ISSN:0004-945X    

DOI:10.1038/icb.1995.31

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryA feature common to many blood cell cancers is the uncoupling of normal proliferative and differentiative events, both of which are intimately linked in the cell's developmental programme. In some cancers, further differentiative events have been associated with oncogenic progression and, in other cancers, terminal differentiation of cells has been shown to result in reversal of malignancy and death of the cancer cell. Clearly the development of cancer is not the result of a single oncogenic event, but rather a myriad of events which appear to proceed in concert in a step‐wise fashion and which are likely to be influenced by the cellular environment.Here we review some of the major genetic changes which occur in leukaemogenesis and discuss the possible role of differentiative events in the development of leukaemia.

ISSN:0004-945X    

DOI:10.1038/icb.1995.32

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryAntigen specific B cells (ASC) that circulate after oral immunization with the typhoid vaccine Ty2 1a display cell surface determinants which are potentially involved in B cell differentiation and homing to mucosal sites. These ASC were isolated from peripheral blood after oral Ty21a, and dual labelled for binding of typhoid antigen and expression of various cell surface determinants: a4 integrin (CD49d), CD45RO, CD45RA, L‐selectin, CD44 and CDl la. Of particular interest was the finding of CD45RO expression on ASC. A comparison of cell surface determinants on typhoid‐specific cells was also made following binding to high endotheliai venules on peripheral and mesenteric lymph nodes, and venules in the lamina propria of the small intestine. Generally more typhoid ASC bound to mesenteric compared with peripheral lymph node. More ASC expressing CD45RO and a4 integrin (CD49d) were bound to mesenteric lymph node and small intestine than to peripheral lymph node. When expressed as a fraction of total ASC, the difference was statistically significant only for CD45RO binding to small intestine versus peripheral lymph node. No differences in expression of other homing markers on bound ASC were seen.

ISSN:0004-945X    

DOI:10.1038/icb.1995.33

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryDendritic cells (DC) are antigen‐presenting cells characteristic in their rarity and potent ability to stimulate resting T cells. We established several cell lines from purified mouse spleen DC and Langerhans' cells (LC) by infecting them with recombinant SV40ori−adenovirus. Using this method, cells from these fractions are efficiently transformed at a frequency as high as 5 × 10−6. Some established lines have dendritic morphology, express surface markers specific for DC (defined by mAb 33D1 and NLDC145) and weak substrate adherence. Interestingly, these lines simultaneously express B cell markers (B220 and Ly‐1) and/or macrophage markers (Mac‐l and F4/80). Among the lines, OT6.2 and OT8.3.1 have retained stimulating activity in mixed lymphocyte reactions (MLR) which is attributable to the primary T cell stimulating activity of native DC However, these lines also present soluble antigens to T cell clones, a secondary T cell stimulating activity, characteristic of B cells and macrophages. Although transformation has perturbed the functional discreteness of the DC cell lineage. DC‐specific properties are partially preserved in the cell lines. These cell lines may provide useful experimental systems for the elucidation of molecular mechanisms involved in the MLR and the differentiation of DC.

ISSN:0004-945X    

DOI:10.1038/icb.1995.34

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryMast cells were purified by discontinuous density gradient centrifugation to greater than 90% and subsequently exposed to lactic acid in order to dissociate endogenous IgE. Unfortunately no removal of this IgE was achieved, despite previous reports of lactic acid exposure dissociating IgE from human basophils. Only a minimal level of endogenous IgE was found on the surface of mast cells, however, which allowed investigations of IgE binding to proceed without the initial removal of this endogenous IgE. Conditions for binding of normal rat IgE and myeloma IgE were established while efforts to bind human IgE to purified rat mast cells were unsuccessful. Our results suggest that while purified rat mast cells have the potential to play an important role in the study of the IgE requirement of various stimuli including histamine‐releasing factor, this role is limited at present.

ISSN:0004-945X    

DOI:10.1038/icb.1995.35

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryIn the present study the effect of tumour growth with respect to two tumour systems (Dalton's lymphoma [DL] and P815) on thein vitro, colony‐forming ability (CFA) and proliferation of the bone marrow cells (BMC) of C3H/He mice was investigated. The P815‐bearing mice showed an enhanced bone marrow colony forming abilityin vitro, in response to L929 conditioned medium (L929 CM) used as a source of CSF. On the other hand, DL‐bearing mice did not have any significant alteration in this process compared to normal mice.In vivo, administration of cisplatin resulted in a significant rise in the CFA of normal as well as DL‐ or P815‐bearing mice. The tumour‐conditioned medium (TCM) and ascitic fluid (AF) of P815 but not of DL, was found to support thein vitrocolony formation of BMC obtained from cisplatin‐treated or untreated mice. The number of CFU‐granulocyte‐macrophage was predominantly high in the cultures of BMC incubated with TCM or AF of P815. The TCM and AF of P815 also enhanced thein vitroproliferation of BMC obtained from cisplatin‐treated or untreated mice.In vivo, administration of cisplatin in normal mice resulted in enhanced numbers of peritoneal exudate macrophages (PEM) and PBL. Similarly, the number of PEM and PBL was augmented in both the P815‐ and DL‐bearing mice. However, cisplatin administration in the tumour‐bearing mice decreased the count of PEM, while the number of leucocytes remain unaffected. This study indicates that the cancer chemotherapeutic drug cisplatin can influence the differentiation of the bone marrow progenitor cells in response to tumour growthin situ.

ISSN:0004-945X    

DOI:10.1038/icb.1995.36

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryIn the ‘sunburn’ response in skin, dermal blood vessels are activated and traffic of dendritic Langerhans' cells altered. While these changes have been attributed to the cytokine TNF‐α, the source of this acutely released TNF has not been identified. This report demonstrates that the ‘sunburn’ response, bothin vivoandin vitro, is accompanied by rapid degranulation of cutaneous mast cells, with consequential release of intracellular stores of TNF. Epidermal keratinocytes were only minor contributors to local TNF production. Expression of the TNF‐inducible CD62E (E‐selectin/ELAM‐1) and CD54 adhesion molecules on cutaneous endothelium occurred 2 h following mast cell degranulation, and this event was sensitive to blockade of mast cells with disodium cromoglycate. These results indicate that TNF release in skin in the acute sunburn response can largely be attributed to mast cells.

ISSN:0004-945X    

DOI:10.1038/icb.1995.37

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryHuman neutrophils are able to killin vitrocolorectal carcinoma cell line SW11‐16 coated with mAb 17‐1A, but they are not cytotoxic towards a non‐immunized tumour target. Neutrophil exposure to the inflammatory cytokine, IL‐8, produces a significant increase in antibody‐dependent cellular cytotoxicity, which is related to IL‐8 concentration. Oxyradical production is one of the lytic mechanisms used by phagocytes, and IL‐8 is shown to activate this function, which does not occur if neutrophils are pretreated with the protein kinase C inhibitor, staurosporine, but is increased by R59022, a dyacylglycerol kinase inhibitor. The IL‐8 effect is mediated by protein kinase C, which is potentiated by the calcium flux induced by the interaction between antibody coating tumour target and FcγRIII on effector cells, as previously demonstrated. Data suggest a possible new role for IL‐8 in tumour surveillance.

ISSN:0004-945X    

DOI:10.1038/icb.1995.38

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryThe biological effect of visible light of low energy density was investigated in this study. The effects of diffuse (DL) and linearly polarized (LPL) light were compared on modelsin vitroandin vivo.Experimentsin vitrowere performed on human lymphocytes to study their blast‐transformation and rosette‐formation abilities. Both DL and LPL increased the number of blast‐transformed cells even in a lymphocyte culture without PHA, and reduced rosette‐formation of T lymphocytes. LPL had a more pronounced effect.In vivoexposure to DL and LPL of the spleens of tumour‐bearing mice caused the appearance of factor(s) in their serum, inhibiting the incorporationin vitroof [3H]‐thymidine into the tumour cells obtained from non‐exposed animals. In the other series of experiments serum samples were taken from tumorous animals after the exposure of their spleens to LPL. Following the daily administration of these sera to another group of non‐exposed tumorous mice a decreasing tendency of the mitotic kinetics of ascites tumour was observed.The application of visible (preferably linearly polarized) light for the stimulation of human immune competent cells, and clinical trials with extracorporeal irradiation of blood for the promotion of natural defences of an immune‐repressed organism are suggested.

ISSN:0004-945X    

DOI:10.1038/icb.1995.39

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY

摘要:

SummaryThe lymphocyte subset expressing the γδ T cell receptor is increased in several infectious diseases including HIV infection. In this study the expression on γδ lymphoctyes of the T cell activation markers CD25, HLA‐DR and CD38, as well as the two isoforms of CD45, namely CD45RA and CD45RO, was determined in the peripheral blood of 56 HIV‐infected intravenous drug users and 34 HIV‐seronegative blood donors by two‐colour flow cytometry. The percentage of γδ lymphocytes expressing HLA‐DR and CD38 was higher than those in HIV‐seronegative controls (P<0.001 andP<0.0001, respectively). Furthermore the HLA‐DR+γδ+lymphocytes correlated inversely with CD4+T lymphocyte absolute count (P<0.02 for both). The levels of γδ lymphocytes expressing CD25, CD45RA and CD45RO were similar to those in HIV‐seronegative controls. Activated γδ lymphocytes may play a role in the HIV disease process and could provide a useful marker for disease progression.

ISSN:0004-945X    

DOI:10.1038/icb.1995.40

出版商:Blackwell Publishing Ltd    

年代:2017

数据来源: WILEY