantial depletion of circulating C3 by cobra venom factor had little effect on experimental amyloid deposition. More importantly, mice with targeted deletion of the genes for C1q or for both factor B and C2, and therefore unable to sustain activation, respectively, of either the classical complement pathway or both the classical and alternative pathways, showed amyloid deposition similar to wild type controls. Complement activation by either the classical or alternative pathways is thus not apparently necessary for the experimental induction of systemic AA amyloid in mice.