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1.
The role of chemotherapy in influencing tumor-specific immunity to a mouse mammary adenocarcinoma was investigated. By studying different stages of tumor growth we were able to identify several factors important to drug-induced tumor regression: (1) antibody response, (2) delayed hypersensitivity, (3) sensitivity of tumor cells to immune attack and (4) tumor burden. The presence of tumor-specific delayed hypersensitivity and circulating antibody as well as specifically armed monocytes in the tumor mass characterize the T1699 adenocarcinoma. Successful chemotherapy had previously been shown to depend on prior establishment of the above immune responses. Treatment with alkylating agents was marked in all animals by abrogation of a humoral response to the tumor when drug was given early (day 7), and was associated with poor chemotherapeutic results. Later treatment (day 10) was associated with depression of antibody titers only in the minority of animals not responding to drug and prolongation of the delayed hypersensitivity response in all treated animals. Tumors recurring following initial drug-induced regression were marked by lack of delayed hypersensitivity in the host, lack of drug response and suppression of humoral immunity following treatment. Successive passage of cells from these resistant tumors led to decreasing sensitivity to chemotherapy despite established immunity on the part of the host. The selection of tumor cells resistant to immune destruction rather than drug resistance per se appeared to pay a role. Melphalan was thus able to affect both favorably and adversely the immune factors important to drug-induced regression.  相似文献   

2.
Intercellular adhesion molecules play an important role in the generation of T lymphocyte-mediated immune responses. Here, we describe a novel accessory molecule, DNAX accessory molecule-1 (DNAM-1), that is constitutively expressed on the majority of peripheral blood T lymphocytes. DNAM-1 is a 65 kDa transmembrane glycoprotein consisting of 318 aa including two immunoglobulin-like domains. Anti-DNAM-1 monoclonal antibody (MAb) inhibits T and NK cell-mediated cytotoxicity against a variety of tumor cell targets and blocks cytokine production by alloantigen-specific T cells. In addition, DNAM-1 is a tyrosine-phosphorylated signal-transducing molecule that participates in primary adhesion during cytotoxic T lymphocyte (CTL)-mediated cytotoxicity.  相似文献   

3.
Levamisole, a potentiator of cell-mediated immunity, has been reported to increase survival in patients with resectable carcinoma of the lung. Cell-mediated immunity can be measured in vitro by the leukocyte migration inhibition test. We have previously reported that this test detects cell-mediated immunity to human lung tumor antigens. In the present studies, patients with lung cancer were treated with Levamisole. Their leukocytes were evaluated in the leukocyte migration inhibition assay before, during, and following Levamisole therapy. Small increases in cell-mediated immunity were observed when patients had a high pre-existing tumor immunity. When tumor-associated reactivity was absent prior to therapy, larger increases were measured. Although Levamisole is a nonspecific immunostimulant, these data indicate that in vitro anti-tumor immune responses are enhanced by Levamisole therapy. Augmentation of cell-mediated immunity to tumor antigens may explain the clinical benefits of Levamisole therapy.  相似文献   

4.
The anti-pneumococcal antibody response was studied in young (5-week-old) and adult (10-week-old) BALB/c and CBA/J mice and in adult (9-10-week-old) and old (12-, 18- and 24-month-old) AB6F1 and B6D2F1 mice after s.c. immunization with a 23-valent pneumococcal polysaccharide vaccine. Both young and adult mice showed a significant IgM antibody response to the vaccine 6 days after immunization with 1-11 micrograms antigen. There were significant immune responses to serotypes 1, 2, 4 and 7F in contrast to small responses to serotypes 14, 19F and 23F after immunization with the vaccine. One month after immunization, there were only marginal differences in IgM anti-pneumococcal antibody levels to the vaccine (anti-PPS) between immunized and unimmunized BALB/c mice, whereas in CBA/J mice the anti-PPS remained higher in immunized than in unimmunized mice. Immunization of old mice induced a significant IgM antibody response 6 days after immunization, but the anti-PPS thereafter decreased rapidly towards preimmunization values in AB6F1 mice. A significant IgG anti-PPS was not detected in any of the mice studied. The IgA anti-PPS tended to vary over time with no consistent pattern. It is important to carefully consider age and strain of the mice used when studying the immune response to pneumococcal polysaccharide antigens.  相似文献   

5.
Substantial evidence indicates that innate and acquired defense mechanisms are lowest from 3 wk precalving to 3 wk postcalving. This lowered responsiveness includes aspects of systemic and mammary gland immunity that may account, at least in part, for the increased incidence of peripartum disease. The physical and metabolic stresses of pregnancy, calving, and lactation may contribute to this decrease in host resistance and the subsequent increase in disease incidence. However, variation among cows in their host resistance mechanisms suggests that genotype and phenotype may possibly be used to identify cows that are able to mount beneficial immune responses over the periparturient period. Our own studies suggest that cows may be categorized as high or low responders based on the peripartum antibody responses to ovalbumin and Escherichia coli J5. Low responders were hyporesponsive to these test antigens and had a higher incidence of peripartum diseases, particularly mastitis. In many species, a functional link exists between the immune and endocrine systems, and, during periods of stress or physical injury, neuropeptides and neuroendocrine hormones function as immunomodulators. Initial investigations of peripartum cows reveal positive relationships between growth hormone kinetics and profiles of antibody response. Whether hormone fluctuations during the periparturient period are responsible for the alterations observed in immune responsiveness remains uncertain.  相似文献   

6.
The susceptibility of NK cells and immune cytotoxic T-cells to treatment with (a) monoclonal anti thy 1.2 antibodies from hybridoma HO13-4, (b) rabbit anti-mouse T-cell antiserum and (c) gamma globulins prepared from AKR/J anti C3H/HeJ antiserum was studied in the presence of rabbit complement. Monoclonal anti thy 1.2 antibody treatment completely abolished the cytotoxic activity of immune T-cells derived from C57BL/6J mice (H-2b) immunized with (C57BL/6J x DBA/2)F1 spleen cells (H-2bd) against P815 (H-2d) target cells. The same treatment had no significant effect on the NK activity of spleen cells from unimmunized mice against YAC target cells. Rabbit anti-mouse T-cell and mouse anti theta antisera also abrogated completely the immune T cell activity of spleen cells. This treatment however also resulted in a partial loss of NK activity. These results indicate that conventional anti theta antisera contain antibodies which recognize antigenic specificities on T-cells as well as on a population of NK cells. The cross reactivity is not a result of thy 1.2 antigen expression on NK cells and T-cells as recognized by the monoclonal antibodies. The specificity recognized by the monoclonal antibody (HO13-4) is only expressed on T-cells.  相似文献   

7.
Several correlative experimental approaches have provided evidence that polyclonal serum natural antibodies (NAb) participate in the defense against small syngeneic tumor foci in vivo. The threshold subcutaneous tumor inoculum model of incipient neoplasia has consistently revealed an inverse relationship between tumorigenicity in vivo and the NAb binding capacity of the tumor injected or the anti-tumor NAb levels of the recipient animals, including B cell-deficient mice bearing the xid mutation of the CBA/N mouse strain. Now passive i.v. administration of whole normal syngeneic serum NAb in bolus injections, given I each day beginning on day -2, -1 or 0 prior to the threshold s.c. challenge of xid-bearing CBA/N or male (CBA/N x CBA/J)F1 mice with syngeneic RI-28 lymphoma cells, consistently and significantly reduced their tumorigenicity assayed as tumor appearance and latency. Three similar injections of an ammonium sulfate-precipitated fraction of whole serum NAb also reduced tumor frequency and latency, while a combination of purified IgG and IgM NAb reduced the appearance of tumors slightly and increased the survival of recipients. The reconstitution of the xid-defect in anti-tumor NAb provides more direct evidence to substantiate a role for NAb in the defense against early tumor development in vivo and establishes a model for the dissection of the in vivo mechanisms of the NAb anti-tumor activity.  相似文献   

8.
Recurrence of colorectal carcinomas occurs in about 50% of the cases with localized neoplasia. It is understood that the tumor recurrence is due to residual micrometastases not found during surgery or extraregional (peripheral blood or bone marrow). We developed a procedure to detect non-visible, abdominal metastases using a radiolabeled anti-tumor cell antibody injected before the operation (radioimmunoguided surgery RIGS). However, even with the best technique, it is not possible to remove all micrometastasis if a hematogenic dissemination happens. Based on the knowledge of disturbing humoral immune reaction is mounted against shed tumor associated antigens (TAA), we developed a new method to reduce and correct the B cell response and B cell recruitment due to chronic TAA immun complex presentation on follicular dendritic cells (immune corrective surgery, ICS). This method is based on a selective lymphadenectomy. The target lymph nodes were those loaded with TAA-immune complex. The detection method used was the injection of radiolabeled antibody able to recognize the immune complex. From 20 patients (stage I, II and III) treated with ICS, 17 survived more than 5 years 'showing a statistically significant increase of survival compared to patients treated with standard procedures. In conclusion, these data show that surgery of colorectal cancer should be selectively extended to specific anatomical regions in order to remove hidden micrometastases, and more importantly, correct postoperative immune processes that could suppress the T cell response against residual tumor cells.  相似文献   

9.
Our earlier work had demonstrated a fine-specificity idiotype in anti-NP antibodies of C57Bl/6 mice. It was controlled by a VH gene (VH-NPb). The idiotype could be demonstrated in all anti-NP of the C50Bl/6 mice (IgG, IgA, IgM including natural anti-NP). The VH-NPb gene is condominant with CBA allele F1 hybrid mice in the production of natural antibodies but dominant over the CBA allele in immune antibody formation (92% of F1 mice were like C57Bl/6). Probably the product of this gene has a higher affinity for NP than the average affinity of idiotype-negative antibody in the F1 hybrids. Both the codominance in natural antibodies and the dominance in immune antibodies had the peculiar characteristic that genotypically identical individuals varied a great deal. The share of idiotype-positive antibody in the total natural anti-NP titre of (C57Bl/6 x CBA)F1 mice varied from less than 33% to more than 67%. In immune antibodies individual differences were still greater, in ca 92% of mice only idiotype-positive anti-NP could be detected and in ca 8% only idiotype-negative antibody was detectable. Only few F1 hybrid mice had detectable amounts of both types. Homozygous mice of the LP strain behaved in all aspects like the F1 mice. Of their natural anti-NP titres 50% were due to idiotype-positive antibody and in the immune antibodies the figure was 86%. Individual non-immune sera again contained varying mixtures of idiotype-positive and idiotype-negative antibody, but immune sera contained only one or the other type. The third allotype b strain tested, C57Bl/Ka, took an intermediary position between LP and C57Bl/6. Ca 70% of natural anti-NP titres were due to idiotype-positive antibody but all immune anti-NP was idiotype-positive.  相似文献   

10.
C57BL/6 (B6) and C57BL/6.Fv-1n (B6.Fv-1n) mice mount AKR/Gross murine leukemia virus (MuLV)-specific cytolytic T lymphocyte (CTL) responses following primary and secondary stimulation with AKR/Gross MuLV-induced tumor cells. In contrast, mice exposed to infectious virus rather than virus-infected cells generate little, if any, antiviral CTL activity. In this report, we show that inoculation of B6 or B6.Fv-1n mice with MuLV prior to priming with H-2-matched AKR/Gross virus antigen-positive tumor cells resulted in a profound inhibition of the virus-specific CTL response. Antiallogeneic major and minor histocompatibility antigen-specific CTL responses were not significantly diminished in MuLV-infected mice. The AKR/Gross MuLV-specific CTL response in B6 mice was inhibited by NB-tropic (SL3-3NB, Friend and Moloney), but not N-tropic (AKR623) MuLV, suggesting that productive infection of host cells was required. We were unable to inhibit the in vitro generation of virus-specific CTL by adding modulator cells from virus-infected mice to mixed lymphocyte-tumor cell cultures (MLTC) of spleen cells from uninfected animals. We also failed to augment CTL generation in MLTC from virus-infected animals by adding exogenous IL-2 or CD4+ lymphocytes from uninfected, tumor-primed mice. Taken together, the data suggested that the inhibition resulted from either a direct or an indirect effect on the in vivo priming of virus-specific CD8+ cells. It is therefore interesting that MuLV such as Friend and Moloney, which do not encode the immunodominant epitope recognized by anti-AKR/Gross MuLV CTL, are nonetheless able to specifically inhibit this response. These results demonstrate a potentially important mechanism by which retroviruses may escape CTL-mediated immunity.  相似文献   

11.
In the AKR.Fv-1b congenic strain the Fv-1n allele of the AKR/J mice was substituted with the Fv-1b allele, thereby limiting viral replication and spread of the endogenous N-tropic murine leukemia virus. As a result of this genetic change AKR.Fv-1b mice develop a low spontaneous incidence (7%) of T-cell lymphomas and about 28% of Ly-1+ B-cell lymphomas are observed in old mice. Characteristic changes in thymus subpopulations of AKR/J mice (related to the formation of the dual tropic mink cell focus inducing (MCF) type virus in the thymus) were not observed in the thymus of AKR.Fv-1b mice. In contrast to the low susceptibility to spontaneous T-cell lymphoma development, these mice were highly sensitive to fractionated irradiation or to radiation leukemia virus (a mixture of N- and B-tropic viruses) induced T-cell lymphoma. Potential lymphoma cells (that would ultimately develop into Ly-1+ B-cell lymphomas) were demonstrated in bone marrow and spleens of 16-24-month-old mice. Analysis of the Ly-1+ IgM+ B-cell population in spleens of 18-month-old mice revealed a significant increase in this population (35% versus 2% in young spleens). The spontaneous Ly-1+ B-cell lymphoma incidence could be enhanced (up to 77%) by in vivo administration of anti-CD8 monoclonal antibody or IL-4 to 18-month-old mice. Virological analysis of T/B-cell lymphomas for class I MCF viruses indicated that Class I MCF development was tightly correlated with T-lymphoma development (except radiation induced tumors that showed no MCF provirus involvement). In contrast, Ly-1+ B-cell lymphoma development was independent of Class I MCF pathogenic virus involvement.  相似文献   

12.
The ability of alloantibody to suppress the humoral immune response to transplantation antigens in the mouse has been studied in relation to its specificity. It was found that antibody was able to suppress the cytotoxic antibody response to determinants other than those against which it was directed when there was some common antigenicity between the different H-2 types used for immunising. It was also found that suppression of the response to both parental haplotypes of an F1-hybrid cell could be achieved by antibody to only one parental haplotype, the antibody being made in the other parental strain to avoid any possibility of cross-reactivity. Such nonspecific immunosuppression was not achieved when cells of the two parental strains were administered mixed together.  相似文献   

13.
In this study we investigated the relationship between binding of anti-tumor antibodies by polyoma-virus-induced SEYF- a tumor cells and the expression of immune-complex receptors on these cells. It was shown that in vivo propagated cells became progressively coated with IgG. The increase in the IgG coating of SEYF-a cells, occurring during the second week of propagation, was directly correlated with an increase in the coating of cells with potentially cytotoxic anti-tumor antibodies. The activity of these antibodies was demonstrated by cell lysis following addition of exogenous complement. Cell populations propagated in vivo for longer periods (3 weeks or more) became less sensitive to exogenous complement although their IgG coating remained high, and although higher titers of anti-tumor antibodies could be eluted from them. This indicated that antibodies coating young tumor cell populations have the capacity to activate complement whereas those coating older tumor cell populations are incapable of complement activation. Previous findings that SEYF-a cell populations are able to bind unrelated immune complexes were confirmed in the present study. We also found that the capacity of these populations to bind such unrelated complexes decreased with propagation time in vivo. The involvement of anti-tumor antibodies in this phenomenon was indicated by the finding that such antibodies inhibited binding of unrelated immune complexes by young cells but not by old cells. Furthermore, treatments causing dissociation of Ig from the cell surface restored, to some extent, the capacity of anti-tumor antibodies to inhibit immune complex binding by old SEYF-a populations.  相似文献   

14.
15.
Cell-mediated immunity in rheumatoid arthritis (RA) was assessed by skin testing with six antigens in 107 patients, 94 of whom were age, sex, and race-matched with healthy individuals or patients with diseases unrelated to immunological abnormalities. 20% of RA patients were anergic. Impaired cell-mediated immunity in the RA patients was manifested by a decrease in the magnitude of skin reactivity as well as a decrease in the incidence of positive reactions to multiple antigens. Depression in cell-mediated immunity was related to age but not to sex, duration of disease, or disease activity. A slight correlation was found between absolute peripheral lymphocyte counts and the number of positive skin tests, and was confirmed by finding an association between lymphocyte counts and the size of skin reactions. A correlation was also found between lymphocyte counts and disease activity. Four explanations of the observed depression in cell-mediated immunity in RA were considered: (1) a preoccupation of the immune mechanism of the host with cell-mediated immunity reactions related to the pathogenesis of the disease; (2) a depression of cell-mediated immune reactivity by a virus infection; (3) depression of cell-mediated immunity by therapy; and (4) immune complex suppression of cell-mediated immunity. No effect of gold therapy was found. The near universal use of salicylates or other anti-inflammatory drugs did not permit investigation of the effect of these drugs on cell-mediated immunity.  相似文献   

16.
Using a longitudinal, prospective adoption design, the authors of this study examined the effects of the environment (adoptive parents' depressive symptoms and responsiveness) and genetic liability of maternal depression (inferred by birth mothers' major depressive disorder [MDD]) on the development of fussiness in adopted children between 9 and 18 months old. The sample included 281 families linked through adoption, with each family including 4 individuals (i.e., adopted child, birth mother, adoptive father and mother). Results showed that adoptive mothers' depressive symptoms when their child was 9 months old were positively associated with child fussiness at 18 months. A significant interaction between birth mothers' MDD and adoptive mothers' responsiveness indicated that children of birth mothers with MDD showed higher levels of fussiness at 18 months when adoptive mothers had been less responsive to the children at 9 months. However, in the context of high levels of adoptive mothers' responsiveness, children of birth mothers with MDD did not show elevated fussiness at 18 months. Findings are discussed in terms of gene–environment interactions in the intergenerational risk transmission of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
Tumor growth induces phenotypic and functional changes among splenic T cells and macrophages (M phi) that contribute to the immunosuppression observed in tumor-bearing hosts (TBH). These changes partly arise through alterations in immune cell production of and responsiveness to cytokines. Granulocyte-macrophage colony-stimulating factor (GM-CSF) is an important T cell- and M phi-derived cytokine that is produced during normal host immunogenic challenge, but it's involvement during cancer is poorly defined. In contrast, interleukin-10 (IL-10) is an inhibitory cytokine that is produced by immune cells as a deactivation factor. IL-10 can disrupt GM-CSF synthesis and may be associated with tumor-induced changes in cytokine synthesis. We determined if tumor growth alters T-cell and M phi synthesis of and responsiveness to GM-CSF, and if these alterations occur because tumor growth heightens immune cell sensitivity to IL-10. Tumor growth significantly decreased T-cell synthesis of GM-CSF during activation by concanavalin A, and TBH T cells were more susceptible to GM-CSF synthesis inhibition by IL-10 than their normal host (NH) counterparts. This suppression was observed using both unseparated splenic lymphocyte preparations and purified CD4+ and CD8+ T cells. Similarly, TBH M phi (both splenic and peritoneal) produced less GM-CSF than NH M phi during activation by lipopolysaccharide. Tumor growth also altered major histocompatibility complex (MHC) class II- M phi GM-CSF synthesis. TBH M phi were more susceptible to GM-CSF synthesis inhibition by IL-10 than their NH counterparts. Although TBH T cells demonstrate less proliferation than NH T cells during activation, tumor growth did not compromise T-cell responsiveness to GM-CSF. However, tumor growth did increase TBH T-cell susceptibility to inhibition of proliferation by IL-10. Tumor growth suppressed M phi responsiveness to GM-CSF, and IL-10 further decreased M phi responsiveness to GM-CSF. Collectively, these results suggest that T cell and M phi production of and responsiveness to GM-CSF is disrupted during tumor growth, and that TBH T cells and M phi are more susceptible to the suppressor activity of IL-10 than their NH counterparts.  相似文献   

18.
The immune system of a case of Cogan's syndrome was investigated. A transient depression of the cell-mediated immunity was found. Thus, during the acute stage of the disease, there was a depression of the cutaneous delayed hypersensitivity reaction to PPD and a decrease in the number of T cells. There were also signs of complement consumption. A possible pathogenesis based on immune complexes due to a preceding viral infection is discussed.  相似文献   

19.
A major goal of tumor immunotherapy is the effective eradication of established metastases associated with the induction of a T cell-mediated protective immunity. We achieved this in a poorly immunogenic murine neuroblastoma model by gene therapy with a single chain interleukin 12 (scIL-12) fusion protein that assures equal expression of its p35 and p40 subunits. Thus, NXS2 hybrid neuroblastoma cells (C1300 x dorsal root ganglion cells), which form experimental bone marrow and liver metastases in syngeneic A/J mice, were transduced with a gene encoding murine interleukin 12, monomerized by introduction of a protein linker between the p35 and p40 protein chains of this heterodimeric cytokine. We demonstrate for the first time that subcutaneous vaccination with these transduced cells induces a protective immunity, as indicated by the complete absence of liver and bone marrow metastasis after challenge with NXS2 wild-type tumor cells. Furthermore, vaccination of animals with established liver and bone marrow metastases completely eradicated liver metastases and suppressed bone marrow metastases. The local and systemic immune response against scIL-12-transduced NXS2 cells is largely dependent on CD8(+) T cells. This was demonstrated in vivo by depletion of immunocompetent A/J mice with monoclonal anti-CD4 and anti-CD8 antibodies and in vitro by specific major histocompatibility complex, class I-restricted CD8(+) T cell-mediated killing of NXS2 and their parental C1300 neuroblastoma cells. In conclusion, we demonstrate successful anti-tumor immunotherapy with an scIL-12 fusion protein that could facilitate clinical application of interleukin 12 gene therapy.  相似文献   

20.
In a previous work we provided preliminary evidence of the existence of a putative tumor suppressor gene region on the distal part of chromosome 4 in gamma-radiation-induced T-cell lymphomas of (C57BL/6J x RF/J) F1 hybrid mice. This region, named as TLSR2 (Thymic Lymphoma Suppressor Region 2), was located centered at D4Mit54. A more detailed allelotype analysis in the mentioned tumors with new informative microsatellites on distal chromosome 4 region, as well as in thymic lymphomas induced with gamma-rays in F1 hybrids generated from reciprocal crosses between the strains C57BL/6J and BALB/cJ, and having in mind the new map position of D4Mit205b, allowed us to confirm the existence of TLSR2 and to define it more precisely as centered at D4Mit205b. In addition, we identified a new candidate region, named as TLSR3 (Thymic Lymphoma Suppressor Region 3), located between the Mom-1 locus and D4Mit68, as the site of another putative tumor suppressor region involved in thymic lymphomagenesis.  相似文献   

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