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1.
Forty patients with hematologic malignancy or aplastic anemia were given allogeneic marrow after conditioning with high-dose cyclophosphamide alone or in combination with total body irradiation. Between 28 and 3857 days after transplantation, their peripheral blood mononuclear leukocytes were tested for reactivity in indirect cell-mediated lympholysis against normal leukocytes from unrelated individuals, and the results were compared to those with cells from their healthy marrow donors. An impairment of cell-mediated lympholysis was found with cells from most patients with acute and chronic graft-vs-host disease (GVHD) whereas cells from most short-term and long-term patients without GVHD had cell-mediated lympholysis reactivity comparable to that of cells from the marrow donors. When interleukin 2 was added to the mixed leukocyte cultures during the sensitization phase, the impaired cell-mediated immunity of cells from most short-term patients with acute GVHD, but not that of cells from most patients with chronic GHVD, could be restored to normal levels. These results suggest the impairment of cell-mediated immunity seen in cells of short-term patients with acute GVHD is attributable to helper cell defects or to ineffective communication between antigen-presenting cells and helper T cells. The impairment in cell-mediated immunity seen in patients with chronic GVHD, however, may reside on the effector cells (or their precursors) or may be due to the presence of suppressor cell activity.  相似文献   

2.
The pattern of immunodeficiency in plasmacytoma-bearing mice appears to be unique. Mice bearing these tumors exhibit a severe impairment in their ability to mount a primary immune response to thymus-dependent and -independent antigens. However, cell-mediated immune functions in these mice apparently remain intact. Thus, when T cell activity of lymph node cells from plasmacytoma-bearing mice was tested in vivo by sensitization with dinitrofluorobenzene and in vitro by responsiveness to phytohemmagglutinin, allogeneic cells, and dinitrobenzene sulfonate, cell-mediated immunity was found to be normal.  相似文献   

3.
Sporotrichosis is characterized by a wide range of clinical manifestations from mild fixed cutaneous forms to systemic dissemination of the disease, despite an apparent regular pattern of virulence of the etiological agent, S. schenckii. These facts suggest that immunological mechanisms of the host could play an important role on the pathogenesis of the mycosis. On this basis, an immunologic survey was carried out in patients with lymphocutaneous sporotrichosis. Cell-mediated immunity was evaluated by means of lymphocyte transformation stimulated with phytohaemagglutinin and the response to several intradermal reaction antigens. Lymphocyte blastic transformation was normal as compared with a control group. All patients were positive at least against one of the antigens tested. These results indicate that this group of patients did not show any cell-mediated immunity deficiency. Serum immunoglobulins (IgG, IgM, IgA), and C3 measured to evaluate humoral immunity, were also within normality. Since many cases of sporotrichosis cure with the administration of potassium iodine, whose mechanisms of therapeutic activity are unknown, a possible impairment in the management of iodine was investigated, with the premise that iodine enhances the host defenses rather than acting against the fungus. Thyroid function tests performed in all patients to support this hypothesis, gave normal results. These data permit to conclude that susceptibility to sporotrichosis in the affected patients does not depend on gross abnormal humoral and/or cell-mediated immunity, and their response to potassium iodine is not related to deficient thyroid function.  相似文献   

4.
Factors contributing to the impairment of cell-mediated immunity in cancer patients were studied. Normal plasma enhanced the PHA-induced transformation of cancer lymphocytes. Cancer plasma suppressed the transformation of normal lymphocytes. The plasma factor(s), which might play an important role in the impairment of cell-mediated immunity in cancer, was further characterized to be heat-labile, being completely destroyed at 56 degrees C for 30 minutes. It was present on the surface of T lymphocytes, and was partially removable by digestion with 0.05% Bacto-trypsin. Moreover, the percentage of T cells in the peripheral blood of cancer patients was lower than that of normal as determined by the anti-human thymocyte serum cytotoxicity test and the spontaneous rosette forming test.  相似文献   

5.
Cell-mediated immunity in nutritional imbalance   总被引:9,自引:0,他引:9  
Marked perturbations of cell-mediated immunity are observed in nutritional imbalance, both undernutrition and overnutrition. Individuals with protein-energy malnutrition show consistent impairment of cutaneous delayed hypersensitivity and a reduced number of circulating T lymphocytes. Variable changes in lymphocyte stimulation response in vitro to mitogens and antigens are seen. There is a relative increase in the number of "null" cells and high levels of leukocyte terminal deoxynucleotidyl transferase activity. These findings suggest impaired differentiation of T cell precursors, which may be the direct result of reduced thymic hormone activity. Alterations in the production of lymphokines are not consistent. Infants with intrauterine growth retardation show a marked and long-lasting deficit in cell-mediated immunity. Specific nutrient deficiencies vary in their ability to influence cell-mediated immunity and the mechanisms underlying the immunologic abnormalities. Among others, zinc and pyridoxine deficiencies are associated with marked immunodepression. Obesity also is associated with alterations in cell-mediated immune responses. This has been observed in man, in genetically obese mice, and in states of excess intake of lipids, vitamins, minerals, and a trace elements. Nutritional modulation of cellular immunity is an important determinant of morbidity in several systemic disorders.  相似文献   

6.
We sought to identify imbalances of immune regulatory cells that might contribute to the depression of cell-mediated immunity that occurs during an episode of herpes zoster. Peripheral blood mononuclear cells (PBMC) were obtained from patients with herpes zoster during the acute (less than 7 days after disease onset) and convalescent (more than 10 days after disease onset) phases of illness and from healthy seropositive donors. The PBMC were analyzed for: lymphoproliferative responses to varicella-zoster virus (VZV) antigens, Leu-3 (helper/inducer):Leu-2 (cytotoxic/suppressor) ratios, and percentages of suppressor cells as defined by coexpression of the Leu-2 and OKM1 antigens. Significantly depressed proliferative responses of VZV antigens and Leu-3:Leu-2 ratios, and increased percentages of Leu-2+ OKM1+ suppressor cells were observed in PBMC of acute phase herpes zoster patients as compared with the PBMC of convalescent patients or healthy donors. These differences were also observed in individual patients sequentially studied during both phases of disease. Cryopreserved acute phase PBMC suppressed the proliferative response of autologous convalescent phase PBMC to VZV antigens, but not to herpes simplex virus (HSV) antigens. The acute phase PBMC suppressor cell was radiation sensitive and was identified as a Leu-2+ cell by fluorescence-activated cell sorting. Thus, depression of cell-mediated immunity during the acute phase of herpes zoster was associated with a relative increase of lymphocytes expressing a suppressor cell phenotype and the activation of a radiosensitive Leu-2+ suppressor cell with some degree of antigen specificity.  相似文献   

7.
On the control between cell-mediated, IgM and IgG immunity   总被引:6,自引:0,他引:6  
An hypothesis is proposed here describing some of the conditions that determine the type of response an antigen will induce, and explaining how the induction of one type of immunity affects the induction of other types of immunity. In more detail, the hypothesis attempts to account for the following observations: Some antigens induce only cell-mediated immunity, whereas others can, under different conditions, induce either cell-mediated or humoral immunity. The humoral response to most antigens consists of an initial period of IgM antibody synthesis, followed by a period of IgG synthesis. Some polymeric antigens induce the synthesis of only IgM antibody. There is a tendency for the immune response to an antigen, at a particular time, to be exclusively of the cell-mediated, IgM or IgG type.The hypothesis may also be relevant to some observations that, I believe, have been incorrectly interpreted to mean that “tolerance” to some antigens requires the presence of T (thymus-derived) cells specific for these antigens. The hypothesis suggests teleological reasons for the existence of the different types of immunity. It also suggests ways of controlling the type of response an antigen induces.  相似文献   

8.
Cell-mediated immunity to antigens prepared from both serum and liver of patients positive for hepatitis-associated antigen (H.A.A.) was measured by using the leucocyte migration test. Altogether, 43 patients with H.A.A.-positive acute and chronic liver disease, eight with serum antibody to H.A.A., and 13 controls were studied. The cell-mediated immunity detected was specific for H.A.A. or other antigenic determinants of the associated infective agent and could be found only in patients with evidence of previous contact with H.A.A.Cell-mediated immunity to the H.A.A.-positive test antigens was found in all but one of the patients with acute hepatitis, in about half of the patients with chronic aggressive hepatitis or cirrhosis, rarely in those with chronic persistent hepatitis, and in none of the apparently healthy carriers.Our results support the hypothesis that the cellular immune response plays an important part in the clearance of the infective agent from H.A.A.-positive patients and in the pathogenesis of the associated liver cell injury.  相似文献   

9.
Mycobacterium abscessus has been identified as an emerging pulmonary pathogen in humans. Because little is known regarding immune responses elicited by M. abscessus or its antigens, immunological responses were studied in two murine models subjected to intravenous (high-dose or systemic infection) or pulmonary (low-dose or local infection) inoculation with M. abscessus ATCC 19977. An overall comparison between the two models showed similar patterns of bacterial survival and host immune responses. The colonization of M. abscessus was the highest at 5 days post-infection (dpi) and its elimination was positively correlated with cell-mediated immunity in both challenges. However, an inverse relationship was observed between progressive inflammation and mycobacterial colonization levels in mice infected with a high dose at 14 dpi. Regarding antigens, culture filtrate (CF) of M. abscessus strongly induced IFN-γ secretion, whereas cellular extract (CE) antigen elicited strong antibody responses. The antibody response to M. abscessus antigens in mice subjected to low-dose infection increased when the cellular immune response decreased over 14 dpi. However, the antibody response for the high-dose infection increased promptly after the infection. In comparison of cytokine expression in lung homogenates after M. abscessus infection, Thl and Th2 cytokines increased simultaneously in the high-dose infection, whereas only cell-mediated immunity developed in the low-dose pulmonary infection. These findings not only enhance our understanding of the immune response to M. abscessus infection according to systemic or pulmonary infection, but may also aid in immunological diagnosis and vaccine development. M. abscessus, murine infection model, immune response, antigens, cytokines  相似文献   

10.
The immunizing abilities of alloantigens placed within the anterior chamber of the eye have been studied in inbred rats. Although intracameral inoculation of F1 hybrid lymphocytes into parental strain recipients elicited both cell- and antibody-mediated immunity, a delimited interval was identified postinoculation during which the systemic cell-mediated immune response was suppressed as indicated by prolonged acceptance of orthotopic skin allografts. The prompt appearance of hemagglutinating antibodies in the serum of immunized rats followed a time course which coincided with the suppression of cell-mediated immunity and suggested that the two events are casually related. Since exposure to allogeneic antigens on lymphoid cells via the anterior chamber elicits a transient suppression in cell-mediated immunity, where humoral immunity is preserved, the phenomenon resembles immune deviation.  相似文献   

11.
T-lymphocyte immune capacity in man was assessed semiquantitatively by two in vivo procedures: the primary type of response to dinitrochlorobenzene and the secondary type of response, representing memory, to a group of five uniquitous antigens. Controlling for degree of illness proved important in assessing immune capacity in specific diseases; thus, the number of responders and mean score of semiquantitated responses was significantly lower in groups of patients with cancer and multisystem autoimmune disease when comparisons were made with healthy persons, but less so when comparisons were made with a group of subjects with other incapacitating diseases. A notable finding was the lack of correlation in the results of tests of cell-mediated immunity between the two procedures described. Depressed cell-mediated immunity shown in multisystem autoimmune disease is relevant to both predisposition to infection and the postulated role of thymic dysfunction in the pathogenesis of autoimmunity.  相似文献   

12.
H-2 dependency of T cell-mediated cytotoxicity and transplantation immunity to leukemia-associated antigens has been investigated. Through the use of a 20-hr 125IUdR release assay, it was found that the induction of T cell-mediated cytotoxicity against Friend virus-induced leukemias of different H-2 haplotype orgins could be produced by immunization with both syngeneic and allogeneic tumor cells; the effector cells that were generated by syngeneic immunization could also provide effective killing of allogeneic tumor cells, although the killing of allogeneic targets might require a longer incubation time (20 to 40 hr). Furthermore, in vivo transplantation immunity against Friend virus-induced leukemias also was induced by immunization with both syngeneic and allogeneic tumors and syngeneic immunization could induce specific protection against the challenge with a-logeneic tumor in x-irradiated hosts. These findings clearly indicate that, both at the sensitizing phase and effector phase of the immune response, there is no strict H-2 dependency for T cell-mediated cytotoxicity or in in vivo transplantation imunity to leukemia-associated antigens.  相似文献   

13.
The agarose-droplet cell-migration-inhibition assay was developed for measuring specific cell-mediated immunity in rats. Fischer #344 female rats were sensitized to mono(p-azobenzene-arsonate)-N-chloroacetyl-L-tyrosine (ARSNAT), keyhole-limpet-hemocyanin (KLH), or a BCG cell wall preparation. The optimal conditions for assay were determined by testing varying concentrations of antigens against normal and sensitized peritoneal exudate cells induced with 5% thioglycolate medium. Specific cell-mediated immunity to each of three different antigens was detected, which correlated with skin tests observed in vivo. Our adaptation of the agarose-droplet assay should provide a useful model for studying other aspects of cell-mediated and/or tumor immunity in the rat.  相似文献   

14.
Study showed that five (C3, C6, C9, C10, C11) out of ten chromatographic fractions of surface and capsular antigens of B. mallei significantly stimulated cell-mediated immunity that manifested in activation of delayed hypersensivity reactions (DHS) and phagocyteability of noncapsulated avirulent strain of B. mallei with added surface and capsular antigenic complexes. Other fractions did not stimulate cell-mediated immunity, furthermore, fraction C8, which contained capsular biopolymer with mass of 200 kD (Ar8), was characterized by immunosuppressive effect on DHS and phagocytosis. Observed stimulation of cell-mediated immunity by fractions referred above has been confirmed by assessment of their protective effects on the model of experimental melioidosis in white rats. Relationship between markers of humoral and cell-mediated immunity, including markers of specific response, was not observed.  相似文献   

15.
Infection with Herpesvirus hominis, often associated with oral ulceration, was found to be more frequent in patients with myeloproliferative and lymphoproliferative disorders than in normal populations or patients with other diseases. This increased frequency was not associated with any deficiency of the humoral antibody response, suggesting a possible impairment of cell-mediated immunity. The otherwise untreatable oral lesions appeared to respond effectively to local irradiation.  相似文献   

16.
Pathophysiology of Chagas' disease is not completely defined, although innate and adaptative immune responses are crucial. In acute infection some parasite antigens can activate macrophages, and this may result in pro-inflammatory cytokine production, nitric oxide synthesis, and consequent control of parasitemia and mortality. Cell-mediated immunity in Trypanosoma cruzi infection is also modulated by cytokines, but in addition to parasite-specific responses, autoimmunity can be also triggered. Importantly, cytokines may also play a role in the cell-mediated immunity of infected subjects. Finally, leukocyte influx towards target tissues is regulated by cytokines, chemokines, and extracellular matrix components which may represent potential therapeutic targets in infected patients. Here we will discuss recent findings on the role of cytokines, chemokines and extracellular matrix components in the regulation of innate and adaptive immunity during T. cruzi infection.  相似文献   

17.
Pulmonary granulomas were induced in BALB/c mice immunized with methylated bovine serum albumin in complete Freund's adjuvant by the intratracheal injection of plain agarose beads or beads conjugated to specific antigen. Large hypersensitivity granulomas developed around antigen-coupled beads in immunized animals. Smaller but still prominent granulomatous reactions developed around plain beads in immunized mice. In nonimmunized animals, both plain and antigen conjugated beads produced very small granulomas. Granuloma formation in sensitized animals was associated with suppressed delayed-type hypersensitivity reactions induced by the footpad injection of specific and nonspecific antigens. Lymph node cells from sensitized granuloma-bearing mice with cutaneous anergy showed suppressed specific and nonspecific antigen-induced proliferative responses in vitro. These cells also showed suppressed interleukin 2 production in response to specific antigen. Although no soluble suppressive factor was detected in granuloma extracts, suppressor cells were found in lymph nodes of granuloma-bearing mice, which could inhibit antigen-induced production of interleukin 2 by lymph node cells from immunized mice. Antigen-specific immunoglobulin G antibody production was not suppressed in immunized granuloma-bearing mice. Previous studies from our laboratory have demonstrated migration inhibition factor and interleukin 1 activities in aqueous extracts prepared from granuloma-bearing lungs of immunized mice. These results and the findings reported here indicate that granuloma formation and the associated anergy observed in this system are primarily expressions of cell-mediated immunity; selective suppression of in vivo and in vitro expressions of cell-mediated immunity in granuloma-bearing mice may be due to impaired antigen-induced interleukin 2 production; and such impairment is caused by suppressor cells.  相似文献   

18.
BALB/c mice can be protected against a fatal Leishmania major infection by immunization with whole radio-attenuated promastigotes; however, neither the antigens responsible for protection nor the protective immunologic mechanisms have been defined. In this study, the ability of promastigote fractions to elicit similar immunity to that obtained with whole organisms, and the immune responses associated with such protection were analyzed. Intraperitoneal immunization with a soluble, membrane-free parasite extract was found to induce protection against L. major challenge equal to that obtained with whole organisms. Induction of immunity (89% protection in seven experiments) was most effective with 100 micrograms of the soluble leishmanial antigen (SLA) and required concomitant injection of the bacterial adjuvant, Corynebacterium parvum (CP), followed by an i.p. boost of SLA alone 1 wk later. Vaccinated animals exhibited Leishmania-specific cell-mediated immunity, as assessed both by lymphocyte transformation and the production of macrophage-activating factors (MAF). In addition, although SLA + CP-immunized mice failed to exhibit delayed-type hypersensitivity (DTH) before challenge, splenic lymphocytes from these mice could transfer a local DTH reaction to naive recipients. Immunization also induced the production of antibodies against two major metabolically labeled proteins of m.w. 30,000 and 53,000, but failed to stimulate a detectable humoral response against promastigote surface antigens. Thus, these experiments demonstrate that vaccine-induced immunity against cutaneous leishmaniasis is strongly associated with the induction of cell-mediated immunity, but does not require the development of an antibody response to promastigote surface antigens. In addition, these studies establish the feasibility of employing soluble, nonmembrane-derived parasite material as a source of protective immunogens.  相似文献   

19.
The adoptive transfer of cytotoxic T lymphocytes (CTLs) derived from tumor-infiltrating lymphocytes (TIL) along with interleukin 2 (IL-2) into autologous patients with cancer resulted in the objective regression of tumor, indicating that these CTLs recognized cancer rejection antigens on tumor cells. To understand the molecular basis of T cell-mediated antitumor immunity, several groups started to search for such tumor antigens in melanoma as well as in other types of cancers. This led to the subject I will review in this article. A number of tumor antigens were isolated by the use of cDNA expression systems and biochemical approaches. These tumor antigens could be classified into several categories: tissue-specific differentiation antigens, tumor-specific shared antigens, and tumor-specific unique antigens. However, the majority of tumor antigens identified to date are nonmutated, self proteins. This raises important questions regarding the mechanism of antitumor activity and autoimmune disease. The identification of human tumor rejection antigens provides new opportunities for the development of therapeutic strategies against cancer. This review will summarize the current status and progress toward identifying human tumor antigens and their potential applications to cancer treatment.  相似文献   

20.
The immune status of children with malignant disease in remission was assessed usingvarious immune function tests. Children with infections had significantlymore neutropenia, hypogammaglobulinaemia, and impaired cell-mediated immune responses than those without. These two groups combined had much more absolute lymphopenia and impairment of both cell-mediated immunity and antibody-producing capacity thancontrol children with non-malignant conditions. Regular immunological evaluation isrecommended for children with malignant disease when new intensive treatment schedules are under trial and for individual patients particularly prone to develop infections during treatment.  相似文献   

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