首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 140 毫秒
1.
Large numbers of eosinophils and neutrophils attracted to the soluble extract of Schistosoma japonicum adult worms (SjAW-ext) were detected at the injection site of normal guinea pig skin. Eosinophil and neutrophil chemotactic activities were also confirmed in in vitro assay by using blind-well chambers with Millipore filters in dose-dependent fashion. Two components of SjAW-ext showed eosinophil chemotactic activity; one was in the high molecular weight fraction (JAE-H), estimated to be more than 440,000 daltons, the other in the low molecular weight fraction (JAE-L) obtained by Sephadex G-200 gel filtration. High neutrophil chemotactic activity was detected in the JAE-L. These eosinophil and neutrophil chemotactic activities were also detected in culture fluid of S. japonicum adult worms. Eosinophil chemotactic factor (ECF) of JAE-H was stable to heating (100 C, 30 min) and pronase digestion, but completely destroyed by periodate oxidation. It is suggested that the ECF of JAE-H is a glycoprotein. JAE-L was also stable to heating (56 and 100 C, 30 min) and pronase digestion for eosinophil chemotaxis. Possible roles of those activities in schistosome infections are discussed.  相似文献   

2.
Two neutrophil chemotactic factors were identified in soluble egg antigen preparations of Schistosoma japonicum. The higher-molecular-weight neutrophil chemotactic factor was not separable from eosinophil chemotactic factor by means of gel filtration, anion-exchange chromatography, isoelectric focusing, or affinity chromatography; this neutrophil chemotactic factor is apparently identical to the higher-molecular-weight eosinophil chemotactic factor which we purified previously from the soluble egg antigen. The chemotactic activity of the eosinophil chemotactic factor for neutrophils was stable to periodate oxidation but was notably affected by heating or Pronase digestion, suggesting that the determinant for neutrophil chemotaxis exists on the peptide moiety of the eosinophil chemotactic factor. The lower-molecular-weight neutrophil chemotactic factor was separable from the higher-molecular-weight eosinophil chemotactic factor by gel filtration or anion-exchange chromatography. This neutrophil chemotactic factor was rather hydrophobic and heat-stable, but was sensitive to Pronase or carboxypeptidase A digestion. These results suggest that the receptors on the surfaces of neutrophils and eosinophils for those chemoattractants would be different from each other. We suppose that neutrophil chemotactic factors and eosinophil chemotactic factors from the eggs are responsible for neutrophil and eosinophil accumulation around the eggs in schistosomiasis japonica.  相似文献   

3.
An eosinophil chemotactic factor (ECF) can be released from human polymorphonuclear neutrophils (PMN) and rat mast cells by the calcium ionophore A23187, during phagocytosis, by arachidonic acid and melittin. It has been suggested that these stimuli lead to phospholipid turnover with the generation of arachidonic acid, which is subsequently transformed by a converting enzyme to ECF. Addition of polienoic (5,8,11-eicosatrienoic and 4,7,10,13-eicosatetraenoic acids) or poliynoic acids (5,8,11-eicosatriynoic and 4,7,10,13-eicosatetraynoic acids) induced a dose- and time-dependent inhibition of ECF release from the cells. Poliynoic acids are more potent inhibitors than polienoic acids. Among the former 4,7,10,13-eicosatetraynoic acid is the most effective substance.  相似文献   

4.
Delayed tissue eosinophilia in DNP-ovalbumin-induced allergic inflammatory skin lesions of guinea pigs was markedly enhanced by previous treatment with alum hydroxy gel (Alum) or Bordetella pertussis vaccine. This enhancement seemed due to increased production of a lymphocyte-derived eosinophil chemotactic factor (ECF) at the skin site. Treatment of animals with Alum potentiated antigen-induced in vitro ECF production by lymphoid cells from spleen and mesenteric lymph node of sensitized animals. The co-culture supernatants of lymphoid cells from Alum-treated animals also potentiated concanavalin A (Con A)-induced in vitro ECF production. The potentiating effect of Alum on ECF production seemed to be ascribed to the release of soluble factors from macrophages of the Alum-treated animals. The macrophage-derived soluble factor ECF-potentiating factor (ECF-PF) selectively potentiated ECF production but not macrophage chemotactic lymphokine production by Con A-stimulated lymphoid cells from normal animals. ECF-PF activity was associated with two separate m.w. fractions: one was 50,000 to 70,000 and the other was 10,000 to 20,000. The present study provides one of the explanations for enhanced ECF production by adjuvants, such as Alum and Bordetella pertussis vaccine.  相似文献   

5.
An acidic peptide, preferentially chemotactic for eosinophils, was extracted from livers of mice infected with Schistosoma mansoni. Sephadex G-25 column chromatography showed that the majority of the eosinophil chemotactic activity was detected in the fractions just after elution of the molecular marker vitamin B12 (m.w. 1355.4). This activity began to appear in the livers of some mice 5 weeks after infection. Peak activity was detected at 8 to 12 weeks after infection and persisted at least until 16 weeks. It was sensitive to carboxypeptidase-A. By Dowex-1 anion exchange chromatography, the activity eluted as a narrow peak at pH 3.1 TO 2.6 as shown for eosinophil chemotactic factor of anaphylaxis (ECF-A). The activity was also detected in a broad peak at pH 6.3 to 3.7. Unlike ECF-A, the activity was stable to boiling in both acid and alkali. These findings suggest that granulomatous liver of murine schistosomiasis-derived eosinophil chemotactic factor (ECF-G) may play a specific role in eosinophil accumulation in this chronic inflammation.  相似文献   

6.
Differences between the conditions for an eosinophil chemotactic factor (ECF) and macrophage chemotactic factor (MCF) production by lymphoid cells of mesenteric lymph nodes and spleen were studied in guinea pigs. If lymphoid cells were washed less than 4 hr after concanavalin A (Con A) stimulation and were cultured for an additional 24 hr, they failed to produce ECF, whereas Con A stimulation for 1 hr before washing was sufficient to stimulate them to produce MCF. Subsequently, it was shown that heat-labile soluble factors (termed ECF-PF) with potentiating activity for ECF production are produced from macrophages by 5 micrograms/ml Con A activation. When ECF-PF were added to the cell culture with 5 micrograms/ml Con A, the lymphoid cells could produce ECF even when they were washed 2 hr after Con A stimulation and were cultured for an additional 24 hr, suggesting that ECF-PF plays a critical role in the early stage of ECF production. The lymphoid cells were also able to produce ECF even when they were cultured with ECF-PF and a suboptimal dose of Con A (1 microgram/ml) for ECF production. Protein synthesis seemed to be essential for ECF-PF production. The ECF-PF activity was associated with two separated molecular fractions with m.w. of about 50,000 to 70,000 and of 10,000 to 20,000. It is thus suggested that ECF is produced from T cells by Con A stimulation under conditions which differ, at least, from those for MCF in the requirement of ECF-PF.  相似文献   

7.
When guinea pigs were treated by complete Freund's adjuvant (CFA), eosinophil-directed chemotactic inhibitory factor (ECIF) appeared in the serum of the treated animals. The inhibition of the response of eosinophils by ECIF was selective for the T cell-derived chemotactic factor, which has been isolated from DNP-ascaris extract-induced skin lesions (termed delayed ECF-a) but not for another ECF (termed delayed ECF-b), which was also isolated from the same skin lesions. ECIF was detected in the serum after a single CFA injection, and no significant increase of ECIF activity was observed in the serum of animals injected with CFA twice. The ECIF activity in the serum was associated with fractions of MW 70,000 and 12,500, and failed to bind to Con A-Sepharose. Furthermore, ECIF was absorbed by eosinophils but not by macrophages suggesting that eosinophils have receptor sites for ECIF. On the other hand, chemotactic inhibitor against delayed ECF-b was not detected in the serum. It was thus suggested that inhibition of eosinophil reaction by CFA treatment is related to ECIF, inhibition being selective for the eosinophil response to delayed ECF-a.  相似文献   

8.
Tissue eosinophilia is often found in the inflammatory lesions of bullous perphigoid. A study made on naturally occurring eosinophil chemotactic activity in the blister fluids of four bullous pemphigoid patients revealed the existence of this activity in all of them. Sephadex G-25 column chromatography showed that the greater part of this eosinophil chemotactic activity was composed of low molecular substance of which the weight was close to that of vitamin B12 (m.w. 1357). The blister fluids and the sera of these patients contained elevated levels of IgE. An IgE anti-skin basement, membrane antibody was found in two if the four sera, and deposits of IgE were detected along the basement membrane zone of the involved skin in one of the patients. On the basis of these findings, we have reason to believe that an eosinophil chemotactic factor of anaphylaxis (ECF-A) participates in the accumulation of eosinophils in the lesions of bullous pemphigoid.  相似文献   

9.
A novel eosinophil chemotactic cytokine (ECF-L) was purified from the culture supernatant of splenocytes of mice by a combination of anion-exchange chromatography, Procion red-agarose affinity chromatography, size exclusion high performance liquid chromatography (HPLC), and reverse phase HPLC. The NH(2)-terminal amino acid sequence was determined by direct protein sequencing. An ECF-L cDNA clone of 1,506 nucleotides was isolated from a cDNA library, and the nucleotide sequence predicted a mature protein of 397 amino acids. A recombinant ECF-L showed a level of eosinophil chemotactic activity comparable with that of natural ECF-L, and the activity was inhibited by a monoclonal antibody to ECF-L. ECF-L also attracted T lymphocytes and bone marrow polymorphonuclear leukocytes in vitro, whereas it caused selective extravasation of eosinophils in vivo. ECF-L mRNA was highly expressed in spleen, bone marrow, lung, and heart. A comprehensive GenBank data base search revealed that ECF-L is a chitinase family protein. ECF-L retains those amino acids highly conserved among chitinase family proteins, but Asp and Glu residues essential for the proton donation in hydrolysis were replaced by Asn and Gln, respectively. Although ECF-L contains a consensus CXC sequence near the NH(2) terminus akin to chemokine family proteins, the rest of ECF-L shows poor homology with chemokines.  相似文献   

10.
A high m.w. eosinophil chemotactic factor (ECF-SjE) was isolated and purified from a soluble egg antigen preparation (SEA) of Schistosoma japonicum by gel filtration on Sephacryl S-200, anion-exchange chromatography on DE52, and isoelectric focusing. ECF-SjE had a m.w. of more than 900,000 and an isoelectric point of 4.1. It contained 40% (w/w) sugar residues and bound to concanavalin A (Con A). The chemotactic activity of ECF-SjE was heat stable (100 degrees C, 60 min) and resistant to pronase digestion, but was destroyed by periodate oxidation. IgG antibody to ECF-SjE was detected in the serum of a rabbit infected with S. japonicum, demonstrating the antigenic nature of ECF-SjE. The antigenicity of ECF-SjE was also sensitive to periodate oxidation. Thus, ECF-SjE is a glycoprotein or proteoglycan from the eggs of S. japonicum, and the sugar chain is important for the expression of chemotactic and antigenic activities. However ECF-SjE differs from the major allergenic components of S. japonicum (JEAL) in m.w. and isoelectric point. A low m.w. eosinophil chemotactic factor was also detected in SEA. Together they are proposed to have a role in the direct accumulation of eosinophils in the egg-induced granulomas in S. japonicum infection.  相似文献   

11.
Neutrophil chemotaxis is a process that is essential for the recruitment of neutrophils to an inflamed site. In the present study, we found a remarkable increase in neutrophil chemotactic activity in the lysate of red blood cells (RBC) of mice infected with murine malaria, Plasmodium yoelii. A neutrophil chemotactic factor with an apparent molecular weight of 17 kDa (IP17) was isolated from RBC by a combination of anion-exchange chromatography on DE52 and cation-exchange chromatography on Mono S. A comprehensive GenBank database search of N-terminal amino acid sequences and MALDI-TOF mass analysis of IP17 revealed that IP17 is identical to a murine homologue of ISG15/UCRP, a member of the ubiquitin family of proteins that are inducible by interferon-beta. Recombinant mouse ISG15 showed neutrophil chemotactic activity comparable to that of natural IP17. IP17 showed specific chemotactic activity forward neutrophils and activated neutrophils to induce the release of eosinophil chemotactic factors. These results suggest that the ubiquitin family protein ISG15/UCRP has novel functions in neutrophil-mediated immune mechanisms.  相似文献   

12.
Highly purified eosinophils were obtained from normal subjects, and their chemotactic responses to platelet activating factor (PAF) were evaluated. PAF induced both eosinophil chemotactic and chemokinetic responses, and was 100 fold more potent eosinophil chemotactic factor as compared to eosinophil chemotactic factor of anaphylaxis. On the other hand, leukotriene B4 did not show any eosinophil chemotactic activity. A selective PAF antagonist, BN52021, inhibited eosinophil chemotaxis in a dose dependent manner. Preincubation of eosinophils with PAF induced the deactivation of eosinophils for further chemotactic responses to PAF. These findings suggest that PAF is a potent chemotactic factor for normal eosinophils.  相似文献   

13.
The infective (third stage) larva of Ostertagia ostertagi produced an excretory secretory substance that is chemotactic for bovine eosinophils. The eosinophil chemotactic substance was present in supernatants of larval cultures within 6 hr of incubation in Eagle's Minimum Essential Medium containing 25 mM N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid. The substance responsible for eosinophil chemotaxis has activity in small amounts, a molecular weight (MW) greater than 2000, and is heat labile at 100 C. Bovine eosinophils appeared to have a receptor for the chemotactic excretory secretory substance which is either identical or structurally similar to the previously described eosinophil chemotactic substance present in soluble third stage larval extracts. The larval substance may cause eosinophil accumulation in the abomasal tissue of cattle with ostertagiasis.  相似文献   

14.
Leukocyte chemotactic activity of cyclophilin.   总被引:14,自引:0,他引:14  
During the purification of eosinophil chemotactic factors synthesized by the uterus in response to estrogen we isolated a protein having an N-terminal (15 amino acids) sequence identical to that of rat cyclophilin. Our data demonstrate that cyclophilin, a cytosolic protein isolated from bovine thymocytes, which specifically binds the immunosuppressive drug cyclosporin A, as well as recombinant human cyclophilin, displays eosinophil chemotactic activity. In addition to its chemotactic activity, cyclophilin stimulated the release of peroxidase activity from eosinophils. Maximal chemotactic activity of cyclophilin was achieved at a concentration of approximately 10 nM. At similar concentrations cyclophilin was also able to stimulate the migration of neutrophils. This chemotactic activity could be prevented by the addition of cyclosporin A, but not by a nonimmunosuppressive analog (1-fur-furyl-cyclosporin A) at similar concentrations. This chemotactic activity may represent an additional mechanism by which immunosuppressive drugs function to prevent tissue rejection.  相似文献   

15.
Eosinophil chemotactic activity associated with protein extracts of Taenia taeniaeformis metacestodes was investigated. Chemotactic activity was associated with the nonbound protein after QAE cellulose chromatography of a 3 M KCl extract of homogenized larvae. When this material was precipitated with ammonium sulfate, activity was present in the 40 to 80% precipitate. Upon rechromatography on QAE cellulose equilibrated in a low ionic strength buffer, eosinophil chemotactic activity was retained by the gel and eluted after application of the NaCl gradient. Gel filtration of Sephacryl S-300 yielded an estimated m.w. of 91,000. Chromatofocusing revealed a broad peak of activity with a pI of 4.5 to 5.0. SDS-PAGE showed the active fraction migrated as a protein with a m.w. of 10,400. ECF-Tt had chemotactic and chemokinetic activity for equine eosinophils and murine eosinophils, but not for equine and murine neutrophils.  相似文献   

16.
Recently our laboratory has shown that neutrophils contain enzymatic activity within their lysosomal granules which will generate chemotactic activity for neutrophils and tumor cells from the fifth component of complement (C5). We have now expanded this initial observation and have demonstrated that eosinophils can release enzymatic activity from their lysosomal granules upon stimulation with immune complexes or opsoninized zymosan, but not with C5a or synthetic chemotactic peptides. Furthermore, the enzymatic activity released from the eosinophil lysosomal granules can cleave C5 into eosinophil-specific chemotactic activity. The generation of the eosinophil chemotactic activities from C5 is blocked by prior treatment of the eosinophil preparations with a number of protease inhibitors. The eosinophil-derived C5 cleaving activity possesses a pH optimum of 7.2, thus suggesting the enzymatic activity is a neutral protease. The demonstration that enzyme activities derived from eosinophils have the ability to generate eosinophil chemotactic factor(s) from C5 may explain why eosinophils are the predominant inflammatory cell in both nasal polyps and in the nasopharynx and bronchi of patients with allergic conditions such as hay fever and asthma.  相似文献   

17.
A gene encoding the manganese superoxide dismutase (Mn-SOD) of Spirometra erinacei was identified, and the biochemical properties of the recombinant enzyme were partially characterized. The S. erinacei Mn-SOD gene consisted of 669 bp, which encoded 222 amino acids. A sequence analysis of the gene showed that it had typical molecular structures, including characteristic metal-binding residues and motifs that were conserved in Mn-SODs. An analysis of the N-terminal presequence of S. erinacei Mn-SOD revealed that it had physiochemical characteristics commonly found in mitochondria-targeting sequences and predicted that the enzyme is located in the mitochondria. A biochemical analysis also revealed that the enzyme is a typical Mn-SOD. The enzyme was consistently expressed in both S. erinacei plerocercoid larvae and adult worms. Our results collectively suggested that S. erinacei Mn-SOD is a typical mitochondrial Mn-SOD and may play an important role in parasite physiology, detoxifying excess superoxide radicals generated in the mitochondria.  相似文献   

18.
The chemotactic response of mouse eosinophil-rich peritoneal exudative cells to the lymphokine eosinophil stimulation promoter (ESP) was examined. Both eosinophils and monocytes are chemotactically attracted across a 3-μm-pore size polycarbonate filter toward a concentration gradient of ESP-containing culture supernatant fluids. Deactivation of both cell types occurs following preincubation of the responding cells in culture supernates containing ESP activity. The chemotactic activity for both eosinophils and mononuclear cells is stable when incubated at 60 °C for 30 min but is labile at 80 °C, is nondialyzable, and at peak activity exhibits an apparent molecular weight of approximately 25,700 daltons, based on Sephadex G-100 gel chromatography. Production conditions required for the generation of chemotactic and ESP activities are identical, and fractions of culture supernatant fluids possessing one activity are also positive for the other. Preliminary results therefore indicate that the lymphokine ESP attracts both eosinophils and monocytes in a gradient-induced chemotaxis assay.  相似文献   

19.
Eosinophils immunopositive for bombesin tetradecapeptide were detected by means of light and electron microscopy in human and rat gastrointestinal tract and pulmonary tissue. This immunoreaction was only evidenced after the use of acetic acid-containing fixative such as Bouin's fluid. The dependence of this immunostaining on fixatives and time course were extensively studied. This immunoreaction promotes mainly one epitope probably associated with the C-terminal sequence. This epitope seems also to be present in other neuropeptides such as substance P (SP) and, to a lesser extent in chemotactic factors like formyl peptide (fMLP) or eosinophil chemotactic factor of anaphylaxis (ECF-A). At the electron microscopic level, the immunopositivity was associated with eosinophil membranes.  相似文献   

20.
Preincubation of eosinophils with 10(-5) M or higher concentrations of histamine inhibited the eosinophil chemotactic response to endotoxin-activated serum whether by using the nucleopore filter assay and counting the cells migrating through the filter, or by using the Zigmond-Hirsch assay and counting the cells at each 10-mum interval. When the H2-receptor sites on the eosinophils were blocked by metiamide, the inhibitory capacity of histamine was prevented. Preincubation of eosinophils with 10(-6) M histamine increased the number of responding eosinophils to endotoxin-activated serum and this enhancement was blocked by an H1-receptor antagonist. Isoproteronol and aminophylline inhibited eosinophil movement and increasing concentrations of dibutryl cyclic AMP inhibited eosinophil migration. Concentrations of histamine that consistently resulted in inhibition of eosinophil movement stimulated an increase in cyclic AMP that was prevented by blocking the H2-receptor but not the H1-receptor. Thus, histamine-dependent inhibition of the eosinophil chemotactic response to other agents is mediated through the H2-receptor and is associated with an increase in the intracellular level of cyclic AMP whereas histamine dependent enhancement of eosinophil migration to other agents appears to be mediated through the H1-receptor. Eosinophils behave as a heterogeneous population as assessed by the ability of histamine to augment or inhibit cell migration. This may reflect differences in H1 to H2 receptor density or cell responsiveness to receptor stimulation. The chemoattractant activity of histamine itself is not influenced by H1 or H2 receptor antagonists, thus it is possible that an eosinophil has a third type of histamine receptor.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号