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1.
Summary The role of mast cells in active and passive anaphylactic shock was examined using the WBB6F1 mouse, a genetically mast cell-deficient strain. Lethal anaphylactic shock occurred at high incidence rates in mice actively sensitized to bovine serum albumin (BSA). The reaction was specific to BSA since the shock could not be elicited by human or guinea pig serum albumin in these animals. Lethal shock could be prevented by CV-3988 but not by cyproheptadine, which suggests that the shock is mediated by PAF but not by histamine and serotonin. Similarly, lethal shock was provoked by homologous antigens in mice which had been passively sensitized with allogeneic anti-benzylpenicilloyl (BPO) IgG1 monoclonal antibody or with allogeneic or xenogeneic anti-BSA antiserum, but not in those sensitized with allogeneic anti-BPO IgE monoclonal antibody. These findings suggest that mast cells are not necessarily required for anaphylactic shock in the mouse.  相似文献   

2.
Non-adherent bone marrow-derived cells (NA-BMCs) are a mixed cell population that can give rise to multiple mesenchymal phenotypes and that facilitates hematopoietic recovery. We characterized NA-BMCs by flow cytometry, fibroblast colony-forming units (CFU-f), real-time PCR, and in in vivo experiments. In comparison to adherent cells, NA-BMCs expressed high levels of CD11b+ and CD90+ within the CD45+ cell fraction. CFU-f were significantly declining over the cultivation period, but NA-BMCs were still able to form CFU-f after 5 days. Gene expression analysis of allogeneic NA-BMCs compared to bone marrow (BM) indicates that NA-BMCs contain stromal, mesenchymal, endothelial cells and monocytes, but less osteoid, lymphoid, and erythroid cells, and hematopoietic stem cells. Histopathological data and analysis of weight showed an excellent recovery and organ repair of lethally irradiated mice after NA-BMC transplantation with a normal composition of the BM.  相似文献   

3.
Résumé Après injection de ferritine de cheval, des souris C2H axéniques développèrent des anticorps circulants ainsi que des immunoglobulines sans affinité pour l'antigène dans chacune des classes: IgA, IgM, IgG1, et IgG2. Après immunisation orale, la réponse spécifique fut exclusivement du type IgA, et la réponse non-spécifique principalement du type IgG2 et IgA.

Belgian American Educational Foundation Fellow.

Staff Member of the Biology Division of Euratom, Euratom Publication No. 486.

The Rega Institute for Medical Research, Louvain.  相似文献   

4.
Summary Somatic cell hybrids between Sp2/O-Ag14 mouse myeloma cells and lymphocytes derived from BALB/c mice hyperimmunized with sheep red blood cells (SRBC) were produced. One hybrid producing IgG1 antibody to SRBC was selected, cloned twice and subsequently transferred to BALB/c mice. After a number of transfers it was found that the antibody titer in ascitec fluid gradually decreased. Cytogenetic analysis revealed gradual chromosome loss in the hybrid clone, which produced progressively less antibody.  相似文献   

5.
Summary One or two injections two weeks apart of protein-conjugated penicillin G, cephalothin or cefmetazole emulsified with Freund's complete adjuvant were quite effective in producing anti-antibiotic antibodies of the IgE as well as of the IgG1 class in mice. Long-lasting and boostable production of both antibody classes was also obtained against unconjugated cephalothin or cefmetazole, though the positivity depended on the mouse strain.  相似文献   

6.
7.
IgM antibodies directed against neuronal gangliosides GM1 , GM2 , GD1a , GD1b and GT1b occur in normal individuals and their level significantly decreases with age. Patients with lower motor neuron disease (LMND) produce high levels of these autoantibodies. AntiGM1 IgM is selectively augmented. In these patients, the CD5+ (B1) and CD5− (B2) subsets of B cells are not distinct entities but range from those without detectable CD5 marker to those with high CD5+ expression. B1 B cells were sorted to homogeneity, but B2 B cell cannot be isolated to homogeneity because of the presence of B1 cells with low CD5 expression. In short term cultures both the subsets produced IgM antibodies, but the antibodies reacted better with desialylated GM1 than with GM1 . Cycloheximide (Cx) (0.35 mM) largely blocked IgM synthesis of the B1 B cells but inhibition of the B2 B cells was incomplete, possibly due to shedding of cytophilic antibodies as well as to the presence of B1 phenotype with loss of CD5 expression. CD5+ B cells may be involved in the production of antiglycolipid IgM. Received 9 June 1997; received after revision 21 July 1997; accepted 28 July 1997  相似文献   

8.
Summary Guinea-pig respiratory and serum antibody responses were enhanced following exposure to aerosols of bovine IgG2 dissolved in solutions of sodium dodecylbenzene sulphate (SDBS). Enhanced response was seen in both primary and secondary immunization. Cell-mediated immune response (indirect macrophage migration influencing test) was not altered by SDBS. Results are discussed with a view to the possible utility of SDBS as adjuvant for prophylactic immunization.Acknowledgment. This research was supported by a grant from the Ontario Ministry of Health. The technical assistance of Ms Judy Little is gratefully acknowledged.  相似文献   

9.
Among the heterogeneous population of circulating hematopoietic and endothelial progenitors, we identified a subpopulation of CD133+ cells displaying myogenic properties. Unexpectedly, we observed the expression of the B-cell marker CD20 in blood-derived CD133+ stem cells. The CD20 antigen plays a role in the modulation of intracellular calcium homeostasis through signaling pathways activation. Several observations suggest that an increase in intracellular calcium concentration ([Ca2+]i) could be involved in the etiology of the Duchenne muscular dystrophy (DMD). Here, we show that a CD20-related signaling pathway able to induce an increase in [Ca2+]i is differently activated after brain derived neurotrophic factor (BDNF) stimulation of normal and dystrophic blood-derived CD133+ stem cells, supporting the assumption of a “CD20-related calcium impairment-affecting dystrophic cells. Presented findings represent the starting point toward the expansion of knowledge on pathways involved in the pathology of DMD and in the behavior of dystrophic blood-derived CD133+ stem cells. Received 15 October 2008; received after revision 27 November 2008; accepted 05 December 2008  相似文献   

10.
Summary Propane sultone (PS) injected i.p. 24 or more hours before Friend leukemia virus increased the incidence of lymphoma in SJL/J mice and at a higher dose increased the incidence of erythroleukemia in B10SJF1 mice. PS at the same time also decreased hematopoietic stem cell clonogenicity.  相似文献   

11.
The isolation of human epidermal stem cells is critical for their clinical applications. In the present study, we isolated three populations of epidermal keratinocytes according to their ability to adhere to collagen type IV: i.e., rapidly adhering (RA), slowly adhering (SA), and non-adhering (NA) cells. The aim of this study was to characterize RA cells and to investigate the possibility of using these cells for epidermis reconstruction. To identify RA cells, flow cytometric analysis was performed using anti-6 integrin and anti-CD71 antibodies. RA cells express high levels of 6 integrin and low levels of CD71, which are considered as markers of an epidermal stem cell nature. Furthermore, electron microscopy showed that RA cells are small and have a high nuclear to cytoplasmic ratio, whereas SA and NA cells have well-developed cellular organelles and abundant tonofilaments. Western blot analysis showed that RA cells are slow cycling and express p63, a putative epidermal stem cell marker, whereas SA and NA cells express c-Myc, which is known to regulate stem cell fate. To compare epidermal regenerative abilities, skin equivalents (SEs) were made using RA, SA, and NA cells. The epidermis constructed from RA cells was well formed compared to those formed from SA or NA cells. In addition, only SEs with RA cells expressed 6 integrin and 1 integrin at the basal layer. These results indicate that RA cells represent epidermal stem cells and are predominately comprised of stem cells. Therefore, the isolation of RA cells using a simple technique offers a potential route to their clinical application, because they are easily isolated and provide a high yield of epidermal stem cells.Received 2 July 2004; received after revision 20 August 2004; accepted 10 September 2004  相似文献   

12.
Using the lymphocyte reaction (MLR) as an in vitro model of allogeneic response we have demonstrated that red blood cells (RBC), when phagocytosed by monocytes present in the reaction, induce almost complete suppression of the MLR. A similar effect is achieved by the RBC lysate or purified hemoglobin. These data strongly suggest that the better graft tolerance apparently induced by blood transfusion given to the recipient at the time of transplantation may result from a non specific immunodepressive process induced by the injected erythrocytes, and mediated by the monocyte.  相似文献   

13.
Summary Antibody against aflatoxin M1 was obtained after immunization of rabbits with bovine serum albumin-afla M1 oxime conjugate. The antibody has greatest binding efficiency for afla M1, and was less efficient for afla B1. Cross-reaction of antibody with aflatoxin Q1, aflatoxicol, and aflatoxin B2a was weak. Aflatoxin B2, G1, and G2 and afla B1-guanine adduct showed almost no cross-reaction with the antibody. The sensitivity of the binding assay for aflatoxin M1 detection is in the range of 1–10 ng per assay. Detailed methods for the preparation of the conjugate, production of immune serum, and methods for antibody determination are described.Supported by the College of Agricultural and Life Sciences, North Central Regional project NC-129, the University of Wisconsin-Madison, and by Public Health Service research grant number CA 15064 from the National Cancer Institute, NIH.The authors wish to thank Dr R.C. Garner for providing aflatoxin-B-guanine adduct, and Dr Dennis H. Hseih for providing aflatoxicol and aflatoxin Q1.  相似文献   

14.
Mast cells play pivotal roles in allergic and inflammatory processes via distinct activation pathways. Mucosal and serosal mast cells are activated by the IgE/FcɛRI pathway, while only serosal mast cells are activated by basic secretagogues. We show that CD47 receptors are expressed on rat peritoneal mast cells. 4N1K, a peptide agonist of CD47, rapidly caused exocytosis. Such exocytosis required increased intracellular calcium and was inhibited by pertussis toxin and an antibody against the βγ dimer of a Gi protein. Cooperation with integrins and glycosylphosphatidylinositol-anchored proteins was necessary, since anti-integrin antibodies and pretreatment with phosphatidylinositol-phospholipase C reduced exocytosis. Depletion of membrane cholesterol inhibited exocytosis and decreased CD47 in lipid rafts, consistent with a CD47/integrin/Gi protein complex being located in rafts. An anti-CD47 antibody inhibited exocytosis induced by 4N1K and by mastoparan and spermine, suggesting that basic secretagogues might target CD47. We propose that 4N1K-stimulated mast cell exocytosis involves a CD47/integrin/Gi protein complex. Received 8 December 2008; received after revision 12 January 2009; accepted 29 January 2009  相似文献   

15.
Zusammenfassung AusMaackia amurensis Rupr. et Maxim. var.Buergeri (Maxim.) C. K. Schneid wurde ausser dem bekannten Sophorol ein Phenol C16H12O5 isoliert. Auf Grund spektroskopischer Untersuchungen und dem Vergleich mit einem synthetisch hergestellten Derivat (III;R=CH3) wird dem Maackiain die Struktur (I;R=H) eines Chromanocumarans zugeschrieben.

Paper IV. Paper III in this series seeH. Suginome, Tetrahedron Letters No. 19, 16 (1960).

Read before the 14th Annual Meeting of the Chemical Society of Japan, Tokyo (April 1961).  相似文献   

16.
The effect of incubation medium osmolality on the respiratory burst of human neutrophils was studied using luminol-dependent chemiluminescence (CL) as an indicator of burst activity. Neutrophils were stimulated with N-formyl-Met-Leu-Phe (FMLP), phorbol-12-myristate-13-acetate (PMA), the calcium ionophore A23187, thermoaggregated IgG (IgGn), and opsonized zymosan (OZ). It was shown that increasing the osmolality of the incubation medium from 320 up to 420 mosM decreased the A231870 and OZ-induced CL responses by 90%. Under the same conditions PMA-, FMLP- and IgGn-induced CL responses were decreased by 40–60%. A decrease of osmolality to 200 mosM resulted in a 2–3 fold decrease of the A23187-, PMA- and FMLP-induced CL and in a 60–80% increase of OZ- and IgGn-induced CL. It is suggested that osmolality-mediated alteration of cell volume is an important mechanism for regulating neutrophil activity.  相似文献   

17.
Roles for interleukin-2(IL-2) and IL-4 in the generation of murine allocytotoxine T lymphocytes (allo-CTL) in the primary and secondary responses were studied in vitro. The generation of allo-CTL in the primary response was inhibited by anti-IL-2 monoclonal antibody (mAb), but was not inhibited by anti-IL-4 mAb. On the other hand, the generation of allo-CTL in the secondary response was partially inhibited by either anti-IL-2 or anti-IL-4 mAb, and it was almost completely inhibited by the combination of two mAbs. CD8+ cell-depleted splenocytes produced IL-2, but not IL-4, in response to alloantigens in the primary response, and these cells produced both IL-2 and IL-4 in the secondary response. Both exogenous IL-2 and IL-4 induced functionally active allo-CTL in the primary response from CD4+ cell-depleted splenocytes when these cells were stimulated with T cell-depleted allogeneic cells. These results suggest that the allo-CTL induction in the primary response is IL:-2-dependent and secondary allo-CTL induction is both IL-2 and IL-4-dependent, because unprimed CD4+ T cells produce IL-2, but not IL-4, whereas primed cells produce both IL-2 and IL-4 in response to alloantigens.  相似文献   

18.
Summary Transplantation of virus and chemically induced leukemias from C3H/He-mgxAKR/F1 hybrid mice into C3H/He-mg males induced leukemias in the latter, which was followed by a spontaneous regression of the disease within a few days. The regression of leukemia could easily be followed by measuring the changes in the pyruvate kinase activity of para-aortic lymph node cells.  相似文献   

19.
Our previous study revealed that passive cutaneous anaphylaxis (PCA) can be produced in congenitally mast cell-deficient WBB6F1-W/Wv (abbreviated as W/Wv) mice on sensitization with undiluted or slightly diluted allogeneic and xenogeneic antisera but not on sensitization with allogeneic monoclonal immunoglobulin (Ig)E and IgG1 antibodies regardless of the antibody concentration [1]. In view of these findings, the present study was conducted to characterize PCA in this strain from its drug susceptibilities using mast cell-bearing WBB6F1-+/+ (abbreviated as +/+) and B6D2F1 mice as references. PCA in W/Wv mice mediated by a low dilution (1  4) of hyperimmune serum to bovine serum albumin of the B6D2F1 mouse origin was markedly suppressed by CV-6209, an antagonist of platelet-activating factor (PAF), but not by antihistamines such as cyproheptadine and oxatomide. In contrast, PCA in +/+ and B6D2F1 mice mediated by a high dilution (1  128) of the anti-serum (virtually by IgG1 antibody) was nearly completely suppressed by antihistamines but not by CV-6209. A remarkable difference between PCA in W/Wv and reference mice was also observed in the susceptibility to monoclonal anti mouse granulocyte (Gr-1) antibody PCA in W/Wv mice was potently suppressed by the 1- to 3-day pretreatment with this antibody but that in references was not at all. Putting these present results together with the previous finding that anti-granulocyte antibody greatly reduces circulatory Gr-1+ leukocytes, 1 to 3 days after the treatment [2], it is highly probable that PCA in W/Wv mice mediated by some antibody isotypes other than IgE and IgG1 is produced by PAF mainly released from Gr-1+ cells, while IgG1 antibody-mediated PCA in mast cell-bearing reference mice is evoked by histamine derived from mast cells. PCA homologous to that in W/Wv mice could also be produced in the reference mice on sensitization with undiluted or slightly diluted antiserum, when generalized blueing due to excess IgG1 antibody was removed by the oxatomide treatment be fore the antigen challenge. Received 10 December 1997; received after revision 2 February 1998; accepted 23 February 1998  相似文献   

20.
Glycerol, injected into a site between the femoral vessels of the rat, induced neovascularization, both from the preexisting microcirculation and from the side of the femoral vein facing the artery-vein interstitium where the glycerol was administered. The use of glycerol together with a known angiogenic substance (PGE2) did not modify the neocapillary density (NCD) obtained with glycerol alone. In contrast, the lower level of NCD achieved with an acylglycerol (triacetylglycerol) was increased when the latter was associated with PGE2. Values reached were similar to, but never higher than, those for glycerol alone, or combined with PGE2. The results suggest that glycerol and some substances containing glycerol, amongst which 1-butyrylglycerol has been previously considered1, may stimulate angiogenesis by a direct or indirect mechanism of action.  相似文献   

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