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1.
In vitro studies were conducted in the non-obese diabetic (NOD) mouse, prone to Type 1 autoimmune diabetes, to investigate the mechanisms involved in cell-mediated rejection of pig islet xenografts. Our previous work concerning the mechanisms of proliferation of xenogeneic lymphocytes to pig islet cells (PIC) was not indicative of PIC impairment. Consequently, a test was developed based on perifusion analysis of the alteration of basal and stimulated insulin release from adult PIC incubated with mouse splenocytes or subsets. Compared with PIC incubation alone or with syngeneic pig splenocytes, co-incubation with mouse whole spleen cells resulted in a decrease of basal and stimulated insulin release (P < 0.001). Two components of this alteration were detected separately: PIC impairment was decreased (P < 0.01) after removal of plastic-adherent cells from spleen cells, but maintained (P < 0.01) when plastic-adherent cells alone were co-incubated with PIC. The increase of murine interleukin-1 beta when mouse plastic-adherent spleen cells were cultured with PIC (P < 0.04) was indicative of macrophage activation. Soluble factors produced during co-incubation of mouse splenocytes or plastic-adherent cells with PIC were involved in the impairment process, since supernatant fluids collected during previous PIC-mouse cell co-incubations directly altered (P < 0.01) insulin release from PIC. Moreover, impairment of PIC by mouse spleen cells was abolished (P < 0.01) by gadolinium chloride (which inhibits macrophages), but not by cyclosporin A. Another mechanism was apparent, since co-incubation of PIC with purified mouse T cells or CD4+ T cells, re-mixed with antigen-presenting cells, led to a decrease (P < 0.01) of insulin release. This model, based on the alteration of dynamic basal and stimulated insulin release, is indicative of in vitro cell-mediated alteration of PIC in the NOD mouse. The effect of whole spleen cells was rapid, and a crucial role was played by plastic-adherent cells. Two mechanisms were responsible for the behaviour of these cells: an early direct effect (at least in part via soluble products); and the indirect presentation of PIC xenoantigens (leading to impairment by CD4+ T lymphocytes).  相似文献   

2.
Because the different steps of the human cellular immune rejection of pig islets are still poorly understood, our previous work concerned the intensity and mechanisms of the proliferation of human peripheral blood mononuclear cells (PBMC) to adult pig islet cells (PIC). As lymphocyte proliferation is not indicative of alteration of PIC, the present in vitro study evaluated cell-mediated immune effectors possibly involved in impairment of adult PIC. A test was thus developed, based on perifusion analysis of the alteration of insulin release from PIC incubated with different human cells. Compared to PIC incubation alone or with autologous pig splenocytes, seven-day co-incubation with whole human peripheral blood mononuclear cells (PBMC) (n = 18) led to almost complete abolition of basal and stimulated insulin releases (p < 0.0001). This effect could not be reversed by extensive sequential washes before perifusion of PIC, and the number of PIC was decreased by 78% after seven-day co-incubation with PBMC. PBMC are a complex mixture of cells involved in different xenogeneic mechanisms, and two components of this PIC impairment were then detected separately. First, the effect of PBMC against PIC was decreased (p < 0.0001) after removal of either MHC class II+ or CD14+ cells from PBMC. On the contrary, decreasing effect (p < 0.001) on insulin secretion was observed when only plastic-adherent or CD14+ cells were co-incubated with PIC. Additionally, alteration of insulin release from PIC cultured with PBMC or plastic-adherent cells was abolished dose-dependently (p < 0.0001 and p < 0.04, respectively) by gadolinium chloride (which inhibits macrophages), but not modified by cyclosporin A or mycophenolate mofetil which did not alter insulin release from PIC but blocked the proliferation of PBMC against PIC. A second mechanism was also detected, since co-incubation of PIC with purified human T cells remixed with antigen-presenting cells led to a decrease (p < 0.0001) of insulin release. This model based on the alteration of dynamic basal and stimulated insulin secretion provides detailed account of in vitro human cell-mediated impairment of PIC. It shows that the xenogeneic effect of whole mononuclear cells was strong and rapid. A crucial role was played by MHC class II+, CD14+, and plastic-adherent cells. Two mechanisms appear to be responsible for the role of these cells: 1) early direct effect, potentially involved in vivo in primary nonfunction of islets aggressed by monocytes/macrophages; and 2) the presentation of PIC xenoantigens leading to impairment by T lymphocytes, which may be involved in in vivo specific cellular rejection.  相似文献   

3.
1. Homologous and heterologous colostral immune globulins and human serum albumin were fed to new-born pigs and an attempt was made to estimate the amounts appearing subsequently in serum.2. All three proteins, fed separately in large amounts to different pigs, appeared in the serum in low concentration about 45 min after feeding, and then rose quickly to a high level. No difference could be detected between the amounts absorbed when equal amounts had been fed but there was a wide variation between pigs. Previous dialysis of pig colostrum against bicarbonate saline did not affect the rate or amount of pig immune globulin absorbed after feeding.3. When pig and bovine colostral IgG were fed together at equal concentrations in bovine colostrum, the absorption of pig IgG was greater than that of bovine IgG. Human serum albumin, added to bovine colostral IgG in bovine colostrum, was absorbed readily and this did not interfere significantly with the absorption of bovine colostral IgG.4. The efficiency with which the pig intestine absorbed bovine colostral IgG depended on the dose and/or concentration fed, increasing as the dose fed was increased to 2 g and remaining constant for higher doses.5. Some of the absorbed immune globulin was shown to exist in a partly degraded form.6. The process of protein transfer across the intestine of the new-born pig may select, to a limited degree, between different proteins, but the digestion of protein shown to take place and the large variation between individual pigs makes interpretation of these results uncertain.  相似文献   

4.
Small size at birth has been associated with increased blood pressure in adult men and women. In rats, isocaloric protein restriction reduces fetal growth and increases systolic blood pressure in adult offspring. Balanced maternal undernutrition in the rat also increases adult blood pressure, but not consistently. The aim of this study was to determine the effect of moderate balanced maternal undernutrition (85% of ad libitum intake from 4 weeks before, and throughout pregnancy) on blood pressure of adult offspring in the guinea pig, a species that is relatively mature at birth. Blood pressure was measured in chronically catheterised offspring of ad libitum fed or feed-restricted mothers, at 3 months of age (young adult). Maternal feed restriction reduced birth weight (-17%) and increased systolic blood pressure (+9%, P < 0.03) in young adult male offspring. In offspring of ad libitum fed and feed-restricted mothers, combined data showed that systolic blood pressure and mean arterial pressure correlated negatively with head width at birth (P = 0.02 and P = 0.04, respectively, n = 28). Systolic blood pressure also correlated negatively with birth weight and the ratio birth weight/birth length, but only in offspring of ad libitum fed mothers (P = 0.04 and P = 0.03, respectively, n = 22). The effect of maternal feed restriction on systolic blood pressure in male offspring was not significant when adjusted for these measures of size at birth. Thus, moderate balanced undernutrition in the guinea pig increases systolic blood pressure in young adult male offspring; however, these effects may be mediated, at least in part, through effects on fetal growth.  相似文献   

5.
Aims:  Gallbladder involvement in autoimmune pancreatitis (AIP) is reported to be histologically similar to that seen in primary sclerosing cholangitis (PSC) and biliary obstruction secondary to pancreatic ductal adenocarcinoma (PDAC). The aim was to identify unique morphological and immunological features that could help distinguish gallbladders of AIP from those associated with PSC and PDACs.
Methods and results:  Archival gallbladders from well-characterized individuals with AIP ( n  = 22), PSC ( n  = 13) and PDAC ( n  = 23) were examined. Quantitative immunohistochemical analysis for IgG and IgG4 plasma cells was performed and an IgG4/IgG ratio was derived. Dense extramural infiltrates were almost exclusively seen in AIP cases (41%), but seen in only 4% of PDAC-associated cases and 0% of PSC cases ( P  = 0.001). Phlebitis was more frequently noted in AIP cases (41%) ( P  = 0.03). Inflammatory nodules were almost exclusively seen in AIP (27%) ( P  = 0.04). AIP gallbladders showed higher IgG4/IgG ratios ( P  = 0.0001) than PDAC-associated and PSC gallbladders.
Conclusions:  The findings support our hypothesis that gallbladder involvement in AIP is a primary manifestation of this disease and not a secondary phenomenon related to biliary obstruction. In conjunction with imaging and serology, examination of the gallbladder could provide collaborative evidence of AIP. Evaluation of the gallbladder could also distinguish PSC from AIP-related cholangitis.  相似文献   

6.
In the graft rejection of transplanted islets, the host's immune cells recognize the islets as antigens, which then stimulate the immune cells to begin the cytokine secretion and also the proliferation of immune cells. To prevent the recognition of islets by the immune cells, we grafted biocompatible polyethylene glycol (PEG) onto the collagen capsule of islets without incurring any changes in the morphology and function of islets. To evaluate the efficiency of PEG grafting, PEGgrafted islets were cultured with splenocytes consisting mainly of lymphocytes and macrophages. A splenocyte proliferation assessment using a BrdU incorporation assay showed that the PEG-grafted islets did not stimulate the splenocytes. In addition, the viability and microorganisms in islet cells of co-cultured PEG-grafted islets were not altered. However, in the co-culture of free islets (control) splenocytes were stimulated; they mainly secreted TNF-α and strongly affected the viability and structure of free islets. Furthermore, when islets were treated with the rat recombinant TNF-α for 7 days, the viabilities of PEG-grafted and free islets were significantly damaged, although the viability of PEG-grafted islets was higher than that of free islets by nearly three times. These results demonstrate that PEG grafted on the surface of islets could prevent the recognition of islets by splenocytes, but could not completely protect islets from cytokines.  相似文献   

7.
In the graft rejection of transplanted islets, the host's immune cells recognize the islets as antigens, which then stimulate the immune cells to begin the cytokine secretion and also the proliferation of immune cells. To prevent the recognition of islets by the immune cells, we grafted biocompatible polyethylene glycol (PEG) onto the collagen capsule of islets without incurring any changes in the morphology and function of islets. To evaluate the efficiency of PEG grafting, PEG-grafted islets were cultured with splenocytes consisting mainly of lymphocytes and macrophages. A splenocyte proliferation assessment using a BrdU incorporation assay showed that the PEG-grafted islets did not stimulate the splenocytes. In addition, the viability and microorganisms in islet cells of co-cultured PEG-grafted islets were not altered. However, in the co-culture of free islets (control) splenocytes were stimulated; they mainly secreted TNF-alpha and strongly affected the viability and structure of free islets. Furthermore, when islets were treated with the rat recombinant TNF-alpha for 7 days, the viabilities of PEG-grafted and free islets were significantly damaged, although the viability of PEG-grafted islets was higher than that of free islets by nearly three times. These results demonstrate that PEG grafted on the surface of islets could prevent the recognition of islets by splenocytes, but could not completely protect islets from cytokines.  相似文献   

8.
The role of endogenous gamma interferon (IFN-gamma) in protective immunity against blood-stage Plasmodium chabaudi AS malaria was studied using IFN-gamma gene knockout (GKO) and wild-type (WT) C57BL/6 mice. Following infection with 10(6) parasitized erythrocytes, GKO mice developed significantly higher parasitemia during acute infection than WT mice and had severe mortality. In infected GKO mice, production of interleukin 12 (IL-12) p70 and tumor necrosis factor alpha in vivo and IL-12 p70 in vitro by splenic macrophages was significantly reduced compared to that in WT mice and the enhanced nitric oxide (NO) production observed in infected WT mice was completely absent. WT and GKO mice had comparable numbers of total nucleated spleen cells and B220(+) and Mac-1(+) spleen cells both before and after infection. Infected WT mice, however, had significantly more F4/80(+), NK1.1(+), and F4/80(+)Ia(+) spleen cells than infected GKO mice; male WT had more CD3(+) cells than male GKO mice. In comparison with those from WT mice, splenocytes from infected GKO mice had significantly higher proliferation in vitro in response to parasite antigen or concanavalin A stimulation and produced significantly higher levels of IL-10 in response to parasite antigen. Infected WT mice produced more parasite-specific immunoglobulin M (IgM), IgG2a, and IgG3 and less IgG1 than GKO mice. Significant gender differences in both GKO and WT mice in peak parasitemia levels, mortality, phenotypes of spleen cells, and proliferation of and cytokine production by splenocytes in vitro were apparent during infection. These results thus provide unequivocal evidence for the central role of endogenous IFN-gamma in the development of protective immunity against blood-stage P. chabaudi AS.  相似文献   

9.
10.
Chronic graft versus host disease (cGVHD) is the result of an immune-mediated attack by transplanted donor lymphocytes, entailing inflammatory damage to host target organs. Clinically, the post-bone marrow transplantation (BMT) graft versus leukemia (GVL) effect may be associated with GVHD. Immune hyporesponsiveness induced by oral antigen administration has recently been shown to prevent the development of cGVHD in a murine model. To evaluate whether amelioration of cGVHD in mice by induction of oral immune regulation in donors toward recipient pretransplant lymphocyte antigens is associated with attenuation of the GVL effect donor B10.D2 mice were fed with Balb/c splenocytes, B10.D2 splenocytes, bovine serum albumin (BSA), or regular chow, every other day for 10 days. Subsequently, transplantation of 2 x 10(7) splenocytes from donor B10.D2 mice to recipient Balb/c mice was undertaken, followed by inoculation of 3 x 10(3) BCL-1 leukemia on the day of BMT. Control groups were fed identically without leukemia inoculation. Mice were followed for survival and leukemia progression. Induction of tolerance was assessed by a mixed lymphocyte reaction (MLR). Cutaneous GVHD was assessed macroscopically. To elucidate the mechanism of any observed effect, serum interferon (IFN), interleukin (IL-2), IL-12, IL-4, and IL-10 were determined by enzyme-linked immunosorbent assay and flow cytometry analysis for CD4+, CD8+, and NK1.1+ lymphocyte subpopulations was performed. There was no significant difference in leukemia progression manifested by survival or white blood cell counts of orally immune-regulated mice compared with control animals. Cutaneous cGVHD was significantly ameliorated in Balb/c mice transplanted from tolerized B10.D2 mice. This effect was associated with a significant reduction in the mixed lymphocyte response of effector splenocytes from tolerized B10.D2 mice against Balb/c target splenocytes; significantly decreased serum IFN-gamma and IL-2; increased serum IL-12 levels; increased peripheral NK1.1+ cells; and CD4+/CD8+ lymphocyte ratio. Oral tolerization of BMT donors toward recipient antigens ameliorates cGVHD without hampering the GVL effect.  相似文献   

11.
Florfenicol is a new type of broad-spectrum antibacterial that has been used in veterinary clinics. It shows immunosuppressive activity on the immune responses to ovalbumin (OVA) in mice. In the present study, florfenicol suppressed lipopolysaccharide (LPS)-stimulated splenocyte proliferation in a concentration-dependent manner in vitro and in vivo. BALB/c mice were immunized subcutaneously with OVA on days 1 and 4. Following the second immunization, mice were treated with a single daily oral dose of florfenicol (50, 100, and 200 mg/kg) for 10 consecutive days. On day 14, blood samples were collected to analyze OVA-specific IgG, IgG1, and IgG2b antibodies, and splenocytes were harvested to assess lymphocyte proliferation, CD3+ T and CD19+ B lymphocyte subsets. The results presented here demonstrate that florfenicol not only significantly suppressed Con A-, LPS- and OVA-induced splenocyte proliferation but also decreased the percentage of CD19+ B cells in a dose-dependent manner and suppressed CD3+ T cell at high doses. Moreover, OVA-specific IgG, IgG1 and IgG2b titers in OVA-immunized mice were reduced by florfenicol. These results suggest that florfenicol could suppress humoral and cellular immune responses in mice.  相似文献   

12.
BACKGROUND: Some patients outgrow their food allergies even though their serum antigen-specific IgE levels remain high. OBJECTIVE: To elucidate the role of T cells in outgrowing food allergies in the presence of antigen-specific IgE, we tracked antigen-specific T-cell responses after oral antigen administration. METHODS: Ovalbumin (OVA)-specific T-cell receptor (TCR) and OVA-specific IgE transgenic (Tg) mice (OVA-TCR/IgE-Tg) and OVA-specific TCR Tg (OVA-TCR-Tg) mice were fed with high doses of OVA or PBS every other day. After 7 administrations, OVA-specific proliferation and cytokine production of mononuclear cells of the spleen, mesenteric lymph nodes, and Peyer's patches and the number of splenic CD4 + CD25 + T cells were analyzed. RESULTS: Without OVA administration, the splenocytes from OVA-TCR/IgE-Tg mice exhibited a higher proliferative response and produced more IL-4 and IL-10 and less IFN-gamma than those from OVA-TCR-Tg mice. The proliferative responses of the splenocytes from either OVA-TCR/IgE-Tg mice or OVA-TCR-Tg mice fed with OVA were significantly reduced compared with those from PBS-fed mice. The number of OVA-specific TCR + T cells decreased in the spleen from OVA-fed mice, whereas the number of CD4 + CD25 + T cells increased. The suppressed proliferation of splenocytes of OVA-fed mice was partially resumed by neutralization of TGF-beta1, but not of IL-10. CONCLUSION: The presence of OVA-specific IgE modulated the OVA-specific responses of the splenocytes. Irrespective of the presence of OVA-specific IgE, repetitive oral administration of OVA induced tolerance, which seems to be composed of clonal deletion/anergy and TGF-beta1-mediated active suppression.  相似文献   

13.
Citation
Hemadi M, Shokri S, Pourmatroud E, Moramezi F, Khodadai A. Follicular dynamic and immunoreactions of the vitrified ovarian graft after host treatment with variable regimens of melatonin. Am J Reprod Immunol 2012; 67: 401–412 Problem This study investigates dose‐dependent effects of melatonin on ovarian graft. Method of Study Vitrified‐thawed whole ovaries of newborn mice were grafted into ovariectomized mature ones. Melatonin (20, 50, 100, and 200 mg/kg/day) was administrated to separate groups of host mice for 32 days. IgM and IgG antibodies, Th1 and Th2 cytokines, and melatonin in recipient’s blood were measured. Subsequent survival of the grafted ovaries was scored. An assessment of follicular morphology was performed using TUNEL assay and hematoxylin‐eosin staining. Results The administration of melatonin did not disturb the circadian rhythm of melatonin concentration. The ovarian graft lifespan was prolonged at 200 mg/kg/day melatonin (P < 0.001). However, in doses of higher than 20 mg/kg/day melatonin, the proportion of healthy follicles and ovary size decreased. Th1 cytokines levels were reduced dose dependently. However, the effect of melatonin on Th2 cytokines was not pronounced. IgM and IgG2a decreased in recipients receiving 200 mg/kg/day melatonin in comparison with non‐treated group (P < 0.001), while this variables were significantly increased at the dose of 50 mg/kg/day (P < 0.001). Conclusion Melatonin at 200 mg/kg/day has an immunosuppresent effect and produce prolongation of graft survival. However, the associated reduction in healthy follicles suggests that melatonin in doses of higher than 20 mg/kg/day has no preventative ischemic action.  相似文献   

14.
Bo-yang-hwan-o-tang (BHT) has long been used to treat cancer in traditional Korean medicine and is believed to have immune-modulating activity. This study investigated the effect of BHT on the induction of antigen-specific immune responses using hen egg-white lysozyme (HEL) as a model antigen system. Oral administration of BHT enhanced both HEL-specific humoral and lymphocyte proliferative responses in HEL low-responder mice. Feeding BHT to the mice increased INF-gamma levels, but did not change IL-4 levels. Interestingly, however, the oral BHT feeding significantly increased HEL-specific antibodies of the IgG1, IgG2b, and IgG3 subtypes, which are associated with the direct stimulation of B cells. This indicates that BHT treatment enhances anti-HEL-specific humoral immune responses via the direct stimulation of B lymphocytes rather than by selective priming of specific subtypes of the helper T-cell population. This conclusion was supported by in vitro experiments, in which the presence of BHT significantly augmented B-cell mitogen-mediated proliferation of mouse splenocytes. This augmentation was closely associated with a glycoprotein with a molecular weight of around 100 kDa. The results suggest that BHT modulates antigen-specific immune responses, and might be used as a therapeutic agent for patients who need enhanced immune function.  相似文献   

15.
In 4-month-old leukemia-prone AKR mice, the ability of bone marrow cells to inhibit proliferation of concanavalin A-stimulated splenocytes and mastocytoma P815 cellsin vitro was sharply increased in the preleukemic period. In 7-month-old mice, differences in natural suppressive activity of bone marrow cells were significant, but less pronounced than in 4-month-old mice. The immunosuppressive activity was not found in the spleen. In 4-month-old AKR mice, in the inhibition of proliferation of mitogen-stimulated splenocytes was increased due to enhanced NO production by bone marrow cells. These findings suggest that the increased antiproliferative activity observed in the bone marrow of AKR mice long before the appearance of clinical manifestations of leukemia is associated with disturbances in differentiation of myeloid progenitor cells and accumulation of natural suppressor cells in the bone marrow. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 4, pp. 452–454, April, 1999  相似文献   

16.
Wu WM  Suen JL  Lin BF  Chiang BL 《Immunology》2000,100(1):110-118
Previous study suggested that MRL-lpr/lpr mice treated with tamoxifen (TAM) had less severe proteinuria, reduced serum titre of anti-dsDNA autoantibodies and an increased survival rate. To investigate further the regulatory mechanisms of TAM on MRL-lpr/lpr female mice, a total dose of 200 microg per mice (5.5 mg/kg) was given every 2 weeks subcutaneously, while the control mice were injected with oil only. After being treated with TAM four times, the mice were killed and cellular functions were evaluated. The TAM-treated groups had smaller sized spleen and lymph nodes. Flow cytometric analysis of splenocytes had a significantly lower percentage of cell number of T cells and double negative T cells (CD4- CD8- T cells). There was no difference in cytokine production (interleukin (IL)-2, IL-4, IL-5, IL-10 and interferon-gamma (IFN-gamma)) from splenocytes stimulated with concanavalin A (Con A) or cytokines (IL-6) secreted by peritoneal exudate cells when stimulated with lipopolysaccharide (LPS). However, IL-2 from lymph node cells was significantly higher on TAM-treated mice. Finally, splenocytes or purified T cells stimulated with anti-CD3 antibody plus cross-linking immunoglobulin G (IgG) of the TAM-treated group had higher 3H-incorporation of proliferation assay compared with that of control groups. In vitro study further demonstrated that IL-2-activated proliferation of lymph node double negative (DN) T cells can be inhibited by TAM treatment in a dose-dependent manner. Our finding demonstrated that TAM may potentially influence T cells and modulate the immune function, which offers a novel approach to explore the feasibility of hormone therapy for autoimmune diseases.  相似文献   

17.
Salidroside, a major component of Rhodiola rosea L., was evaluated for its adjuvant effects on the immune responses in mice by ovalbumin (OVA) stimulation. BALB/c mice were immunized subcutaneously with OVA 100 μg or OVA 100 μg dissolved in saline containing alum (100 μg) or salidroside (12.5, 25, or 50 μg) on Days 1 and 15. Two weeks later (Day 28), blood samples were collected to analyze OVA-specific IgG, IgG1, and IgG2b antibodies. Meanwhile, splenocytes were harvested to assess lymphocyte proliferation, cytokines (IL-2, IL-4, and IFN-γ) production, and CD4+, CD8+ lymphocyte subsets. The results indicated that co-administration of salidroside with OVA significantly enhanced the ConA-, LPS-, and OVA-induced splenocyte proliferation, produced more IL-2, IL-4, IFN-γ, and IgG, IgG1, and IgG2b antibody levels, and increased the percentage of CD4+, CD8+ lymphocyte subsets than OVA alone. Thus, salidroside possess immunological adjuvant activity by regulating humoral and cellular immune responses in mice.  相似文献   

18.
First generations of milk protein exempted mice (6–8 weeks old) were fed with casein at 100 mg per day. At 0, 2, 4, 6, 8, 12 and 20 weeks of feeding, a group of eight mice was sacrificed to recover spleen lymphocytes and intraperitoneal mastocytes. In vitro lymphocyte 3H‐thymidine incorporation in the presence of intact casein, peptic or peptic‐tryptic‐chymotryptic hydrolysate was significantly higher at eight and 12 weeks of feeding (p<0.05). The number of the sensitized mice increased from 39% in the control group to 61% in the experimental groups. The three antigens possessed a statistically equal capacity to stimulate lymphocyte proliferation. Measurements of plasma and culture supernatant IgG antibody production exhibited an elevated enzyme‐linked immunosorbent assay value starting from the eight week of casein feeding. Casein feeding also provoked histamine accumulation in the mastocytes which occured significantly after four weeks of feeding (p<0.001). The fact that the lymphocytes recognized not only intact casein but also its digestive enzyme hydrolyzates indicate that intestinal digestion and absorption processes could neither totally block the antigen passage nor destroy their epitopes.  相似文献   

19.
抗人CD154单克隆抗体抑制免疫应答的实验研究   总被引:1,自引:2,他引:1  
目的:探讨抗人CD154单克隆抗体对免疫应答的抑制作用。方法:①在体外进行混合淋巴细胞反应,研究抗人CD154单克隆抗体对淋巴细胞增殖反应的影响;②在严重免疫联合缺陷(SCID)鼠体内重建人的免疫功能后,研究抗人CD154单克隆抗体在SCID小鼠体内对T细胞增殖的影响和对B细胞功能的影响。结果:①双向混合淋巴细胞反应结果显示,抗体的5个剂量组的[3H]-TdR的掺入率均显著低于对照组(均P<0.01);②在输注人外周血单个核细胞第6d、第12d、第21d,实验组SCID鼠体内人T细胞占SCID鼠淋巴细胞的百分率均明显低于对照组(均P<0.05);在输注人外周血单个核细胞后的第12d、第21d、第31d,实验组SCID鼠体内人IgG的含量明显低于对照组(均P<0.05)。结论:抗人CD154单克隆抗体能够在体外抑制淋巴细胞的增殖,在SCID小鼠体内能够抑制T细胞的增殖和IgG的产生。  相似文献   

20.
Insomnia: symptom or diagnosis?   总被引:5,自引:0,他引:5  
Is insomnia a clinical entity in its own right or is it simply a symptom of an underlying medical or psychological disorder? The widely held view among many clinicians and researchers is that insomnia is secondary to or an epiphenomenon of a 'primary' medical or psychological disorder. Consequently, insomnia 'symptoms' have tended to be trivialized or ignored. This paper aims to highlight the assumptions and implications of distinguishing between 'primary' and 'secondary' insomnia and reviews the evidence for the distinction by considering (1) issues relating to the diagnosis and classification of insomnia, (2) whether insomnia is a symptom of other medical and psychological disorders, (3) whether insomnia is comorbid with other disorders, (4) whether insomnia is 'secondary' to other disorders, and (5) whether insomnia occurs in the absence of comorbidity. It is concluded that viewing insomnia as a symptom or epiphenomenon of other disorders can be unfounded. This view may deprive many patients of treatment, which might not only cure their insomnia, but may also reduce symptoms associated with the assumed 'primary' disorder. Finally, directions for future research to further illuminate the relationship between insomnia and comorbid disorders are discussed.  相似文献   

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