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1.
Immune cells transferred into nonirradiated animals of the same genotype face a barrier which severely affects their capacity to function in the host. We studied this phenomenon in allotype-congeneic animals. When anti-dextran immune cells of the responder strain (BALB/c-Igha) are injected into an allotype-congeneic host (BALB-Ighb) the grafted cells are suppressed to give an idiotype-positive response. This congeneic barrier of thymus-independent immune cells is lost in mice carrying an X-linked B cell defect: when idiotype-positive immune cells from responder (CBA/N X BALB/c)F1 mice are transplanted into congeneic nonresponder animals (CBA/N X BALB-Ighb)F1, female recipients are nonpermissive towards grafted cells whereas B cell-defective male littermates allow donor cells to develop an idiotype-positive anti-dextran response. These results show that the congeneic barrier towards dextran-immune cells is related to the maturation stage of B cells in the recipient. Since B cell-defective (CBA/N X BALB/c)F1 animals do not display an anti-idiotypic response in contrast to intact littermates and because CB16-KN mice are nonpermissive towards CB8-K lymphocytes, differing in VH genes only, we suggest that the "isogeneic barrier" depends on a mechanism recognizing VH structures.  相似文献   

2.
CBA/N mice have an X-linked immune defect in B lymphocyte function which leads to their inability to respond to several thymus-independent antigens. We report here that these mice and immunologically defective F1 male (CBA/N X DBA/2N) mice can respond to Brucella abortus and to 2,4,6-trinitrophenyl derivatives of Brucella abortus (TNP-BA). These responses can be obtained in vivo and in vitro and are thymus-independent by the criteria that (a) they can be transferred to irradiated recipients by bone marrow cells and anti-Thy-1.2 and complement-treated spleen cells; (b) that nu/nu BALB/c spleen cells respond to TNP-BA in vitro; and (c) that anti-Thy-1.2 and complement-treated (CBA/N X DBA/2N)F1 male spleen cells respond to TNP-BA in vitro. B. abortus and TNP-BA are poor polyclonal B cell activators (PBA) and poor B cell mitogens, unlike lipopolysaccharide which is both a powerful PBA and B cell mitogen. These results therefore indicate that mice with the CBA/N B cell defect can respond to some thymus-independent antigens, namely TNP-BA, and as shown previously, TNP-LPS, although not to other thymus-independent antigens. This, in turn, suggests that thymus-independent antigens may be subdivided on the basis of their ability or inability to stimulate responses by CBA/N B lymphocytes.  相似文献   

3.
Studies were initiated to determine whether an immune response to the Mls antigen of C3H mice could modify responses of CBA lymphocytes (H-2-compatible) to a foreign H-2 complex. CBA lymphocytes, partially tolerant to the C5H-determined Mls antigen, generated less effector cell activity against C57Bl cells (H-2-incompatible) Chan lymph node cells from normal CBA donors when infused into irradiated C.3H × C57Bl hosts. Effector cell activity was measured as the capacity of the cells in the irradiated spleens to inhibit CBA × C57Bl bone marrow proliferation. In contrast, immunization of CBA mice with C3H × C57Bl cells yielded lower antibody titers against C577Bl cells than immunization with CBA × C57Bl cells. Furthermore, preinjection of CBA mice with C3H × CBA cells strongly reduced the capacity of the animals to produce antibodies against C57Bl cells. Thus, these data support the conclusion that an immune response to a foreign Mls antigen may either enhance or suppress an immune response to H-2-incompatible cells.  相似文献   

4.
In order to determine the carrier nature of lipopolysaccharide from Brucella abortus (LPS-BA) in evoking humoral responses, normal and immunodeficient mice were immunized with trinitrophenyl (TNP)-conjugated LPS-BA (TNP-LPS-BA) and the responses were compared with those to known T-dependent and T-independent antigens. TNP-LPS-BA, like T-independent type 1 (TI-1) antigens such as TNP-BA and TNP-LPS from Escherichia coli (TNP-LPS-EC), generated anti-TNP responses in BALB/c, athymic BALB/c nu/nu, and CBA/N mice. In contrast, N-2,4-dinitrophenyl-beta-alanylglycylglycyl-substituted keyhole limpet hemocyanin, a typical T-dependent antigen, was not immunogenic in athymic mice, and TNP-Ficoll (T-independent type 2) was ineffective in eliciting humoral responses in CBA/N mice. These results indicate that LPS from B. abortus acts as a TI-1 carrier in generating antibody responses. In C3H/HeJ mice, TNP-LPS-BA generated higher-titer immunoglobulin G1 (IgG1), IgG2a, and IgG2b anti-TNP antibodies than TNP-LPS-EC. Compared with those from BALB/c mice, pure resting B cells isolated from C3H/HeJ mice exhibited a 30-fold lower proliferative response to LPS-EC, whereas the LPS-BA response was reduced to a lesser extent (5-fold). This suggests that the disparity observed in antibody titers was due to different abilities of LPS from B. abortus and E. coli to stimulate C3H/HeJ B cells. The ability of LPS from B. abortus to act as a carrier in generating humoral immune responses indicates that LPS-BA can be substituted for whole B. abortus organisms in vaccine development.  相似文献   

5.
Pseudomonas exotoxin A has been implicated as a possible virulence factor in Pseudomonas infections. This toxin has a direct cytotoxic effect on a number of cell types, including macrophages and their precursors, and therefore may affect other cells of the immune system. NFR/N(H-2q) (+/nu or nu/nu) mice were immunized with either T-dependent or T-independent antigens along with various doses of exotoxin A. The immune response was then assayed by a modification of the Jerne plaque assay. Exotoxin A induced a dose-dependent suppression of the in vitro and in vivo immune responses to T-dependent and T-independent antigens in immunocompetent +/nu mice. However, in NFR/N nu/nu mice, suppression of the immune response to the T-independent antigen trinitrophenylated-Ficoll was not observed. Instead, a marked enhancement of the response was observed at doses of 100 and 10 ng of exotoxin A. Removal of T-cells with anti-Thy 1.2 antiserum plus complement before antigen and exotoxin A stimulation in +/nu mice results in abrogation of the suppression. These data suggest that Pseudomonas exotoxin A exerts an effect on both B- and T-lymphocyte populations to modulate the immune response and that this activity may be one facet of the pathogenic effects of this toxin.  相似文献   

6.
There is a strong stimulation of the primary immune response when spleen cells of the CBA/H and CBA/J strains of mice are cocultured in the Mishell-Dutton system and stimulated with foreign erythrocytes or hapten-erythrocyte conjugates. This stimulation occurs regardless of carrier (sheep red blood cells) priming of one donor of the spleen cells. The enhancement of the primary immune response is most evident early in the course of the immune response. During mixed spleen cell culture, cells of the CBA/H strain can recognize and proliferate in response to CBA/J spleen cells, but not vice versa. When CBA/H spleen cells are cultured with irradiated CBA/J spleen cells, there is a strong stimulation of the immune response of the B cells of the CBA/H strain even though they are bystanders to the ensuing allogeneic response. Supernatants of 20-hour cultures of mixtures of CBA/H and CBA/J spleen cells restored the immune responsiveness of spleen cells from nu/nu mice. The generation of this B cell stimulatory activity is dependent on the presence of Θ-bearing cells of CBA/H origin during the 20-hour culture. These findings are consistent with the release of a B cell stimulatory activity from mixtures of spleen cells of mice which differ at a locus associated with a mixed lymphocyte response which is not linked to the H-2 gene complex (M locus).  相似文献   

7.
CBA/N mice harbour an X-linked B cell defect which is transmitted by CBA/N female mice to their hybrid male progeny. These mice mount normal responses to thymus-dependent (TD) and some thymus-independent (TI-1) antigens, while the response to TI-2 antigens is absent. Hapten-specific plaque-forming cell (PFC) responses to TD antigens can be blockaded by concomitant exposure of these mice to TI-2 antigens bearing the same hapten. This paper investigates in defective mice the blockade of their response to TNP3-LPS (trinitrophenylated lipopolysaccharide, a TI-1 antigen), imposed by DNP59-Ficoll (dinitrophenylated Ficoll, a TI-2 antigen). The effectiveness of the blocking agent, DNP59-Ficoll, differed in various inbred mouse strains: CBA/N X C3H/HeN F1 male greater than CBA/N female greater than CBA/N X C3H/HeN F1 female. The role of T cells in the observed hapten-specific blockade phenomenon was investigated using athymic CBA/N nude mice and a B cell tolerogen. Our findings indicate that T cell participation is not essential for the blockade of CBA/N PFC responses and they suggest that direct blockade of TI- and TD-responsive B cell populations is likely to occur.  相似文献   

8.
Plaque-forming cell (PFC) responses to 2,4,6-trinitrophenylated lipopolysaccharide (TNP-LPS) were studied in normal and immunodeficient mice. In vivo immunizations with TNP-LPS showed a 25--50% reduction in PFC responses in CBA/N mice and their (CBA/N X BALB/c)F1(NBF1) male hybrids with an X-linked immune defect of B lymphocyte differentiation. A detailed clonal analysis of the reduced responses to TNP-LPS revealed that CBA/N and NBF1 male mice with the X-linked genetic defect have fewer precursor B cells engaged in the response to TNP-LPS than the control mice. The reduction in precursor cell numbers affects selectively B cells secreting high avidity anti-TNP antibodies as determined by PFC inhibition studies.  相似文献   

9.
The humoral immune response of inbred mice to immunization with the glucuronoxylomannan (GXM) of Cryptococcus neoformans was investigated both serologically and in plaque-forming cells (PFCs). The T-helper-cell-independent quality of the GXM was demonstrated by using BALB/c nu/nu mice. Primary and secondary dose responses to three antigenic forms of GXM, (i) the native antigen, (ii) a GXM-bovine serum albumin protein conjugate, and (iii) a cryptococcal whole-cell vaccine, revealed a lack of isotype class switching and anamnestic responses. Both the levels of complement-fixing anti-GXM antibody in serum and the PFC responses in the athymic mice showed no significant differences from those in the wild-type controls. However, T cells are involved in the suppression of the primary response to GXM. When BALB/cBy mice were given rabbit anti-mouse thymocyte serum along with 0.5 microgram of GXM, both antibody levels in serum and PFC responses were significantly increased over those of control mice that received GXM and normal rabbit serum. In addition, T cells were also shown to enhance the primary immune response to GXM. BALB/cBy mice were given GXM and anti-mouse thymocyte serum on day 1. On day 2, the experimental group was given anti-mouse thymocyte serum and the control group was given saline. On day 5, comparison of the PFC responses and anti-GXM antibody titers of the two groups revealed a significant increase in the immune response of the control over the experimental group. The type 2 T-cell-independent quality of GXM was also demonstrated in CBA/cHN xid mice. These mice lack the Lyb+ subset of B cells and are unable to respond to type 2 T-independent antigens but respond normally to type 1 T-independent antigens. Type III pneumococcal polysaccharide, a type 2 T-independent antigen, was used as a negative control, and trinitrophenyl-lipopolysaccharide, a type 1 T-independent antigen, was used as a positive control. The CBA/cHN xid mice failed to respond to either type III pneumococcal polysaccharide or GXM but did not respond to immunization with trinitrophenyl-lipopolysaccharide. BALB/cBy mice responded normally to all three antigens.  相似文献   

10.
The tetrasaccharide repeating unit of the capsular polysaccharide of Klebsiella serotype 11, K11PS, comprises the following sequence: [----3)-beta-D-GlcpA-(1----3)-alpha-D-Galp-(1----3)-beta-D-Glcp-(1 ----] with a 4,6-O-(1-carboxyethylidene)-alpha-D-galactopyranosyl residue linked to O-4 of the glucuronic acid residue. Octasaccharide (OS) derived from K11PS by bacteriophage phi 11-associated glycanase, was coupled to bovine serum albumin and to keyhole limpet hemocyanin. The immunogenicity of various antigens after intraperitoneal immunization was studied by measuring the levels of circulating antibodies. Injection of BALB/c mice with K11PS resulted in induction of 2-mercaptoethanol-sensitive immunoglobulin M antibodies. The responses observed in BALB/c nu/nu mice and in male (CBA/N X C3H/HeN)F1 mice indicate that K11PS is a thymus-independent type 2 antigen. Immunization of BALB/c mice with either OS-bovine serum albumin or OS-keyhole limpet hemocyanin resulted in the induction of circulating 2-mercaptoethanol-resistant immunoglobulin G antibodies. Results in BALB/c nu/nu mice indicate that the OS-protein conjugates are thymus-dependent antigens. Since the OS-keyhole limpet hemocyanin conjugate induced antibodies in both (CBA/N X C3H/HeN)F1 females and males, we propose to refer to this kind of antigen as a thymus-dependent type 1 antigen, whereas OS-bovine serum albumin, which evoked immunoglobulins in (CBA/N X C3H/HeN)F1 females only, can be referred to as a thymus-dependent type 2 antigen.  相似文献   

11.
In a survey of 301 normocomplementemic inbred mice (belonging to nine different strains: BALB/cN nu/nu and nu/+, CBA/N, C57BL/KsJ, C57BR/cdJ, CBA/CaJ, BRVR, DW/+, and C57BL/6J) for natural resistance to Cryptococcus neoformans, cumulative survival values were found to range from 12 to 22 days. When the average organ weights of infected animals were compared with reference values obtained in uninfected mice of the same age and genetic lineage, the following changes were documented. In the CBA/N strain, the mean spleen and brain weights increased 313 and 13.5%, respectively, whereas the mean liver weight remained unchanged. In the CBA/Ca strain, cerebral cryptococcosis was the dominant clinical feature, and a 54% increase in mean brain weight was recorded at the time of death. The averaged liver weight was drastically lower, whereas spleen weight values evinced a biphasic pattern of transient splenomegaly followed by involution. At the median time of death, CBA/N mice had significantly more cryptococci in the liver and spleen than corresponding CBA/Ca mice. In the (CBA/N X CBA/Ca)F1 mice, susceptibility to C. neoformans segregated according to the sex-linked inheritance of the X-linked immunodeficiency (xid) gene. It is concluded that (i) susceptibility to cryptococcosis is under multigenic control, (ii) the xid locus on the X chromosome influences susceptibility to cryptococcosis, and (iii) xid mice behave differently than CBA/Ca mice in their organ response during the course of the infection.  相似文献   

12.
The effects of polyclonal antibodies to mouse serum components on the primary humoral immune response of mice in vivo were studied. It was observed that rabbit IgG to complement component C3 and albumin and mouse IgG to C5, but also heat-aggregated non-immune rabbit IgG, enhanced the agglutinating antibody response to sheep erythrocytes (SRBC). Since the increase in response was only observed when antigen and antibodies were administered via the same route (i.p.), immunological adjuvant activity was implicated. Ineffectiveness of anti-C5 IgG in C5-deficient mice indicated that the antibody-induced adjuvant activity is mediated by in vivo formed immune complexes (IC). The adjuvant activity of IC was reduced by selective C3-depletion of animals, pointing to a requirement of C3. The effect of variations in other parameters was studied with anti-C3 and anti-C5 IgG as immunoadjuvant. The immunostimulatory effect was most pronounced when the antibodies were administered simultaneously with or shortly before antigen. Treatment of animals with antibodies one or two days before antigen, however, resulted in a suppression of the response. The response to thymus-independent antigens was not enhanced by anti-C3 nor by anti-C5 IgG. Optimal adjuvant activity of anti-C3 IgG was observed at low antigen doses. Nude mice were insensitive to the immunopotentiating effect of anti-C3 and so was the F1 progeny of BALB/c male and CBA/N female mice expressing a B-cell maturation defect. C5 deficiency and lipopolysaccharide (LPS) non-responsiveness did not affect the adjuvant activity of in vivo formed C3-anti-C3 IC.  相似文献   

13.
F J Gomez  A M Gomez    G S Deepe  Jr 《Infection and immunity》1991,59(12):4459-4464
We reported previously that a detergent extract of the cell wall and cell membrane of Histoplasma capsulatum yeast cells contains antigens recognized by T cells. In T-cell immunoblot analysis, a region encompassing 62 kDa was stimulatory for an H. capsulatum-reactive T-cell line and T-cell clones derived from C57BL/6 mice. In this study, we isolated a 62-kDa band, termed HIS-62, from electrophoresed cell wall and cell membrane of H. capsulatum yeast cells and examined its antigenicity and immunogenicity. C57BL/6, BALB/c, and CBA/J mice that were immunized with viable H. capsulatum yeast cells mounted a delayed-type hypersensitivity response to HIS-62 that was stronger than that of normal controls. Spleen cells from each strain of mouse immunized with viable yeast cells proliferated vigorously in response to HIS-62; conversely, splenocytes from control animals did not recognize this antigen. A T-cell line and 5 of 5 T-cell clones from C57BL/6 mice, 10 of 15 BALB/c T-cell hybridomas, and 8 of 12 CBA/J T-cell hybridomas recognized HIS-62. A cutaneous delayed-type hypersensitivity response to the antigen was apparent in each strain of mouse that was injected with 80 micrograms of HIS-62 mixed with Freund adjuvant. In addition, spleen cells from HIS-62-immunized mice proliferated in vitro in response to this antigen. Vaccination of each strain of mouse with 80 micrograms of HIS-62 conferred protection against a lethal intravenous challenge with H. capsulatum yeast cells. Thus, HIS-62 appears to be an important target of the cellular immune response to H. capsulatum and induces a protective immune response in mice.  相似文献   

14.
We previously reported that administration of a low molecular weight (MW=800) synthetic polymer, NED 137, significantly increases humoral and cellular immune responses in the rat. The effect of NED 137 on the murine humoral response to T-dependent (TD) and T-independent (TI) antigens was studied in C57 BL/6, CBA/J and Balb/c mice. The TD antigens (SRBC, DNP-DA with adjuvant) or TI antigen (DNP-Ficoll) were administered simultaneously with NED 137. The polymer significantly increased the direct PFC response to all antigens tested in normal mice. However, it could not restore the PFC response to SRBC in athymic (nu/nu) mice. The effect of NED 137 on accessory cells was studied by the assessment of the in vitro response to SRBC in normal and macrophage-depleted rat spleen cultures. The polymer stimulated both, the primary and secondary IgM response and its immunopotentiating activity was the greatest in macrophage-depleted spleen cell preparations. The lack of effect of NED 137 in systems devoid of functional T cells, dependency on and specificity for a sensitizing antigen and its ability to stimulate a secondary response suggest that this polymer does not act as a “conventional” B-cell polyclonal activator.  相似文献   

15.
Abstract

We previously reported that administration of a low molecular weight (MW=800) synthetic polymer, NED 137, significantly increases humoral and cellular immune responses in the rat. The effect of NED 137 on the murine humoral response to T-dependent (TD) and T-independent (TI) antigens was studied in C57 BL/6, CBA/J and Balb/c mice. The TD antigens (SRBC, DNP-DA with adjuvant) or TI antigen (DNP-Ficoll) were administered simultaneously with NED 137. The polymer significantly increased the direct PFC response to all antigens tested in normal mice. However, it could not restore the PFC response to SRBC in athymic (nu/nu) mice. The effect of NED 137 on accessory cells was studied by the assessment of the in vitro response to SRBC in normal and macrophage-depleted rat spleen cultures. The polymer stimulated both, the primary and secondary IgM response and its immunopotentiating activity was the greatest in macrophage-depleted spleen cell preparations. The lack of effect of NED 137 in systems devoid of functional T cells, dependency on and specificity for a sensitizing antigen and its ability to stimulate a secondary response suggest that this polymer does not act as a “conventional” B-cell polyclonal activator.  相似文献   

16.
A method, using an immunodeficient mouse strain, for the production of monoclonal antibodies directed exclusively against the proteins in an antigen mixture also containing immunodominant LPS, is described. Male (CBA/N x BALB/c) F1 mice were immunized with an outer envelope antigen mixture from Leptospira interrogans strain Wijnberg containing both lipopolysaccharides and proteins. The immune response in these mice was shown to be predominantly directed against protein antigens. Hybridoma cell lines were generated by fusing spleen cells from a (CBA/N x BALB/c) F1 mouse with BALB/c Sp2/0 plasmacytoma cells. Hybridoma cell lines producing monoclonal antibodies reacting with the outer envelope preparation were identified by ELISA. All epitopes recognized by the monoclonal antibodies are sensitive to proteinase K degradation and resistant to oxidation by periodate indicating that they are located on proteins. All epitopes are located on a 35 kDa protein and specific for the pathogenic L. interrogans species.  相似文献   

17.
CBA/N mice have an X-linked B-cell defect which prevents them from responding to non-mitogenic thymus-independent (TI-2) antigens such as haptenated Ficoll. The CBA/N mice do, however, respond to another group of thymus-independent (TI-1) antigens among which are haptenated liposomes. The F1 male progeny of CBA/N female mice express the same characteristics. Hapten-specific plaque-forming cell (PFC) responses to haptenated proteins (thymus-dependent, TD, antigens) by CBA/N mice and CBA/N x C3H/HeN F1 male mice can be blocked by concomitant exposure to TI-2 antigens bearing the same hapten. Simultaneous exposure to haptenated liposomes (TI-1 antigen) and TD antigens, however, results in a synergistic response to the hapten if the antigens share common epitopes. The tripeptide-enlarged hapten dinitrophenyl-beta-alanylglycylglycine (J), conjugated to phosphatidyl-ethanolamine (PE) and incorporated into liposomal model membranes, was used throughout the experiments. In F1 male mice the moderate responses to TD antigens could be restored to values equivalent to those seen in F1 female mice. This adjuvant effect of haptenated liposomes is hapten-specific, time-dependent, and restricted to certain structural forms of the liposomes.  相似文献   

18.
A. Ghaffar  K. James 《Immunology》1973,24(6):1075-1085
The effect of a single batch of horse anti-mouse thymocyte globulin on the immune response to type III polysaccharide antigen has been investigated in 2–3-month-old male A/HeJ, C57B1, BALB/c, DBA/1, CBA and C3H mice. In almost all cases the intraperitoneal administration of 5 mg of this material on days –4 and –2 significantly suppressed the immune response to 0.1, 1.0 and 5.0 μg of antigen injected i.v. on day 0. Further studies undertaken in BALB/c mice indicated that effective suppression of the immune response to type III polysaccharide antigen could also be achieved by injecting 5 mg of this product (i.p.) some 15–30 minutes prior to antigenic challenge. Preliminary cell reconstitution studies in antilymphocytic antibody-treated CBA mice indicate that the ability to respond to type III polysaccharide can be partially restored by the injection of syngeneic thymocytes, bone marrow cells or spleen cells.  相似文献   

19.
Experiments performed on male CBA mice immunized with sheep erythrocytes at a dose of 5·108 cells showed that the selective agonist of serotonin 5-HT1A receptors 8-OH-DPAT (1 mg/kg) suppresses the immune response in aggressive animals. In mice demonstrating the submissive type of behavior, formed during 10 days of experience of defeats, activation of 5-HT1A receptors with 8-OH-DPAT had no effect on the immune response. However, treatment with the selective 5-HT1A receptor blocker WAY-100635 stimulated the immune response, but only in submissive mice. These data lead to the conclusion that activation and blockade of 5-HT1A receptors have different effects on the immune response in CBA mice depending on the initial emotional state of the animals, due to different activities of neurotransmitter systems, particularly the serotoninergic, in aggressive and submissive mice. __________ Translated from Zhurnal Vysshei Nervnoi Deyatel’nosti imeni I. P. Pavlova, Vol. 55, No. 4, pp. 567–572, July–August, 2005.  相似文献   

20.
Injection of polyvinylpyrrolidone (synthetic type 2 T-independent antigen) stimulated the efficiency of clone-forming efficiency and the content of stromal precursor cells in CBA mice in the femoral bone marrow (almost 3-fold) and in the spleen (by 1.7 times) with the peak within 24 h and normalization by day 3 after immunization. The expression of IL-6, IL-8, and TNF-α genes in bone marrow and spleen cultures from immunized animals appeared on day 1 and disappeared on day 3. Hence, stimulation of stromal tissue in response to polyvinylpyrrolidone immunization was significantly less pronounced in comparison with immunization with S. typhimurium antigens. The counts of stromal precursor cells in these organs did not increase in CBA/N mice not responding to polyvinylpyrrolidone because they had no xidmutation in Brutton’s tyrosine kinase (Btk) gene, and the proinflammatory cytokine genes expression in primary cultures derived from these animals did not increase either. These data indicated that the degree of stromal tissue stimulation in immunized mice correlated with the immune response intensity. This indicated a close relationship between the stromal tissue and immune system. Stromal tissue seemed to be stimulated not only and not so much through the stromal cell Toll-like receptors, but mainly through interactions of immunocompetent and stromal cells, the former presumably playing the leading role in this process.  相似文献   

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