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1.
The present studies were designed to evaluate possible efficacy of specific human transfer factor (TF) in preventing or attenuating varicella-zoster (VZ) infection in children with acute lymphocytic leukemia (ALL). TF was prepared following leukapheresis of adult donors who were convalescing from chicken pox. Recipients were VZ seronegative children with ALL, 12 in remission and 3 in relapse; a single injection of TF was given equivalent to 108 lymphocytes per 7 kg body wt. The following VZ-specific parameters were measured: lymphocyte blastogenesis, cytotoxicity and leukocyte inhibitory factor (LIF) production, and indirect fluorescent and CF antibody titers. No patients in relapse converted immune response while 1012 in remission developed positive reactivity in at least one assay of cell-mediated immunity (CMI); 312 were positive in all three parameters of CMI and 812 in two assays. Cytotoxicity was the most consistently positive test following TF administration. No patients developed VZ antibody. Seventeen months follow-up has demonstrated persistent cellular immunity.  相似文献   

2.
The CMI response in vitro and in vivo of 30 patients with a poor biologic response to infection with C. immitis was investigated. In patients with active pulmonary disease, skin reactivity to CDN was observed in 710, and to at least one of five other antigens in 810. In patients with the most extensive infection, disseminated disease, skin reactivity to CDN and to at least one of five other antigens was observed in only 48. In patients with inactive disease, skin reactivity to CDN and to at least one of five other antigens was observed in 1112. Even when skin reactivity to CDN was present, MIF release and, more frequently, 3H-thymidine incorporation were not consistently stimulated by CDN. Maximal 3H-thymidine incorporation in response to PHA and CDN is delayed in 50% of the patients studied. The defect also may be present in patients with inactive disease; however, in two patients followed serially, lymphocyte function very slowly returned to normal. Rosette-forming cells were normal in 1830.The frequency with which patients with coccidioidal disease demonstrate a defect in cell-mediated immunity raises unanswered questions about the mechanisms responsible for the defect and the role it may play in the biologic defense against invasion by this fungus.  相似文献   

3.
The immune response of WFu rats to a syngeneic Gross virus-induced lymphoma (C58NT)D evokes the simultaneous generation of effector cells able specifically to destroy the tumor cells by two different cytotoxic pathways: cell-mediated cytotoxicity (CMC) and antibody-dependent cellular cytotoxicity (ADCC). The question of possible interdependence in the relationship between the effector cells mediating both cytotoxicities was approached in several ways: (a) Immunospecific competition of one form of cytotoxicity (CMC or ADCC) did not interfere with the full expression of the other cytotoxic effect (ADCC or CMC, respectively), (b) Elimination of T cells by anti-thymocyte serum and complement completely abrogated the CMC activity while not impairing the ADCC activity, (c) Specific depletion of cytotoxic (CMC) lymphoid cells on monolayers of target cells bearing the sensitizing antigens considerably diminished the CMC activity, but did not affect the ADCC activity, (d) Depletion of Fc receptor-bearing cells (non-T cells) markedly reduced the ADCC activity, but did not interfere with CMC activity. These findings indicate that, in this system, two forms of cell-mediated cytotoxicity to tumor-associated antigens exist concurrently in the immune host and are expressions of different lymphoid cell populations; CMC is mediated by T cells, whereas ADCC is a non-T cell function.  相似文献   

4.
The cytotoxic potential of rabbit peripheral blood monocytes and alveolar macrophages in antibody-dependent cellular cytotoxicity (ADCC) toward both erythrocyte (RBCox) and tumor cell (CEM T-lymphoblast) targets was examined. ADCC was measured in a 4-hr 51Cr-release assay. Alveolar macrophages were more efficient at killing the tumor cell targets (optimally sensitized with rabbit antisera) than monocytes at similar effector cell/target cell (ET) ratios. Tumor cell targets sensitized with seven different antisera (anti-CEM) were lysed by alveolar macrophages but not by the monocytes. In marked contrast, the monocytes were more effective at lysing the sensitized erythrocyte target cells. The degree of cytolysis of RBCox and CEM was dependent on the ET ratio and the degree of sensitization of these target cells. It was demonstrated that the effector cell selectivity in ADCC was directly related to their ability or inability to bind the sensitized target cells as determined by Fc-receptor rosette formation. The transition from monocyte to macrophage may, therefore, have resulted in an alteration in the criteria necessary for Fc-receptor binding to antibody-sensitized target cells and subsequent ADCC.  相似文献   

5.
In a previous publication it was reported that a polysaccharide-protein complex (PPC), sensitive to -glucosidase, was isolated from Histoplasma capsulatum. This complex was strongly reactive in an agar gel diffusion assay with sera from patients with histoplasmosis, but was unreactive with sera from patients with coccidioidomycosis. Here, the studies with human sera have been expanded and attempts were made to determine the response of mice immunized with nonviable H. capsulatum or Cocccidioides immitis to PPC or its deproteinized fraction (D-PPC) using more sensitive tests for antibody and including also test for cell-mediated immunity. Histoplasmin and coccidioidin were compared with PPC or its deproteinized fraction (D-PPC) in all assays. In a counterimmunoelectrophoresis (CIE) assay, PPC and D-PPC reacted only with sera from patients with histoplasmosis, whereas cross reactions were noted with histoplasmin and coccidioidin using heterologous sera. Cross-reaction were observed with all four antigen preparations and both types of antisera using a micro complement fixation assay. The assay for macrophage migration inhibitory factor (MIF) was also relatively nonspecific, in that inhibition occurred with cells from animals sensitized with Histoplasma or Coccidioides using both homologous and heterologous antigens. In the footpad assay, histoplasmin and coccidioidin were highly cross-reactive in animals sensitized with the heterologous fungus, but the PPC and D-PPC from H. capsulatum elicited significant reactions only in animals sensitized with Histoplasma.  相似文献   

6.
Transfer of cell-mediated immunity was achieved with dialyzable cell-free extracts from lymphoid cells of mice primed to the contact sensitizing agent, 2,4-dinitrofluorobenzene (DNFB). The biological activity of the extract (Transfer Factor, TF) was analyzed in vivo by the ear thickness assay and in vitro by the macrophage migration inhibition (MMI) test and lymphocyte transformation using the soluble analog, sodium 2,4-dinitrobenzenesulfonate. Consistently positive responses occurred 20 hr following a single intravenous injection of 5 × 107 lymphocyte equivalents per recipient. The most potent source of TF (memory TF) was lymph node cells obtained 30 days after primary exposure to DNFB. By contrast TF prepared at the peak of the response to DNFB was less potent which was shown to be due to the presence in it of a suppressor factor. Memory TF elicited macrophage inhibition factor production in naive lymph node cells whereas positive responses were only obtained in the ear thickness and lymphocyte transformation assays provided recipients had undergone prior subliminal sensitization. Specificity of TF was tested using picryl chloride and oxazolone as control antigens. Results from the MMI and ear thickness assays were consistent with the presence in Transfer Factor of an antigen-specific component. Its effects, however, on the proliferative response to antigen lacked specificity and depended on prior sensitization of recipients, rather than donors, to the inducing antigen. The target of the specific component was considered to be an Ly-1+, Ia?, Ly23? T cell since MIF production and in vivo delayed hypersensitivity are known to be mediated by a T cell bearing this phenotype. Taken together these findings emphasize the value of using a battery of tests of cell-mediated immune function when studying soluble mediators such as Transfer Factor and suggest that the current system is a valid experimental model for analysis of the Transfer Factor phenomenon.  相似文献   

7.
Collagen sponges, labelled with fluorescein, were implanted under the back skin of sensitized rats. These elicited an acute inflammatory reaction with cellular invasion of the sponge and the development of a fibrous capsule at the periphery. After 4 days each sponge, together with the fibrous capsule, was excised and placed into tissue culture. Degradation of the collagen sponge by the invading cells was monitored from the release of soluble fluorescein peptides into the medium. The addition of foetal calf serum caused inhibition above 5% (v/v). Inhibitors of collagenase and neutral proteinases blocked the release of fluorescein peptides. Collagenolysis was also abolished or retarded by inhibitors of lysosomal cathepsins. The anti-inflammatory drug, dexamethasone, blocked all collagenolytic activity whereas indomethacin was without effect. The exvivo model offers the possibility for following the activity of the invading phagocytic cells and for examining the enzymatic mechanisms involved in collagenolysis using appropriate perturbation techniques.  相似文献   

8.
Cellular immunity has been studied in mice at various times during the induction of amyloidosis following multiple injections of casein. The assay system used was one which measured delayed hypersensitivity (DH) in vivo, by injecting antigen into the left ear lobe of sensitized mice, followed by the intravenous administration of 125I-deoxyuridine (125I-UdR). The ears were then cut off and the LR125I-UdR ratio provided a measure of DH. It was found that DH to casein appeared in pre-amyloidotic mice, remained through the stages of mild and moderate amyloidosis and disappeared in severely amyloidotic mice. DH to fowl IgG disappeared after three injections of casein and remained absent at all times thereafter, likely due to antigenic competition. In contrast, DH to DNFB persisted at all times, even in the face of severe amyloidosis. These results have been interpreted to indicate that, using this assay, DH is normal during casein-induced murine amyloidosis.  相似文献   

9.
Bone marrow cells from methenolone acetate injected normal or hypertransfused polycythemic rats were cultured with erythropoietin. Heme synthesis rate in these cells was apparently increased as compared to control bone marrow cells similarly cultured. Plasma erythropoietin activity of methenolone treated rats was not detectable either by in vivo nor by in vitro assay methods. It was suggested that methenolone stimulates erythropoiesis by increasing the number and/or sensitivity of erythropoietin responsive cells.  相似文献   

10.
Immunologic tolerance to hepatitis B antigen, evidenced by a lack of specific cellular and humoral immune response to HBsAg, produces a chronic carrier state which serves as an epidemiologic reservoir for the transmission of viral hepatitis type B. It is proposed that cell-mediated immunity transferred with immune-RNA may serve to terminate immunologic tolerance to hepatitis B antigen and abolish the carrier state. The efficacy and safety of ‘immune-RNA’ administration to chronic carriers can be validated by leukocyte migration inhibition techniques in vitro and in HBsAg positive chimpanzees in vivo.  相似文献   

11.
Inbred C57B16 and CBA mice were immunized with 60Co-irradiated (50 kR) Schistosoma mansoni cercariae. Based on the percentage reduction from controls in the numbers of adult parasites developing from a challenge cercarial exposure, the level of protection among immunized C57B16 mice ranged from 56 to 74%, and among immunized CBA mice from 10 to 27%. In a longitudinal study, parallel in vitro comparisons of mitogen- and antigen-stimulated lymphocyte proliferative responses were performed with spleen cells from immunized and control mice of both strains. In contrast to decreased mitogen reactivity during a chronic, patent infection, immunization with irradiated cercariae resulted in no alteration in PHA and LPS responses in the reactivity of either strain. A vigorous antigen-specific reactivity was noted in the responses of immunized CBA mice. Additionally, a biphasic pattern of responsiveness characterized the CBA responses to antigens of cercarial, adult worm, or schistosomal egg origin. In comparison, there was a greatly diminished reactivity in immunized C57B16 mice to the same antigens. Therefore, no obvious correlation existed in this model between the relative magnitude of antigen-specific responses between the two strains and the level of anti-schistosome immunity induced.  相似文献   

12.
《Life sciences》1996,59(18):1499-1506
A wide variation in the performance of inbred rats measured in the elevated plus maze test suggests a possible genetic basis for anxiety response (AR). To gain further insight into the role of genetics in AR, we have characterized AR in male outbred S-D rats. Rats were placed in the black compartment (BC) facing the wall opposite the aperture and time needed for the animal to exit BC was noted. All rats underwent 3 successive trials 1–1.5 hrs apart. Naive rats showed a wide variation in their AR in trial 1(mean = 89 ± 19 sec, range = 5–360 sec). Sixty-eight % of the rats exhibiting low AR exited BC in <30sec, whereas 16% stayed in for the entire 360 sec (high AR). On successive testing, there was a progressive increase in AR which reached to max on second trial (Trial 1: 89±19, Trial 2: 171± 23, Trial 3: 210± 22 sec, p<0.0001). The time spent in BC on successive trials increased for most rats (3344), decreased for some (244), showed min to no change (544) or erratic response (444) for others. In conclusion wide variation in the AR in outbred rats could be exploited to study genetic and neurochemical mechanisms of anxiety.  相似文献   

13.
Glutathione S-transferase activity was determined in rat, rabbit, and guinea pig serum using styrene 7,8-oxide (SO) and benzo (a) pyrene 4,5-oxide (4,5-BPO) as substrates. Of the species tested, rat had the highest transferase activity (62.5 and 3.2 nmol/min/ml serum for SO and 4,5-BPO, respectively) and rabbit had the lowest activity. Glutathione S-transferase activity was 60% higher in serum from male rats than in female rats. In rats, serum enzyme specific activities (nmol/min/mg protein) were less than 1% of hepatic enzyme activities with SO, 4,5-BPO, 1,2-dichloro-4-nitrobenzene (DCNB), and 1-chloro-2,4-dinitrobenzene (DNCB). Glutathione S-transferase activity was also determined in rat serum during perinatal development. Serum from rats at 18 days of gestation or from 1- and 4-day-old animals had barely detectable transferase activity. Activity increased with age and reached a maximum in 140-day-old animals. The intraperitoneal administration of diethyl maleate (DEM) (0.8 ml/kg) or L-methionine-DL-sulfoximine (MS) (200 mg/kg) to male rats had no effect on serum or hepatic glutathione S-transferase activities 2 or 26 hr after dosing. Treatment with carbon tetrachloride (CCl4) (1 m1/kg) caused an 11-fold increase in serum transferase activity and a 40% decrease in liver specific activities 24 hr after administration.  相似文献   

14.
I/i antigens on the membrane of peripheral blood lymphocytes (PBL) in Graves disease were investigated by bithermic 2-hr cytotoxicity assay using homogeneous anti-i and anti-I cold agglutinins (CA). Cytotoxicity curves using dilutions of CA from 1100 to 11200 and 50% cytotoxicity titers were assessed in 20 patients with Graves disease and 22 matched controls. No statistically significant differences were observed in cytotoxicity curves up to the highest dilution, whereas estimation of the 50% cytotoxic titers showed that PBL in Graves disease were slightly more susceptible to anti-I CA as compared to normal PBL. Thus, the statement of Farid et al. (Cell. Immunol.22, 394, 1976) that PBL in Graves disease are less susceptible to cold agglutinins and that their I/i antigens are masked by autoantibodies cannot be confirmed.  相似文献   

15.
The present study was carried out in order to assess the time course of action of progesterone (P) in the facilitation of complete feminine sexual behavior. Female rats (estrogen primed via 5% E2 Silastic capsules) were given 200 μg of P either intravenously (iv) or subcutaneously (sc), and tested for estrous behavior at 14, 12, 1, 2, and 4 hr after treatment. Among iv-treated animals, significant amounts of lordosis behavior were seen as early as 12 hr, and a dramatic rise in solicitation behavior was observed at 2 hr. Although sc-treated animals displayed significant amounts of lordosis and solicitation behavior at 2 hr, the behavior was not maximal until 4 hr. Intravenous administration of 400 μg P was equipotent to 200 μg P, whereas 50 μg of iv P was relatively ineffective. A dual mechanism hypothesis pertaining to progesterone's actions in the facilitation of both the receptive and preceptive components of feminine sexual behavior in rats is discussed.  相似文献   

16.
To determine the possible physiologic contribution of GABA to the tonic hypothalamic inhibition of adenohypophyseal prolactin secretion, we compared GABA levels in hypophyseal stalk plasma with those found in the peripheral circulation. Hypophyseal stalk blood was collected via a parapharyngeal approach from 8 urethane anesthetized diestrus rats. Peripheral blood was collected simultaneously from the external jugular vein of the same rat at a rate similar to hypophyseal stalk blood flow. Blood samples resulting from a single 4 hr collection per animal were centrifuged, and the plasma stored frozen before ethanol extraction and assay using a radioreceptor method. GABA levels in hypophyseal stalk plasma (909±171 pmol/ml; X ± S.E.M.) were not significantly higher than levels in peripheral plasma (845±182; p>0.05), indicating little or no secretion of GABA by the median eminence.  相似文献   

17.
Using steady-state relaxation spectrophotometric technique a P700 component (t 12 ~20 ms) has been detected which was sensitized by low concentration (10?7M) DCMU in isolated broken chloroplasts of pea. The relative quantum yield of electron flux through DCMU-sensitized P700 was similar to that with methyl viologen or NADP as terminal electron acceptor and water as electron donor. Kinetic analysis showed that a small fraction (10%) of the total P700 reaction centers was sensitized by low DCMU.  相似文献   

18.
Groups of adult male rats treated with 3-methylcholanthrene, phenobarbital or vehicles alone, were administered caffeine either orally or intravenously. Serum caffeine concentrations were measured by radioimmunoassay. In vehicle and phenobarbital pretreated animals, caffeine elimination kinetics were non-linear. In control animals, the invivo apparent Km was 8 μg·ml?1 (40 μM) and the apparent Vmax was 0.1 μg·ml?1·min?1 (0.5 μM·min?1). Phenobarbital pretreatment did not change the apparent Km but slightly increased the apparent Vmax. 3-Methylcholanthrene pretreatment dramatically altered the elimination kinetics of caffeine, whether caffeine was given orally or intravenously. The elimination of caffeine from serum of 3-methylcholanthrene pretreated rats was first order with a t12 of approximately 14 minutes.Our results are consistent with the proposed involvement of the cytochromes P-450 monooxygenase system in the elimination of caffeine. In addition, our results suggest that caffeine is a moderately poor substrate for the cytochromes P-450 present in control and phenobarbital-pretreated rats, but a particularly good substrate for the form(s) induced by 3-methylcholanthrene.  相似文献   

19.
Biomphalaria glabrata snails sensitized by exposure to X-irradiated miracidia of the trematode, Ribeiroia marini, acquired resistance to challenge with nonirradiated R. marini miracidia. Resistance was acquired within 1 day of sensitization; was strongest at 1 week, when infection rates of sensitized snails were 15% of the controls (i.e., SC = 0.15); and persisted for at least 3 weeks. By 30 days the difference between the infection rates of sensitized and control snails was no longer statistically significant. As in previous studies with echinostomes, acquired resistance to R. marini was characterized histologically by the destruction of irradiated sporocysts by host amoebocytes. Following destruction of all irradiated sporocysts, snails became resistant and encapsulated and destroyed nonirradiated challenge sporocysts within 1 day postchallenge. Associated with sporocyst destruction was an enlargement of the amoebocyte-producing organ, which showed intense mitotic activity. A proportion of the nonirradiated challenge sporocysts were also destroyed in most nonsensitized control snails, which consequently had a temporarily enlarged amoebocyte-producing organ. In contrast to acquired resistance reported to echinotomes, which is quite specific, acquired resistance to R. marini was associated with nonsusceptibility to both Echinostoma paraensei (SC = 0.19) and Schistosoma mansoni (SC = 0.81).  相似文献   

20.
Three-day old rats were injected subcutaneously either with natural purified pig ACTH (ACTH 1–39), ACTH 1–24, or ACTH analogues as long-acting zinc-phosphate preparations. ACTH 1–39, ACTH 1–24, ACTH 1–18, ACTH 1–16 accelerated the time of eye-opening, whereas an extract of corticosteroids produced invitro by excised adrenals of ACTH-treated three-day old rats was ineffective. Injections with ACTH on the twelfth day of life had no effect on eye-opening. It is concluded that a neonatal injection with ACTH or closely related analogues with markedly less corticotropic activity can accelerate the time of eye-opening. This effect is not mediated by the adrenal cortex. The sensitive period for it appears to be shortly after birth.  相似文献   

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