摘要:

SUMMARYIn this review the old concept of severe malaria as a toxic disease is re‐examined in the light of recent discoveries in the field of cytokines. Animal studies suggest that the induction of TNF by parasite‐derived molecules may be partly responsible for cerebral malaria and anaemia, while hypoglycaemia may be due to direct effects of similar molecules on glucose metabolism. These molecules appear to be phospholipids and we suggest that when fully characterized they might form the basis of antitoxic therapy for malar

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb01019.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

SUMMARYTreatment with an anti‐IL‐4 monoclonal antibody protected susceptible C57BL/6 mice against challenge with an avirulent strain of T. gondii. Antibody therapy with 100 [ig on days 0 and 7 post infection resulted in 100% survival of C57/BL6 mice infected orally. Survival was dose‐dependent. Treatment prolonged parasitaemia but did not alter tissue parasite load. Increased serum IgG2a and IFN‐γ levels, together with low levels of IgG1, in mice treated with anti‐IL‐4 or an isotype control, indicated a trend towards a predominant Thl response in all survivors. The persistence of an IgE response after treatment suggests that endogenous IL‐4 was only partly neutralized or that other factors can induce the production of IgE in murine

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb01020.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

SUMMARYA number of T cell hybridomas were produced to adult worm homogenate (AWH) antigen of the nematode parasite Heligmosomoides polygyrus. All of the hybridomas were of the H‐2dhaplotype and could potentially accept antigen in the context of either the Ador Ed, H‐2 molecules. Three types of antigen presentation were observed, with some of the T cell hybridomas accepting antigen in the context of the E and some in the context of the A molecule. A third type of hybridoma responded to antigen presented by paraformaldehyde fixed APC, but only when APCs were Epositive. These same hybridomas, were however, stimulated by A WH, when the antigen was presented by syngeneic but unfixed, E positive or E negative A PC. Therefore these data indicate that certain H. polygyrus‐specfic T cell hybridomas can accept parasite antigen when presented in the context of either the H‐2 A or E molecule, but the presentation of antigen by the two different MHC Class II molecules, can apparently utilize differing processing mech

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb01021.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

SUMMARYIn the present study we have investigated the fluid phase activation of the complement (C) alternative pathway by Echinococcus granulosus sheep hydatid cyst fluid (SHCF) and its higher molecular weight fraction (SHCF‐I) by quantitating the formation of both the terminal C intermediary C5b6 complex and the terminal C complex (TCC). Our results show that in vitro C activation progresses beyond the C5 step suggesting that potentially lytic complexes may be generated in vivo. In addition, SHCF and SHCF‐I glucidic moieties are probably involved in C activation since 80% and 86% of SHCF and SHCF‐I activity respectively was destroyed by period‐ate oxidation. Furthermore, partial deglycosylation with Peptide N‐Glycosidase F of SHCF‐I which had been digested with Pronase E, released an active fraction (MW<14KDa) which bound to Soybean agglutinin, suggesting that N‐linked oligosaccharides containing α‐or β‐linked N‐acetyl galactosamine play a role in

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb01022.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

SUMMARYThe presence of sera factors able to inhibit both neutrophil chemotaxis and phagocytosis was observed in all patients studied at two months from infection caused by Trichinella britovi and in most of them after one year. Human neutrophils with eosinophils are able to kill T. spiralis newborn larvae in an ADCC system and their major cytotoxic mechanism is oxidative metabolism products. We evaluated the effect of trichinellosis sera on neutrophil oxidative burst to determine if neutrophils are affected by circulating factors during infection. Cells were incubated with sera from trichinellosis patients. Basal or stimulated Superoxide Anion (SA) production and chemilumines‐cence in response to different stimulation (PMA, f‐MLP, opsonized yeasts) of neutrophils incubated with trichinellosis sera were evaluated and compared with those of cells incubated with control sera. The results show that basal SA production was inhibited by 66% of sera and stimulated by 11%. On the contrary f‐MLP stimulated production was significantly increased by 22% sera, and inhibited by none. Chemiluminescence in response to f‐MLP or PMA was inhibited by 46 and 80% of sera, respectively. These results show that trichinellosis sera can modulate not only SA production but also other steps of the oxidative burst, irrespective of the stimulating agent, so suggesting that different neutrophil activation pathways are affected. Increased IL‐2 levels observed in most of the sera did not correlate with the inhibiting capacity of sera. The hypothesis of a parasite origin of the inhibiting factors is discussed in the light of host‐parasite re

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb01023.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

SUMMARYThe efficacy of praziquantel treatment was significantly enhanced (P<0.01) in CBA/Ca mice that had been immunized prior to Schistosoma mansoni infection with a crude extract of worm membrane antigens. In Western immunoblots sera from the worm antigen‐immunized animals had a poly specific antibody response, with a 25–27 kDa antigen being reacted against with particular intensity. A molecule of similar size was also recognized by rabbit antisera raised against an antigen with esterase activity that has been previously identified as a sensitive target for drug‐antibody synergy. The increase in efficacy of subcurative doses of praziquantel in immunized animals is attributed to drug‐induced tegumental damage causing antigens to become exposed on the worm surface. Thus, specific antigens, including the 25–27kDa antigen, become accessible to circulating schistosomicidal antibodies. The role of antibodies that can synergize with praziquantel to kill schistosome worms is d

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb01024.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

SUMMARYThe antibody response to two different epitopes located in the C‐terminal 19 kDa fragment of the Plasmodium falciparum merozoite surface protein‐1 (MSP‐119) has been studied using a competitive ELISA based on the inhibition of monoclonal antibody (MoAb) binding by serum samples. Sera from children aged three to eight years who suffered clinical symptoms of malaria, or were partially immune with an asymptomatic infection, and from adults all living in The Gambia, West Africa were tested. The results suggest that the antibody response to MSP‐1 iQ has a role in naturally‐acquired immunity in Gambian ind

ISSN:0141-9838    

DOI:10.1111/j.1365-3024.1995.tb01025.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY