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1.
A monkey-adapted strain of Plasmodium vivax (Achiote) was transferred by trophozoites through 11 serial passages in Saguinus geoffroyi (Titi marmoset). Patent infections developed in both normal (23 of 24) and splenectomized (8 of 9) marmosets. The infections in the altered animals were of greater severity than in the intact subjects as indicated by patent periods (x? = 87 vs 61 days) and maximum parasitemias (x? = 35,018 vs 16,218 per mm3).Relapses were recorded in 13 of 14 unaltered and 4 of 4 splenectomized animals that survived the primary attack. As evidence for acquired immunity, the mean maximum parasitemias during relapse in the normal animals were 18 of the values during the primary attack; patent periods were shorter than those in the initial infection. There was also some indication of an acquired immunity in the splenectomized group of animals. However, one splenectomized marmoset experienced a patent period of 325 days during the first relapse.There was considerable variation of infection parameters among the animals in each group.  相似文献   

2.
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   

3.
Normal estrous cycles were established for twenty beef heifers. Ten heifers were inoculated with blood from a known Anaplasmamarginale carrier. The inoculated heifers experienced anemia, anorexia, and positive Anaplasmamarginale complement-fixing antibody titers, and A. marginale was observed on the erythrocytes while uninoculated control heifers remained normal. Further observation following inoculation revealed that five of ten inoculated heifers experienced anestrus while controls continued to cycle normally. Anestrus coincided with clinical signs of acute anaplasmosis. Normal estrus patterns returned following treatment and recovery. This study provides evidence that acute anaplasmosis in beef heifers may cause anestrus and therefore lead to reproductive inefficiency.  相似文献   

4.
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   

5.
Although children with acute lymphoblastic leukemia (ALL) generally have a good outcome, some patients do relapse and survival following relapse is poor. Altered DNA methylation is highly prevalent in ALL and raises the possibility that DNA methylation-based biomarkers could predict patient outcome. In this study, genome-wide methylation analysis, using the Illumina Infinium HumanMethylation450 BeadChip platform, was carried out on 52 diagnostic patient samples from 4 genetic subtypes [ETV6-RUNX1, high hyperdiploidy (HeH), TCF3-PBX1 and dic(9;20)(p11–13;q11)] in a 1:1 case-control design with patients who went on to relapse (as cases) and patients achieving long-term remission (as controls). Pyrosequencing assays for selected loci were used to confirm the array-generated data. Non-negative matrix factorization consensus clustering readily clustered samples according to genetic subgroups and gene enrichment pathway analysis suggested that this is in part driven by epigenetic disruption of subtype specific signaling pathways. Multiple bioinformatics approaches (including bump hunting and individual locus analysis) were used to identify CpG sites or regions associated with outcome. However, no associations with relapse were identified. Our data revealed that ETV6-RUNX1 and dic(9;20) subtypes were mostly associated with hypermethylation; conversely, TCF3-PBX1 and HeH were associated with hypomethylation. We observed significant enrichment of the neuroactive ligand-receptor interaction pathway in TCF3-PBX1 as well as an enrichment of genes involved in immunity and infection pathways in ETV6-RUNX1 subtype. Taken together, our results suggest that altered DNA methylation may have differential impacts in distinct ALL genetic subtypes.  相似文献   

6.
Anti-allotype b4 and anti-allotype a3 antibody as well as heterologous anti-rabbit IgG enhanced the lymphocyte-dependent antibody cytotoxicity, in a system using chicken red blood cells (ChRBC) coated with rabbit anti-ChRBC antibody (a3a3, b4b5) as target cells and rabbit lymphocytes (a3a3, b4b5). No enhancement was observed with anti-allotype b6 antiserum, nor with heterologous anti-rabbit IgM, IgA, and Fc antibodies. Cytotoxicity mediated by spleen, bone marrow, and thymus lymphocytes was enhanced by anti-allotype antibody. The enhancement of cytotoxicity by anti-allotype antibody cannot be attributed to lymphocyte proliferation but is more likely related to the formation of an additional bridge between effector cell and target cell.  相似文献   

7.
In this study, the cells producing T-cell growth factor (TCGF) in the rat MLR were characterised with respect to the antigens defined by W313, W325, and OX8 monoclonal antibodies. Unfractionated lymphocytes and cells depleted of OX8 positive cells were found to be fully capable of producing TCGF, whereas lymphocytes depleted of W313andW325 positive cells had lost this ability. Parallel experiments demonstrated that cells selected by the fluorescence-activated cell sorter for the expression of W313andW325 defined antigens were potent producers of TCGF. Further studies suggested a functional role for the antigen defined by W325 antibody because the addition of this antibody to a MLR abrogates TCGF production. These findings suggest that the important immunomodulatory functions of W325 positive lymphocytes could be exercised via the synthesis of essential lymphokines.  相似文献   

8.
Results of conventional treatment of female non-bacterial recurrent cystitis (NBRC) are discouraging. Most patients show an unexpected high incidence of vaginal candidiasis, while their cell mediated immunity to Herpes simplex viruses (HSV) and Candida antigens seems impaired, and it is known that the persistence of mucocutaneous chronic candidiasis is mainly due to a selective defect of CMI to Canadida antigens. Twenty nine women suffering of NBRC, and in whom previous treatment with antibiotics and non-steroid anti-inflammatory drugs was unsuccessful, underwent oral transfer factor (TF) therapy. TF specific to Canadida and/or to HSV was administered bi-weekly for the first 2 weeks, and then once a week for the following 6 months. No side effects were observed during treatment. The total observation period of our cohort was 24379 days with 353 episodes of cystitis recorded and a cumulative relapse index (RI) of 43. The observation period during and after treatment was 13920 days with 108 relapses and a cumulative RI of 23 (P < 0.0001). It, thus, seems that specific TF may be capable of controlling NBRC and alleviate the symptoms.  相似文献   

9.
The outcome after bone-marrow relapse was assessed in 53 children with acute lymphoblastic leukaemia (ALL). Twenty-five out of 37 children (67%) whose first remission ended in relapse during treatment (group A) achieved a second remission, as did 15 out of 16 (94%) who relapsed after treatment had been stopped (group B). Nevertheless, the median duration of second remission was only 12 weeks in group A and 35 weeks in group B. The median survival from time of relapse was 32 weeks in group A and 75 weeks in group B. It is concluded that marrow relapse is equally serious whether it occurs during treatment or after treatment has been stopped, and that most children with ALL have a single chance of cure at the time of diagnosis.  相似文献   

10.
Transfer factor (TF) causes nonimmune lymphocytes to produce leukocyte migration inhibitory factor (LMIF) in the presence of purified protein derivative (PPD). The activity of TF was measured by leukocyte migration inhibitory test (LMIT). The LMIT was a modification of the conventional agarose droplet method. To express the activity of LMIF quantitatively and simply, LMIF titer was introduced. The LMIF titer was obtained from the combination of two factors, LMIF dilution and cell migration diameter, and therefore this made the LMIT much more sensitive as compared to the conventional LMIT. The responsiveness of lymphocytes from acute lymphoblastic leukemia (ALL) and from cell-mediated immunodeficiency in children to TF was assayed by LMIT. In ALL, the lymphocyte responsiveness was poor in relapse but improved with remission. The responsiveness was remarkably well in 3 patients with cell-mediated immunodeficiency. This method appears useful for the in vitro evaluation of responsiveness of lymphocytes to TF.  相似文献   

11.
As conventional treatments are unsuccessful, the survival rate of stage D3 prostate cancer patients is poor. Reports have suggested the existence of humoral and cell-mediated immunity (CMI) against prostate cancer tumour-associated antigens (TAA). These observations prompted us to treat stage D3 prostate cancer patients with an in vitro produced transfer factor (TF) able to transfer, in vitro and in vivo, CMI against bladder and prostate TAA. Fifty patients entered this study and received one intramuscular injection of 2–5 units of specific TF monthly. Follow-up, ranging from 1 to 9 years, showed that complete remission was achieved in 2 patients, partial remission in 6, and no progression of metastatic disease in 14. The median survival was 126 weeks, higher than the survival rates reported in the literature for patients of the same stage.  相似文献   

12.
Administration of prostaglandin synthetase inhibitors to pregnant does and dams in late gestation was followed by in utero contraction of the fetal ductus arteriosus when studied by the whole-body freezing method. In the rat this contraction was well established within 6 h and persisted up to 36 h following 15 mg/kg indomethacin p.o. No effect was observed in the 18 d rat fetus but fetuses at 20 d and 22 d of gestation responded significantly to indomethacin. Doses of indomethacin approaching clinical usage (2.5 mg/kg) also caused a positive response in utero. The rat was found to be sensitive also to sodium salicylate and in the rabbit both indomethacin and sodium salicylate were effective. Exposure in utero to prostaglandin synthetase inhibitors with resulting contraction of the ductus may seriously disturb cardiac function in the fetus.  相似文献   

13.
Ribosomal proteins L7L12 have been mapped by immune electron microscopy. These multiple copy proteins are located at a single region extending from the large subunit, known as the L7L12 stalk. The L7L12 stalk is approximately 100 Å long, about 40 Å wide and extends at an angle of approximately 50 ° from one side of the central protuberance of the large subunit. In the monomeric 70 S ribosome, the portion of the L7L12 stalk proximal to the 50 S subunit is located in the vicinity of the 30 S-50 S interface.Anti-L7L12 antibody binding to the stalk was shown to be solely dependent upon the presence of L7L12 by the following experiments. Sucrose gradient analysis was used to demonstrate that large subunits depleted of L7L12 were unable to bind anti-L7L12 antibodies and that re-incorporation of L7L12 restored the ability of L7L12-depleted cores to react with anti-L7L12 antibodies. Anti-L7L12 antibodies pre-absorbed with L7L12 did not react with 50 S subunits.Anti-L7L12 antibodies used in these experiments reacted only with the L7L12 stalk and with no other region of the subunit. This was shown by electron microscopy and by immune electron microscopy in the following ways. Electron microscopy of 50 S subunits, L7L12-depleted 50 S cores, and reconstituted 50 S subunits was used to demonstrate that stripping removes the L7L12 stalk from more than 95% of the subunits, and that re-incorporation of L7L12 into depleted cores restores the L7L12 stalk. Double-labelling experiments, using monomeric subunits with two or more attached anti-L7L12 immunoglobulins, were used to demonstrate, independently of 50 S subunit morphology, that L7L12 are located only on the L7L12 stalk.  相似文献   

14.
A total of 126 bovine embryos were surgically collected from 16 superovulated donor heifers 5 days after estrus and randomly selected for either immediate transfer to synchronized recipients or invitro culture at 37°C for 24 hours and subsequent transfer. Twenty-four of 56 (42.8%) embryos maintained for 24 hours in Ham's F10 medium supplemented with 10% heat treated fetal calf serum (HTFCS) and transferred to 32 recipients produced live calves. Survival of 70 noncultured embryos transferred to 35 recipients was 55.7% (39 calves). The percentages of recipients that were diagnosed pregnant at 42 days with cultured and control embryos were 59.4% (1932) and 74.3% (2635), respectively. No statistical difference was observed between the invitro cultured and control embryos for viability following transfer to recipient females.In a second study, Day 7 embryos maintained in Ham's F10 medium supplemented with 10% HTFC serum for various culture periods were tested for viability following nonsurgical transfer to recipient females. A total of 15, 13 and 04 embryos cultured for 24, 48 and 72 hours, respectively, resulted in pregnant recipients following transfer.  相似文献   

15.
Crystals of pyruvate kinase have been analysed by electron microscopy, optical diffraction and filtering, and the following parameters were obtained: 2a = 93 A?, 2b = 126A?, l = 35·2 A?. A comparison of these data with the parameters obtained from small-angle X-ray scattering measurements indicates that two molecules of the tetrameric enzyme are arranged in one packing unit.  相似文献   

16.
Electrophoretic analyses were performed to establish the polypeptide profiles of the following tick-borne typhus rickettsiae of the spotted fever group: Rickettsia rickettsii (Sheila Smith, Bitter Root, Iowa and R strains), R. sibirica, R. conorii, R. parkeri, R. australis and R. akari. Organisms were propagated in chick embryo fibroblast cells in roller bottles and purified by density centrifugation. After polyacrylamide gel electrophoresis, comparative electrophoretic profiles were examined by densitometric scanning. Of the more than 20 separate polypeptides detected, six of the most prominent were found in all rickettsiae examined except R. akari. No carbohydrate-containing moieties were detected in electrophoretic gels.  相似文献   

17.
The courses of infection in inbred mouse strains were compared following infection with three Stabilates of high, intermediate, and low virulence of Trypanosoma vivax stock Zaria Y486. Mouse strains could only be shown to differ in their resistance to T. vivax infections as judged by the height of the initial parasitemia and survival times when a trypanosome population of low or intermediate virulence was used. A T. vivax population of high virulence was uniformly lethal. Comparison of lytic antibody titers between groups of resistant (C57B16) and susceptible (Balbc) mice did not show any significant differences in titers of the surviving mice but the mice in either group which did not control the initial parasitemia had lower lytic antibody titers than those which did. A significantly larger number of Balbc mice failed to control the initial infection as compared to the C57B16. Treatment with cyclophosphamide did not ablate differences in susceptibility between the two strains. The use of congenic mice showed that these differences in susceptibility were not related to differences in the major histocompatibility complex between these strains.  相似文献   

18.
Summary A total of 122 sera from acute lymphoblastic leukemia (ALL) patients were analyzed for circulating immune complexes (CIC) by two methods: the 125I-C1q binding assay and the polyethylene glycol precipitation test (PEG). The results were correlated with induction, remission and relapse stages of the disease. Using the first method the levels of CIC in induction were 15.18±9.15, with 19/29 positive cases (65.50%), P<0.001 compared with controls. In the remission phase the levels were 9.02±5.62, 11/45 (24.49%) nonsignificant P value, and in relapse they were 16.14±11.17 28/48 (58.33%) P<0.001. The PEG precipitation test results were: 0.33±0.10, 8/22 (36.36%); 0.24±0.11, 10/48 (20.83%) and 0.28±0.10, 6/28 (21.42%), respectively. Thus the values of CIC as measured by PEG in the three clinical of phases ALL did not differ significantly from controls. This contrasts with results obtained by the radioiodinated C1q binding assay, where the incidence of positive values was significantly higher in induction and in relapse and lower in the remission phase. These observations were extended in sequential vertical studies performed in a group of patients. These results suggest that raised CIC detected by the 125I-C1q method may reflect a progressive state in ALL and that quantitation of these immune complexes may provide an adequate biochemical marker for prognosis.  相似文献   

19.
Antibody responses and host resistance to the tapeworm, Hymenolepis microstoma, were investigated using AKRJ and C3HeBFeJ strains of mice. AKR mice were significantly more resistant than controls to a secondary infection following exposure to a 3-, 21-, or 40-day primary infection. During a primary infection, intestinal anti-worm antibody responses measured by an enzyme-linked immunosorbent assay were elevated in the more resistant AKR strain, whereas serum antibody titers did not differ between the two strains. However, during a secondary infection, serum IgA titers were higher in AKR mice than C3H mice. Suppression of the serum IgA anti-worm response by oral administration of lipopolysaccharide also suppressed resistance to a secondary infection. Intraperitoneal immunization with worm antigen resulted in a minor degree of protection in AKR mice. This protection was associated with increased intestinal antibody titers compared to mice not demonstrating protection. These results suggest that the protective responses observed in AKR mice relative to C3H mice reflect differences in mucosal antibody responses to H. microstoma.  相似文献   

20.
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