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1.
C Bell  S Dray 《Science (New York, N.Y.)》1971,171(967):199-201
Ribonucleic acid extracts obtained from lymph nodes of immunized rabbits homozygous for the b(4)or b(5)allele of light chain immunoglobulin allotypes were injected intravenously into nonimmunized rabbits homozygous for the alternate allele. Approximately 30 percent of the plaque-forming cells in the spleen yielded plaques with immunoglobulin M antibody possessing the allotype of the RNA donor. The allotype of the RNA donor was also found in the IgG immunoglobulin of lymphoid cell lysates as well as in the IgG isolated from the serum. These results suggest that the injected RNA has an informational role in the in vivo synthesis of immunoglobulins by host lymphoid cells.  相似文献   

2.
Recent results emphasize the roles of T-independent antibody response in humoral defenses, for which B1 cells and marginal zone B cells are mostly responsible. We discuss how these cells are activated, migrate, and differentiate into antibody-producing cells in various lymphoid tissues. Based on recent findings in each of these areas of B cell biology, we propose a possible mechanism for peripheral tolerance of autoreactive B cells at target organs.  相似文献   

3.
When Lewis rats were exposed to antilymphocytic serum, produced in rabbits, to Lewis lymphoid cells, the transformation of their thoracic duct lymphocytes in response to foreign lymphoid cells was markedly reduced in comparison with that in response to similar cells from donors treated with saline or normal rabbit serum. It is suggested that the mixed lymphocyte reaction may be used as an in vitro test for the in vivo activity of antilymphocytic serum.  相似文献   

4.
60只1日龄肉雏鸡平均分成A、B、C三组。A组于1日龄手术切除哈德氏腺,12日龄时A、B两和新城疫疫苗点眼,C组为非免疫对照组。23日龄时,采集泪液和血清做血凝抑制(HI)试验,同时采取哈德氏腺、结膜结合淋巴组织(CALT)和泪腺做组织切片。结果,A组血清抗体水平与B组相当,泪液则显著降低,但比C组高得多。B组泪液抗体效价比血清高,差异极显著。组织学观察,A组泪腺上皮下有明显的淋巴小结,少数雏鸡原  相似文献   

5.
Primary-type antibody response in vitro   总被引:10,自引:0,他引:10  
T W Tao  J W Uhr 《Science (New York, N.Y.)》1966,151(714):1096-1098
Organ cultures of lymph nodes obtained from nonimmunized rabbits were incubated with bacteriophage d, X174; as a result, 19S antibody was produced first, and then 7S antibody. Differences between this response and the secondary response to d? X174 induced in vitro suggest that the foriiier is a primary response.  相似文献   

6.
Experiments were conducted to determine the effects of advanced vaccination and Chinese herbal adjuvants (CHA), containing astragalus polysaccharides (APS) and ginsenosides (GS) on the immune response to rabbit hemorrhagic disease (RHD) vaccine in young rabbits. In experiment 1, 5 New Zealand rabbits of each group at 30, 35, 40, or 45 days of age were injected with 2 mL of inactivated RHD vaccine, respectively. The dynamic changes of antibody titers were tested by the hemagglutination inhibition (HI) method. In experiment 2, 30 New Zealand rabbits at 35 days of age were randomly assigned to 5 treatment groups, representing inoculation with 3 mL of non-adjuvant RHD vaccine, CHA-RHD vaccine, CHA-HA vaccine (half dose antigen), aluminium adjuvant-RHD vaccine, and PBS, respectively. The dynamic changes of peripheral lymphocyte proliferation and serum antibody titers were tested by the MTT method and the HI method. The results showed that the titer of maternal HI antibody in the 35-day-old rabbits was lower than the protective level of 3 log2, while on days 7 to 49 after the vaccination, the antibody titers were higher than 3 log2. The CHA promoted the lymphocyte proliferation and enhanced the serum antibody titer (P〈 0.05). These findings from the two experiments suggested that advanced vaccination and Chinese herbal adjuvants significantly enhanced the immune response to vaccine against RHD, and effectively protected the young rabbits against RHD challenge.  相似文献   

7.
The antigen receptor of lymphocytes destined to form antibody appears to have the characteristics of the immunoglobulin produced. Antibody directed against the combining region of this immunoglobulin should interact with the combining region of the cell receptor for the antigen. Purified Lewis rat alloantibody prepared against Brown Norway (BN) rat histocompatibility antigens was used to immunize L x BN F(1) hybrids. The resultant antiserum has anti-receptor activity because (i) it yields precipitin lines in gel diffusion when reacted against the immunizing alloantibody; (ii) it inhibits the hemagglutinin antibody response of Lewis rats to BN histocompatibility antigens; and (iii) it inhibits the local graft-versus-host response of Lewis lymphoid cells against BN antigens. This suggests that antireceptor antibody may inhibit cell-mediated responses as well as antibody responses to histocompatibility antigens and may play a role in the regulation of immune responses to such antigens.  相似文献   

8.
原核表达的兔出血症病毒衣壳蛋白对兔的免疫保护效果   总被引:4,自引:0,他引:4  
 为了检验大肠杆菌表达的兔出血症病毒(RHDV)衣壳蛋白(VP60)对兔的免疫保护效果,将34只清洁兔随机分成3组:单用免疫佐剂对照组(8只)、单用重组VP60组(8只)和重组VP60加免疫佐剂组(18只),分别经皮下注射,VP60的免疫剂量为每只每次400 μg,免疫2次,间隔7 d。在第2次免疫7 d后,VP60加免疫佐剂组的兔血清抗体水平显著高于单用VP60免疫组(ELISA 1∶64 000 对比1∶4 000 / HI 1∶128 对比1∶16),表明免疫佐剂可明显加速重组VP60诱导抗体产生的进程,用RHDV NJ85强毒攻击,免疫佐剂对照组与单用VP60免疫组的实验兔均全部死亡(8/8和8/8),VP60加免疫佐剂组均全部存活,保护率为100%(18/18)。用RHDV血凝试验(HA)检测,死亡兔的肝脏组织液HA效价大于1∶512,而存活兔的肝脏组织液HA效价小于1∶2,肝脏组织触(涂)片检查和细菌培养均为阴性,证明病死兔系RHDV感染所致。用RHD重组亚单位疫苗在养兔场进行800只兔的田间免疫试验,安全有效,没有出现不良反应。对重组菌进行冻存、复苏、培养、诱导表达和质粒酶切分析,证明VP60基因在宿主菌内保持稳定。  相似文献   

9.
Preferential localization of effector memory cells in nonlymphoid tissue   总被引:1,自引:0,他引:1  
Many intracellular pathogens infect a broad range of host tissues, but the importance of T cells for immunity in these sites is unclear because most of our understanding of antimicrobial T cell responses comes from analyses of lymphoid tissue. Here, we show that in response to viral or bacterial infection, antigen-specific CD8 T cells migrated to nonlymphoid tissues and were present as long-lived memory cells. Strikingly, CD8 memory T cells isolated from nonlymphoid tissues exhibited effector levels of lytic activity directly ex vivo, in contrast to their splenic counterparts. These results point to the existence of a population of extralymphoid effector memory T cells poised for immediate response to infection.  相似文献   

10.
J Miller 《Science (New York, N.Y.)》1966,151(716):1395-1397
The spleen and thymus of 6-week-old mice contain similar numbers of lymphoid cells. A lethal dose of x-irradiation given to animials whose thymus, midgut, or hindlimbs were shielded at the same time resulted in permanent acceptance of allografts, while a similar dose given to spleen-shielded mice so irradiated resulted in a normal rejection pattern. The return of immunological competence was related to the state of the lymphoid organs with different types of shielding.  相似文献   

11.
研究了番鸭法氏囊柄部淋巴组织的分布及组织学结构。番鸭法氏囊柄部分布有多量的淋巴组织,以法氏囊柄的背侧淋巴组织分布面积最大、数量最多。其组织学结构包括淋巴相关上皮、上皮内淋巴细胞、圆顶区、淋巴滤泡以及高内皮静脉,其结构与其他粘膜相关淋巴组织相似。研究结果表明,分布于法氏囊柄部的淋巴组织是一种粘膜相关淋巴组织。  相似文献   

12.
【目的】原核表达斑马鱼(Danio rerio)蛋白酪氨酸磷酸酶受体B(PTPRB)并制备多克隆抗体,为研究斑马鱼PTPRB基因功能及血管发育相关信号传导通路打下基础。【方法】采用无缝克隆技术将斑马鱼PTPRB基因插入原核表达载体pET-B2m构建重组表达质粒,转化大肠杆菌B21感受态细胞后采用IPTG进行诱导表达,然后以诱导表达的融合蛋白免疫大耳兔制备多克隆抗体,并采用Western blotting和ELISA检测多克隆抗体的特异性及免疫效价。【结果】斑马鱼PTPRB蛋白亲水性均值为-0.490,属于亲水性蛋白,且具有较丰富的潜在抗原表位位点,分布均匀,无典型的跨膜区。将斑马鱼PTPRB基因插入原核表达载体pET-B2m成功构建获得重组表达质粒pET-B2-PTPRB,转化B21感受态细胞后经IPTG诱导表达,即获得35.0 kD的融合蛋白。融合蛋白PTPRB主要以包涵体形式存在;以纯化融合蛋白PTPRB免疫大耳兔,其血清抗体效价为1∶2048000,说明采用融合蛋白PTPRB可有效刺激大耳兔产生较强的免疫反应,获得较高效价的PTPRB多克隆抗体。Western blotting检测结果显示,PTPRB多克隆抗体具良好抗原特异性。采用Protein A/G亲和层析柱对制备获得的PTPRB多克隆抗体进行亲和层析纯化,可获得高纯度的多克隆抗体,纯化后的PTPRB多克隆抗体浓度在10 mg/mL以上。【结论】构建的斑马鱼PTPRB基因原核表达载体能高效表达具备良好免疫原性的融合蛋白PTPRB,以融合蛋白PTPRB免疫大耳兔可获得高效价、高特异性的PTPRB多克隆抗体,为研究斑马鱼PTPRB蛋白功能提供有利工具,也为揭示PTPRB在鱼类血管发育中的作用机制提供技术支持。  相似文献   

13.
Lymphocytes are essential mediators of normal tissue inflammatory reactions and of pathologic tissue damage in, for example, rheumatoid arthritis and other autoimmune diseases. In a study of the mechanisms controlling lymphocyte entry into sites of inflammation from the blood, the function and specificity of lymphocyte-endothelial interactions were examined in inflamed joint tissue (synovium) from patients with rheumatoid arthritis. Synovial high endothelial venules (HEV) supported the binding of normal peripheral blood lymphocytes in vitro. The characteristics of this binding, which were similar to those of lymphocyte-HEV interactions controlling lymphocyte migration into organized lymphoid tissues, included a requirement for calcium ions, a dependence on metabolic activity, and a preferential adherence of circulating lymphocytes as opposed to immature thymocytes. However, the binding of lymphocytes to synovial HEV was not inhibited by a monoclonal antibody to lymphocyte receptors for lymph node HEV, and synovial HEV failed to bind either lymph node HEV-specific or mucosal HEV-specific B lymphoblastoid cells. The results suggest that a lymphocyte-endothelial cell recognition system that is distinct from such systems in organized lymphoid tissues directs the extravasation of normal lymphocytes as well as pathologically important effector cells into inflamed synovium.  相似文献   

14.
Lymphocyte egress from the thymus and from peripheral lymphoid organs depends on sphingosine 1-phosphate (S1P) receptor-1 and is thought to occur in response to circulatory S1P. However, the existence of an S1P gradient between lymphoid organs and blood or lymph has not been established. To further define egress requirements, we addressed why treatment with the food colorant 2-acetyl-4-tetrahydroxybutylimidazole (THI) induces lymphopenia. We found that S1P abundance in lymphoid tissues of mice is normally low but increases more than 100-fold after THI treatment and that this treatment inhibits the S1P-degrading enzyme S1P lyase. We conclude that lymphocyte egress is mediated by S1P gradients that are established by S1P lyase activity and that the lyase may represent a novel immunosuppressant drug target.  相似文献   

15.
为研究圆小囊在家兔球虫感染后的病理变化,试验收集自然感染病例的圆小囊,按HE染色石蜡切片方法制作病理组织切片,观察自然感染球虫后家兔圆小囊的组织病理学变化,并与正常圆小囊组织进行比较。结果表明,球虫感染病例的圆小囊集合淋巴小结生发中心反应活跃,粘膜杯状细胞和固有层散在淋巴细胞明显增多,淋巴小结周边及中心多见吞噬细胞成团聚集,或形成大的多核巨细胞,而集合淋巴小结结构基本完整.该研究结果说明圆小囊的局部免疫机制可能在机体抗球虫免疫中起着重要作用。  相似文献   

16.
The chemokines CCL21 and CXCL13 are immune factors that dictate homing and motility of lymphocytes and dendritic cells in lymphoid tissues. However, the means by which these chemokines are regulated and how they influence cell trafficking during immune responses remain unclear. We show that CCL21 and CXCL13 are transiently down-regulated within lymphoid tissues during immune responses by a mechanism controlled by the cytokine interferon-gamma. This modulation was found to alter the localization of lymphocytes and dendritic cells within responding lymphoid tissues. As a consequence, priming of T cell responses to a second distinct pathogen after chemokine modulation became impaired. We propose that this transient chemokine modulation may help orchestrate local cellularity, thus minimizing competition for space and resources in activated lymphoid tissues.  相似文献   

17.
In the presence of 10(-4) to 10(-5) molar adenosine, established cell lines of fibroblastic or lymphoid origin die of pyrimidine starvation. Less than lethal concentrations inhibit cell growth. Over a broad concentration range, the effects of adenosine are prevented by providing a suitable pyrimidine source. We suggest that the recently described immune deficiency disease associated with absence of adenosine deaminase may be the result of pyrimidine starvation induced by adenosine nucleotides in cells of the lymphoid system.  相似文献   

18.
Chemokine receptors serve as portals of entry for certain intracellular pathogens, most notably human immunodeficiency virus (HIV). Myxoma virus is a member of the poxvirus family that induces a lethal systemic disease in rabbits, but no poxvirus receptor has ever been defined. Rodent fibroblasts (3T3) that cannot be infected with myxoma virus could be made fully permissive for myxoma virus infection by expression of any one of several human chemokine receptors, including CCR1, CCR5, and CXCR4. Conversely, infection of 3T3-CCR5 cells can be inhibited by RANTES, anti-CCR5 polyclonal antibody, or herbimycin A but not by monoclonal antibodies that block HIV-1 infection or by pertussis toxin. These findings suggest that poxviruses, like HIV, are able to use chemokine receptors to infect specific cell subtypes, notably migratory leukocytes, but that their mechanisms of receptor interactions are distinct.  相似文献   

19.
A secretory immune response to the carcinogen 2-acetylaminofluorene (AAF) was elicited in rabbits by directly immunizing the small intestine with an AAF-cholera toxin conjugate. High-titer, high-affinity secretory immunoglobulin A (IgA) antibody to AAF was secreted into the intestinal lumen in response to this immunogen. Immune secretions reduced the transepithelial absorption of a 125I-labeled derivative of AAF by more than half. This reduction of absorption by hapten-specific IgA suggests that oral vaccines against carcinogens and toxicants could be developed for humans.  相似文献   

20.
Anti-idiotypic antibodies bear the internal image of a human tumor antigen   总被引:6,自引:0,他引:6  
Goat antibodies to idiotypes (anti-idiotypic antibodies; Ab2) that recognize an idiotype associated with the combining site of a BALB/c mouse IgG2a monoclonal antibody (Ab1) to human gastric carcinoma were used to immunize BALB/c mice and rabbits. A monoclonal anti-anti-idiotypic antibody (Ab3) of IgG1 isotype was obtained after immunization of mice. The Ab3 and the Ab1 showed identical binding specificities and bound with similar avidities to the same tumor antigen. The induction of Ab1-like Ab3 by Ab2 was not restricted to mice, since Ab3 could also be induced in rabbits. Both the mouse- and the rabbit-derived Ab3 bound the same gastrointestinal cancer-associated antigen as Ab1. These findings indicate that Ab2 induced the formation of antigen-specific Ab3, probably because it bears the internal image of the tumor-associated antigen. This Ab2 may therefore have potential for modulating the immune response of cancer patients to their tumors.  相似文献   

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