scholarly journals Interaction of rheumatoid factor and Entamoeba histolytica

1989 ◽  
Vol 31 (4) ◽  
pp. 207-212
Author(s):  
P.G. Kremsner ◽  
W. Graninger

The amoebae's cytotoxicity test and the amoebae's lysis test were used to show possible interactions between rheumatoid factor (RF) and Entamoeba histolytica. Amoebae's cytotoxic activity (ACA) was inhibited by affinity chromatography purified antiamoebae rabbit IgG (RIgG). Enhanced inhibition could be demonstrated with RIgG plus RF. But the same marked inhibition of ACA could be seen when replacing RF by heat inactivated normal human serum as a control. About 50% amoebae's lysis occurred when amoebae were brought together with native normal human serum (NNHS) as a source of complement. Amoebae's lysis increased to 60% when incubated with NHS plus human antiamoebae antibodies. No further augmentation could be obtained by the addition of RF. Using RIgG instead of human antibodies the lysis rate did not increase. Incubation of amoebae, NNHS, RIgG and RF even reduced amoebae's lysis. RF neither has an effect on ACA nor on complement mediated AL in vitro.

1969 ◽  
Vol 24 (11) ◽  
pp. 1442-1447 ◽  
Author(s):  
J. J. Picard ◽  
J. F. Heremans

The colloidal dye lithium carmine was added in vitro to normal human serum. Electrophoretic experiments showed that the dye was associated mainly with α2-globulins, small amounts with the albumin and only traces with the γ-globulins. The main complex was eluted with the macroglobulin peak obtained by gel filtration on Sephadex G-200 and sedimented in the heavy fraction on density gradient ultracentrifugation. The dye-protein complex could be precipitated with an antiserum specific for a2-macroglobulin. Gel filtration of a solution of pure a2-macroglobulin, to which lithium carmine was added, demonstrated that the dye was bound to this protein.


1981 ◽  
Vol 97 (2) ◽  
pp. 231-242 ◽  
Author(s):  
F. A. O. Mendelsohn ◽  
Christine D. Kachel

Abstract. Normal human serum markedly stimulated aldosterone production from rat adrenal glomerulosa cells incubated in Krebs Ringer bicarbonate medium (KRBGA). The effect was dose-related. In [K+] 3.6 mm KRBGA medium, serum stimulated aldosterone output to higher levels than those produced by maximal doses of serotonin (5 HT), angiotensin II (AII) or high [K+] (8.4 mm). Cells maximally stimulated by high [K+], 5 HT or AII in KRBGA medium were further stimulated by serum. The angiotensin analogue, [Sar1, Ala8]-AII abolished the effect of AII but not that of high [K+] or serum. Basal and ACTH-stimulated corticosterone outputs of rat fasciculata cells were not significantly affected by sera known to stimulate glomerulosa cells. Aldosterone stimulating activity of serum was dialysable and fully recovered in a serum ultrafiltrate. The serotonin blockers methysergide and metergoline abolished the aldosterone stimulating activity of serum but also depressed basal aldosterone output and methysergide reduced K+-stimulated output. Chymotrypsin digestion abolished the aldosterone stimulating activity of AII but not that of serotonin or serum. 5 HT concentration of sera was measured and found to be near the threshold for aldosterone stimulation. Sodium loading and depletion of 4 normal subjects did not consistently modify the aldosterone stimulating activity of their sera. In a supplemented medium (RPMI 1640), basal and K+-stimulated aldosterone outputs were higher than in KRBGA medium. Under these conditions serum stimulated aldosterone output in normal [K+] medium but only marginally in high [K+] medium. In RPMI medium, serum did not further stimulate cells maximally stimulated with serotonin. Serum appears to stimulate aldosterone production from glomerulsoa cells by two different mechanisms: One is probably due to a serotonin-like substance. A separate effect of serum, seen only in KRBGA medium, is to enhance aldosterone output of glomerulosa cells maximally stimulated by K+, 5 HT or AII.


2018 ◽  
Vol 184 ◽  
pp. 115-120
Author(s):  
Xuan Zhang ◽  
Xiao-Kun Hong ◽  
Su-Jin Li ◽  
De-Hua Lai ◽  
Geoff Hide ◽  
...  

Parasitology ◽  
1989 ◽  
Vol 98 (3) ◽  
pp. 401-407 ◽  
Author(s):  
G. Verducci ◽  
S. Perito ◽  
R. Rossi ◽  
E. Mannarino ◽  
F. Bistoni ◽  
...  

SUMMARYNormal human serum (HS) contains trypanolytic activity and agglutinins toTrypanosoma equiperdum, while such activities are not found in sera from a range of animals susceptible to infection. HS given toT. equiperdum-infected mice caused a rapid decrease in the number of circulating trypanosomes and protection from lethal infection. Trypanolytic activity of human serum was found to be associated, after DEAE chromatography and Sephadex G-200 gel filtration, with the fraction containing 19S antibodies. Immunofluorescence assays confirmed a binding of human IgM and C1qcomplement component onto the surface ofT. equiperdum. Anti-T. equiperdumactivity of HS was specifically directed toT. equiperdumsurface components and not to some mouse serum components adsorbed on parasites during the growth in the host, because HS adsorbedin vivoin CD-1 mice retained full protective and agglutinating properties. Trypanocidal activity appears in human serum about the 7th month after birth and persists until late in life. On the contrary, human purified high-density lipoprotein had no significantin vitroorin vivotrypanocidal activity. In conclusion, strong natural anti-T. equiperdumactivity in human serum was mainly mediated by natural antibodies of the IgM class. The presence of natural IgM active againstT. equiperdumin HS could represent one of the natural mechanisms of resistance of refractory hosts against trypanosome infections. This phenomenon provides further evidence that host specificity of trypanosomes may be partly conditioned by the presence of natural antibodies.


2002 ◽  
Vol 70 (1) ◽  
pp. 407-411 ◽  
Author(s):  
Chao-Ming Tsai ◽  
George Kao ◽  
Peixuan Zhu

ABSTRACT The sialylation of lipooligosaccharide (LOS) in Neisseria meningitidis plays a role in the resistance of the organism to killing by normal human serum. The length of the α chain extending out from the heptose I [Hep (I)] moiety of LOS influenced sialylation of N. meningitidis LOS in vitro and in vivo. The α chain required a terminal Gal and a trisaccharide or longer oligosaccharide to serve as an acceptor for sialylation. The disaccharide lactose (Galβ1-4Glc) in the α chain of immunotype L8 LOS could not function as an acceptor for the sialyltransferase, probably due to steric hindrance imposed by the neighboring Hep (II) with phosphorylethanolamine and another group attached.


Blood ◽  
1980 ◽  
Vol 55 (6) ◽  
pp. 955-959
Author(s):  
G de Klerk ◽  
RJ Vet ◽  
PC Rosengarten ◽  
R Goudsmit

The commercially available hemagglutination inhibition (HAI) assay kit for erythropoietin (ESF) was compared with the fetal mouse liver cell (FMLC) bioassay. No correlation was obtained ESF levels determined by both methods in a variety of pathologic sera. The HAI kit showed a great batch variability. Significant immunoreactivity was found in those fractions of a normal human serum and a human urinary ESF preparation that were not active in the FMLC bioassay. A very poor recovery of immunoreactivity was found when the international reference preparation for erythropoietin (second IRPE) was added to a normal human serum.


1973 ◽  
Vol 30 (02) ◽  
pp. 280-283 ◽  
Author(s):  
B Binder

SummaryBased on gelfiltration studies, the part of AT III which becomes bound to thrombin during the process of in vitro blood coagulation was calculated to be about 40% of total AT III. Complexes consisting of one AT III and one thrombin molecule could not be detected while fractions corresponding to molecular weights of about 190,000 Dalton show AT III as well as thrombin activities. The AT III - thrombin complex in normal human serum consists, therefore, of either 2 AT III and 2 thrombin molecules or of one AT III and 4 thrombin molecules.


1977 ◽  
Author(s):  
J. A. Conkie ◽  
J. F. Davidson

In an investigation of the early cleavage fragments resulting from fibrin(ogen)olysis, we have examined the nature of small peptides arising from the C-terminal part of the Aα chain of human fibrinogen.Antiserum to the carboxymethylated Aα chain of human fibrinogen has been prepared, and used to study the Aα-related antigens from (i) a plasmin digest of human fibrinogen, (ii) human serum, obtained from urokinase-treated normal plasma, and (iii) normal human serum. Using immunodiffusion and immunoelectrophoresis with anti-Aα antiserum, along with Polyacrylamide gel electrophoresis, at least two non-identical Aα -related antigens have been detected in a final plasmin digest of human fibrinogen. The largest of these antigens (MW 26,000) has been isolated and named Aα.-RA (26,000). This may be similar to the previously-described fragments, Hi2-Ala, fragment A or fragment H. Aα -related antigen has been produced by in vitro fibrinogenolysis in plasma and has been detected in the serum. In addition, small quantities of Aα -related antigen have been found in untreated normal human serum.These results suggest that anti-Aα antiserum is likely to be a useful reagent for the study of the early plasmin-derived fragments of fibrin(ogen)olysis in vitro and in vivo.


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