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1.
The axial organ (AO-cells) of the sea star Asterias rubens is a primitive immune organ. The total population was fractionated or not into two populations: adherent (B-like) and non adherent (T-like) to nylon wool. Rabbit anti sea star lymphocyte serum induces the proliferation of axial organ cells. The T-like antiserum stimulates the T-like cells exclusively; the whole axial organ cell antiserum only stimulates the whole axial organ cell population.  相似文献   

2.
The axial organ (A.O. cells) of the sea star Asterias rubens is a primitive immune organ. The total population was fractionated into two populations: adherent (B-like) and non-adherent (T-like) to nylon wool. The adherent cells resemble mammalian B lymphocytes and bear homologous human T cell receptor (beta chain) to a higher degree than T-like cells which resemble T lymphocytes.  相似文献   

3.
Axial organ cells from the sea star (Asterias rubens) inoculated 7 days before with TNP- or FITC-haptenated PAA beads and subsequently stimulated in vitro with the same antigen, produced and released a specific, soluble "antibody-like" substance that induced lysis of haptenated sheep erythrocytes. Fresh normal rabbit or guinea pig serum was essential for the lysis, suggesting the participation of complement components. The factor was produced by the total population of axial organ cells but not by nylon-wool adherent (B-like) or nonadherent (T-like) cells. These results provide further evidence of the existence, in the sea star, of a primitive immune system with characteristics reminiscent of the immune system of vertebrates.  相似文献   

4.
Tissue sections of lymph nodes, appendices and tonsils, together with smears of immunologically separated peripheral lymphoid cells from a B-CLL and lymphomatous cells from an immunocytoma were submitted to combined enzyme cytochemical investigations with acid alpha-naphthyl acetate esterase (ANAE), beta-glucuronidase (B-G), acid phosphatase (AcPh), adenosine triphosphatase (ATPase), a,d 5'nucleotidase (5'N). T-cells were Acph+, ATPase- and 5'N-. The vast majority of T- and B-cells displayed ANAE and B-G activities with two distinct staining patterns (T-like and B-like pattern). A high proportion of lymphoid cells in the germinal centre (G.C.) and the vast majority of lymphoid cells in the mantle-zone (M.Z.) were shown to belong to B-cell system because of the expression of ATPase and 5'N in their membranes. Some lymphoid cells positive for ANAE and B-G with a B-like pattern and for AcPh were recognizable in the G.C. In the M.Z. only a few lymphoid cells being ANAE+, with a T-like pattern, and AcPh+ were shown to belong to the T-cell system. In contrast, in this zone a high proportion of small lymphoid cells (64% +/- 10%) showed ANAE activity, mostly with B-like pattern. Therefore, these findings indicate that in the M.Z. a high proportion of B-cells ATPase+ and 5'N+ also display ANAE activity. By comparison of the results obtained from lymphoid tissue sections, B-CLL and immunocytoma cell suspensions and normal circulating lymphocytes we can conclude that B-ANAE-positive cells of the M.Z. do not usually appear in the peripheral blood. They circulate in large numbers only in some pathological conditions (like our reported B-CLL). Therefore, B-ANAE-positive lymphoid cells of the mantle, with a B-like staining pattern, include a wide range of subsets which exclude large lymphoid cells and plasma cells.  相似文献   

5.
The study of immune related genes in lampreys and hagfish provides a unique perspective on the evolutionary genetic underpinnings of adaptive immunity and the evolution of vertebrate genomes. Separated from their jawed cousins at the stem of the vertebrate lineage, these jawless vertebrates have many of the gene families and gene regulatory networks associated with the defining morphological and physiological features of vertebrates. These include genes vital for innate immunity, inflammation, wound healing, protein degradation, and the development, signaling and trafficking of lymphocytes. Jawless vertebrates recognize antigen by using leucine-rich repeat (LRR) based variable lymphocyte receptors (VLRs), which are very different from the immunoglobulin (Ig) based T cell receptor (TCR) and B cell receptor (BCR) used for antigen recognition by jawed vertebrates. The somatically constructed VLR genes are expressed in monoallelic fashion by T-like and B-like lymphocytes. Jawless and jawed vertebrates thus share many of the genes that provide the molecular infrastructure and physiological context for adaptive immune responses, yet use entirely different genes and mechanisms of combinatorial assembly to generate diverse repertoires of antigen recognition receptors.  相似文献   

6.
7.
A small but definite proportion of T-lymphocyte-like cells have been reported in nu/nu (nude) mouse spleen despite the congenital absence of a thymus in these animals. We have determined the number and the characteristics of such cells using flow cytometry. The level of T-like cells increased with age. In 4-month-old nu/nu CBA spleen, 14% of all cells expressed some Thy 1 antigen. However, only 4% expressed mature T-cell levels, and only the 2% with the highest Thy 1 also showed a normal distribution of Ly 1 and Ly 2 antigens. These T-like cells were slightly larger than normal nondividing T lymphocytes. We have assessed the total functional capacity of T-like cells in nu/nu CBA spleen using a high-cloning-efficiency limit-dilution culture system. Almost all precursor cells capable of forming clones when stimulated with concanavalin A in the presence of irradiated spleen cells and growth factors, and almost all precursors of those clones that were cytolytic in a lectin-mediated tumor-cell-lysis assay, were within this 2% subpopulation of nu/nu spleen cells with mature T-cell markers. Increased levels of purified interleukin 2 failed to induce further precursor function, indicating that maturation of pre-T cells was not obtained. However the nu/nu spleen cells bearing mature T-cell markers displayed only 10-30% of the cloning efficiency of normal splenic T cells. The majority of nu/nu spleen T-like cells, even within this phenotypically "normal" subset, appeared to be nonfunctional. We conclude that the absence of a thymus leads to qualitative, as well as quantitative, deficiencies in the T-cell population, and various interpretations are discussed.  相似文献   

8.
The axial organ of the sea star Asterias rubens is a primitive immune organ. In addition to T and B-like cells phagocytic cells were also identified. In this report we demonstrate that these cells can be identified using immunocytochemistry together with the mouse to human monoclonal antibody CD68 KP1, normally used as a macrophage marker.  相似文献   

9.
Human alpha-nitrosyl beta-deoxy hemoglobin A, alpha(NO)beta(deoxy), is considered to have a T (tense) structure with the low O(2) affinity extreme and the Fe-histidine (His87) (Fe-His) bond of alpha heme cleaved. The Fe-His bonding of alpha heme and the intersubunit interactions at the alpha 1-beta 2 contact of alpha(NO)-Hbs have been examined under various conditions with EPR and UV resonance Raman (UVRR) spectra excited at 235 nm, respectively. NOHb at pH 6.7 gave the UVRR spectrum of the R structure, but in the presence of inositol-hexakis-phosphate (IHP) for which the Fe-His bond of the alpha heme is broken, UVRR bands of Trp residues behaved half-T-like while Tyr bands remained R-like. The half-ligated nitrosylHb, alpha(NO)beta(deoxy), in the presence of IHP at pH 5.6, gave T-like UVRR spectra for both Tyr and Trp, but binding of CO to its beta heme (alpha(NO)beta(CO)) changed the UVRR spectrum to half-T-like. Binding of NO to its beta heme (NOHb) changed the UVRR spectrum to 70% T-type for Trp but almost R-type for Tyr. When the pH was raised to 8.2 in the presence of IHP, the UVRR spectrum of NOHb was the same as that of COHb. EPR spectra of these Hbs indicated that the Fe-His bond of alpha(NO) heme is partially cleaved. On the other hand, the UVRR spectra of alpha(NO)beta(deoxy) in the absence of IHP at pH 8.8 showed the T-like UVRR spectrum, but the EPR spectrum indicated that 40-50% of the Fe-His bond of alpha hemes was intact. Therefore, it became evident that there is a qualitative correlation between the cleavage of the Fe-His bond of alpha heme and T-like contact of Trp-beta 37. We note that the behaviors of Tyr and Trp residues at the alpha 1-beta 2 interface are not synchronous. It is likely that the behaviors of Tyr residues are controlled by the ligation of beta heme through His-beta 92(F8)-->Val-beta 98(FG5)-->Asp-beta 99(G1 )-->Tyr-alpha 42(C7) or Tyr-beta 145(HC2).  相似文献   

10.
11.
成纤维细胞生长因子8 (fibroblast growth factor 8,FGF8)是成纤维细胞生长因子家族的成员之一,是一种组织发育过程中的重要分泌性调控信号分子,参与脊椎动物的多种组织器官的发生与发育.早期胚胎细胞通过表达FGF8在组织和器官发育、血管发生、血细胞生成、附肢发生和伤口愈合等方面发挥着重要作用.FGF8不但可以在细胞外通过胞内信号通路,而且也可以进入细胞内部发挥生物学功能.本文就FGF8在脊椎动物神经系统、内脏器官、肢体发育及不对称发育等组织、器官发育中的调控作用予以阐述.  相似文献   

12.
Phylogeny and ontogeny of fish leucocytes   总被引:8,自引:0,他引:8  
In contrast to higher vertebrates, most fish species hatch at the embryonic stage of life. Consequently, they have to defend against a variety of micro-organisms living in their aquatic environment. This paper is focussed on the development of leucocytes functioning within this early innate system and later on in the acquired immune system (B and T cells). Most of the data are derived from cyprinid fish (zebrafish, carp), which are excellent models to study early ontogeny. Attention is also paid to the phylogeny of leucocytes, with special attention to early chordates. It is clear that young fish use innate mechanisms during the first weeks/months of their development. In zebrafish, a variety of hematopoietic genes have been sequenced which allow a detailed picture of the development of the distinct leucocytes and their precursors. In cyprinids and sea bass, the thymus is the first lymphoid organ and T cells appear to be selected there much earlier than the first detection of T cell-dependent antibody responses. The first B cells are most probably generated in head kidney. Although T cells are selected earlier than B cells, T cell independent responses occur earlier than the T cell-dependent responses. The very early (pre-thymic) appearance of T-like cells in gut of sea bass and carp suggests an extra-thymic origin of these cells. However, B cells populate the GALT much later than spleen or kidney, indicating a rather late appearance of mucosal immunity. The first plasma cells are found long after the intake of food in cyprinids, but in many marine fish they appear around the first food intake. In general, acquired immunity is not correlated to food intake.  相似文献   

13.
A cathepsin B-like enzyme from the white muscle of common mackerel Scomber japonicus was a cysteine protease that hydrolyzed Z-Arg-Arg-MCA, the substrate for cathepsin B. In a partial purified cathepsin B-like enzyme preparation at 4 degrees C left over time, a converted enzyme that hydrolyzes Z-Arg-Arg-MCA and Z-Phe-Arg-MCA appeared in the preparation. The converted enzyme was purified from the cathepsin B-like enzyme, characterized and was identified as mackerel cathepsin B. These results suggested that the mackerel cathepsin B-like enzyme was a precursor of cathepsin B. Mackerel cathepsin B formed in the purified cathepsin B-like enzyme preparation by adding of a small amount of the purified cathepsin B to the preparation. Therefore, mackerel cathepsin B-like enzyme was converted to the mature form of cathepsin B by autoactivation. The conversion of the cathepsin B-like enzyme (molecular mass 60 kDa) to cathepsin B (molecular mass 23 kDa) was detected by immunoblotting by using human anti-(cathepsin B) antibody. The intermediate forms of 40 kDa and 38 kDa were also detected during the conversion.  相似文献   

14.
Recombinant tumor necrosis factor (TNF), epidermal growth factor (EGF), and transforming growth factor beta (TGF-beta) stimulated growth of confluent human diploid fibroblasts (FS-4 cells) in the presence of fetal calf serum. TGF-beta synergistically enhanced both the TNF- and EGF-stimulated cell growth, whereas synergism between the mitogenic action of EGF and that of TNF was not observed. When indomethacin or acetylsalicylic acid, an inhibitor of prostaglandin production, was added to FS-4 cells, cell growth stimulated by EGF or TNF was increased, suggesting that prostaglandins induced by these mitogens antagonize their growth stimulatory actions. In contrast, neither indomethacin nor acetylsalicylic acid had a significant effect on the TGF-beta-induced growth of FS-4 cells. Mitogenic responses of indomethacin-treated cells to EGF, TNF, and TGF-beta were similarly suppressed by the addition of exogenous prostaglandin D2 (PGD2). Other prostaglandins such as PGE2 and PGF2 produced less inhibition of the cell growth.  相似文献   

15.
Summary We show that silica enhances the proliferation of some but not all lung derived fibroblastlike cells (FLC) of fetal and adult origin. Cultures were obtained from lung biopsy and lavage of normal individuals and patients with interstitial lung disease. The responses of these cell lines were heterogenous; some cultures were stimulated to proliferate in the presence of silica and others were not stimulated. There was no apparent correlation between source of the cell lines and the effects of silica. The proliferative capacity of the cells appeared to be an important determinant of the effect of silica on the growth of the cultures. Supported by PHS 14212 Pulmonary SCOR Grant.  相似文献   

16.
长颖壳花器官突变体从野生稻(Oryza nivara Sharma et Shastry)和栽培稻(Oryza sativa subsp. indica Kato)杂交后代材料中获得。该突变体的内外稃变长、呈叶状,且顶端表现不同程度的开裂;每朵颖花的雄蕊1~10枚不等;雌蕊1~3枚不等;子房上柱头1~5个不等;有的颖花形成雄蕊/雌蕊嵌合体;子房处常附有瘤状物;此突变体结实率为18.2%;花粉可育率为62.46%。利用扫描电镜观察了该突变体花器官形态发生过程,并经遗传分析鉴定该突变性状由单隐性基因(暂命名为lh)控制。本文讨论了lh基因和以前鉴定的其他突变体基因之间的关系,通过表型分析推测,突变体基因可能影响花器官数目同时具有拟南芥B类基因的部分功能。  相似文献   

17.
Preliminary experiments show that rabbit anti sea star T-like serum recognizes T-like cells from two different geographic regions but not mouse T lymphocytes and man T lymphocytes. On the other hand, cytotoxicity reactions do not occur with this serum.  相似文献   

18.
酸性成纤维细胞生长因子(acid fibroblastgrowth factor,FGF-1)是成纤维细胞生长因子家族重要的成员之一。来源于三个胚层的细胞都能够表达FGF-1,其生物学效应非常广泛,在组织和器官发育、血管发生、血细胞生成、肿瘤发生和伤口愈合等方面发挥着重要作用。FGF-1不但可以在细胞外通过胞内信号通路而且也可以进入细胞内部发挥生物学功能。主要综述FGF-1信号转导方面的研究进展、促细胞增殖作用的可能分子机制以及将来的临床应用前景。  相似文献   

19.
Axial organ cells (A.O.) which are composed of phagocytes and lymphocytes from the sea star Asterias rubens exert a spontaneous cytotoxicity against mouse tumour cells. This toxicity was tested in the presence or absence of silica. It appears that phagocytes play the role of killer cells.  相似文献   

20.
Gu Z  Ma B  Jiang Y  Chen Z  Su X  Zhang H 《Gene》2008,415(1-2):1-12
Calcium plays a crucial role as a second messenger in mediating various defense responses under environmental stresses. Calcineurin B-like (CBL) proteins have been implicated as important Ca2+ sensors in plant-specific calcium signaling. Based on the similarity of sequence, ten CBL genes were identified by searching the rice japonica genome database, which were randomly distribute on chromosomes 1, 2, 3, 5, 10 and 12. By semi-quantitative RT-PCR approach the expression pattern of each gene was detected in various organs at the adult stage and seedlings treated with NaCl, PEG and cold stresses or exogenous ABA. The results showed that the induction of each rice CBL gene was not only responsive to different stress conditions, but also organ specific. In vivo targeting experiment revealed that OsCBL8 localized to the plasma membrane, which was consistent with OsCBL4 and SOS3 previously reported. To elucidate the putative function of OsCBL8 gene, transgenic rice plants overexpressing OsCBL8 gene were generated by the Agrobacterium-mediated approach. The OsCBL8 transgenic rice seedlings showed more tolerance to salt stress than non-transgenic seedlings.  相似文献   

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