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71.
Aging and the Immune Response to the Haemophilus influenzae Type b Capsular Polysaccharide: Retention of the Dominant Idiotype and Antibody Function in the Elderly
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Anti-Haemophilus influenzae b polysaccharide (Hib PS) antibodies elicited in elderly subjects following conjugate vaccination expressed a light-chain variable-region (VL)-associated idiotype and had functional activities similar to those previously observed in children and younger adults. These findings indicate that advanced age is not accompanied by shifts in the major VL component of the Hib PS-specific repertoire or by diminution of the protective function of antibodies. 相似文献
72.
A fucose-containing epitope potentially involved in gamete interaction on the human zona pellucida 总被引:2,自引:1,他引:2
Lucas H.; Bercegeay S.; Pendu J.Le; Jean M.; Mirallie S.; Barriere P. 《Human reproduction (Oxford, England)》1994,9(8):1532-1538
The oligosaccharide moiety of human, porcine and bovine zonaepellucidae was studied with lectins and monoclonal antibodiesspecific for tri- or tetra-saccharidic epitopes containing atleast one terminal -L-fucose. Animal eggs were collected fromfollicular aspirates, human eggs were collected from in-vitrofertilization and embryo transfer programmes and pooled intosix groups. By direct immunofluorescence, the lectins reactivitywas detected for the animal or the human zonae pools in thesame way. Reactivity of Aleuria aurantia lectin demonstratedthe presence of L-fucose terminal residues in the zonaefrom the three species studied. By indirect immunofluorescence,the 225 antibody reactivity was detected in every poolof human zonae whereas there was no evidence of any antibodyreactivity on animal zonae. Using an anti-Lewis-b blood groupantibody (225), we observed expression of this antigenas an intrinsic component of the human zona pellucida, independentlyof patients'Lewis red blood cell phenotypes. Antibody 225inhibited the spermatozoa-zona binding in a hemizonaassay, suggesting that this fucose-containing antigen couldbe part of a sperm-zona receptor. 相似文献
73.
H M Dockrell S K Young K Britton P J Brennan B Rivoire M F Waters S B Lucas F Shahid M Dojki T J Chiang Q Ehsan K P McAdam R Hussain 《Infection and immunity》1996,64(10):4385-4389
Twelve mycobacterial antigens were compared for induction of gamma interferon (IFN-gamma) secretion by human blood mononuclear cells of patients with leprosy. Fractionated Mycobacterium leprae antigens containing cell wall proteins or cytosolic and membrane proteins induced good IFN-gamma responses in tuberculoid leprosy patients. Lipoarabinomannan from M. tuberculosis Erdman and M. leprae mycolylarabinogalactan peptidoglycan were the poorest IFN-gamma inducers. 相似文献
74.
Cold-adapted vaccine strains of influenza A virus act as dominant negative mutants in mixed infections with wild-type influenza A virus 总被引:2,自引:0,他引:2
The cold-adapted reassortant of influenza A, which is a candidate live virus vaccine, interfered with the replication of parental wild-type virus in mixed infections of either MDCK cells or embryonated eggs. The interference occurred at either the permissive or nonpermissive temperature for the cold-adapted virus. In doubly infected cells, the yield of the wild-type virus was reduced by as much as 3000-fold and the protein synthesis phenotype expressed was that of the cold-adapted virus. The interference was detected even when infection with wild-type virus was carried out at a 9-fold excess or 2 hr before infection with the cold-adapted virus. As well as interfering with its wild-type parental virus, the cold-adapted virus also inhibited the replication of a heterologous influenza A subtype. In addition to its immunogenic potential, the ability to interfere with the replication of wild-type viruses is a desirable trait for any live, attenuated virus vaccine. 相似文献
75.
Correlation of proliferation of lung epithelium with intramuscular sensitization and complement-fixing antibody to respiratory syncytial virus in the golden hamster.
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H V Ratajczak D O Lucas L M Kelley S E Wilson 《Clinical and experimental immunology》1981,45(3):595-603
Intramuscular sensitization of hamsters with several forms of respiratory syncytial virus (RSv) caused proliferation of lung epithelium. In contrast, intranasal injection of live virus rarely resulted in this phenomenon. A correlation existed between proliferation of lung epithelium and presence of complement-fixing antibody, but not between lung disease and delayed skin reactions. Complement-fixing antibody to RSv was found to be independent of the influence of the thymus. 相似文献
76.
Anfossi N Lucas M Diefenbach A Bühring HJ Raulet D Tomasello E Vivier E 《European journal of immunology》2003,33(12):3514-3522
A common feature of hematopoietic activating immunoreceptors resides in their association at the cell surface with transmembrane signaling adaptors. Several adaptors, such as the CD3 molecules, FcRgamma and KARAP/DAP12, harbor intracytoplasmic immunoreceptor tyrosine-based activation motifs (ITAM) that activate Syk-family protein tyrosine kinases. In contrast, another transmembrane adaptor, DAP10, bears a YxxM motif that delivers signals by activation of lipid kinase pathways. We show here that the human signal-regulatory protein SIRPbeta1 can associate with both DAP10 and KARAP/DAP12 in a model of RBL-2H3 cell transfectants. In association with KARAP/DAP12, SIRPbeta1 complexes are capable of inducing serotonin release and tumor necrosis factor (TNF) secretion. By contrast,in the absence of KARAP/DAP12, engagement of SIRPbeta1:DAP10 complexes does not lead to detectable serotonin release or TNF secretion by RBL-2H3 transfectants. However, triggering of SIRPbeta1:DAP10 complexes co-stimulates RBL-2H3 effector function induced by sub-optimal stimulation of the endogenous FcepsilonRI complex. Therefore, we report here a cellular model in which the association of a cell surface receptor with various signaling adaptors dictates the co-stimulatory or the direct stimulatory properties of the complex. 相似文献
77.
A case of neonatal alloimmune thrombocytopenia due to fetomaternal incompatibility against the platelet specific antigen PlA2 (Zwb) is described. Anti-PlA2 antibodies were present in the maternal serum together with anti-HLA antibodies. Initial identification of the platelet-specific antibodies was achieved by using chloroquine-treated PlA1(+) and PlA1(-) platelets. Antibody specificity was later confirmed using a panel of platelets of known phenotype. 相似文献
78.
Kim YH; de Kretser DM; Temple-Smith PD; Hearn MT; McFarlane JR 《Molecular human reproduction》1997,3(4):307-313
Using mechanical and chemical dissection methods, fibrous sheath was
isolated both from normal ejaculated human spermatozoa and from rabbit
cauda epididymal spermatozoa. The same techniques did not produce a pure
preparation of fibrous sheath from ejaculated rabbit spermatozoa,
suggesting that further cross-linking and stabilization of sperm structures
occurs in response to components of the seminal plasma. The isolation
procedures were monitored by phase contrast microscopy and the purity of
the fibrous sheath was verified by electron microscopy. Sodium dodecyl
sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of isolated human
fibrous sheath revealed at least 14 protein bands of which the most
intensely stained were of molecular weight 84, 72, 66.2, 57, 32 and 28.5
kDa. The rabbit fibrous sheath revealed at least 10 protein bands, of which
the most intensely stained were 35.2, 32.7 and 28.5 kDa. The amino acid
composition of the purified fibrous sheath from human and rabbit
spermatozoa was similar, being high in aspartic acid and/or asparagine and
glutamic acid and/or glutamine, serine, alanine, leucine, lysine and
glycine, but low in histidine, tyrosine and isoleucine. This composition is
similar to that reported for the rat and suggests that mammalian sperm tail
fibrous sheaths are composed of similar types of proteins, although there
are apparent differences in protein components between species.
相似文献
79.
Elizabeth Olivares Fontt Alain Beschin Els Van Dijck Vincent Vercruysse Martin Bilej Ralph Lucas Patrick De Baetselier Bernard Vray 《Developmental and comparative immunology》2002,26(1):27-34
A cytolytic protein named Coelomic Cytolytic Factor-1 (CCF-1) was isolated from the coelomic fluid of the earthworm Eisenia foetida foetida. Despite the absence of any gene homology, CCF-1 showed functional analogy with the mammalian cytokine tumour necrosis factor (TNF), particularly based on similar lectin-like activity. Indeed, both CCF-1 and TNF recognise N,N'-diacetylchitobiose and exert lytic activity on African Trypanosoma brucei brucei. In this report, we show that South-American Trypanosoma cruzi trypomastigotes, but not epimastigotes, were lysed by earthworm coelomic fluid or purified CCF-1. However, T. cruzi was less susceptible to lysis than T. brucei brucei. This lytic effect of coelomic fluid and CCF-1 on T. cruzi trypomastigotes was partially inhibited in the presence of anti-CCF-1 monoclonal antibody, antibody neutralising the lectin-like activity of TNF or N,N'-diacetylchitobiose. In contrast, this lytic effect was completely inhibited when using T. b. brucei. In addition, T. cruzi components, upon recognition by CCF-1 in E. f. foetida coelomic fluid, triggered the prophenoloxidase cascade, an invertebrate defence mechanism. These results further extend the functional analogies of CCF-1 and TNF, suggesting that both molecules share a similar lectin-like activity that has been conserved as an innate recognition mechanism in invertebrates and vertebrates. They also establish a link between stercorarian (T. cruzi) and salivarian (T. brucei) trypanosomatids having divergent phylogenetic origins and patterns of evolution, but possessing closely related cell surface sugar moieties. 相似文献
80.
A self-setting single-component calcium phosphate cement 总被引:6,自引:0,他引:6
Following an original synthesis route, we have prepared a single-component calcium phosphate apatite-like powder which settles and hardens when mixed with deionized water in an approximative 1.2 g:1 ml ratio. This paper describes the first physico-chemical studies and characterizations of the material. Observations of its in vitro behavior show a slight volume contraction and toxicity against fibroblasts bone marrow cells on disks of compacted powder. It is suggested that after an improvement of the powder characters such as grain size, and the choice of another hardening liquid, to name a few, this material should be a potential--or an ingredient of--bone cement. 相似文献