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M Stankiewicz

Publications and source records attributed to M Stankiewicz.

At least 109 records · Page 6Linked to original sources

Stimulation of the titre of a sheep serum factor that is related to the sheep complement system.

Serum from most sheep subjected to a single jugular bleeding, repeated bleeding or an intraperitoneal injection of yeast and repeated bleeding, showed an increase in the titre of a serum component called serum factor. Serum factor reached a peak titre 2 to 5 days after treatment started. For some sheep, the titre was elevated for a 9- to 12-day period whereas for others the titre dropped markedly on day 7 followed by a rise on day 9. Serum factor reacts with sheep erythrocytes sensitised with rabbit antibody (sheep E-rabbit A). Serum factor can be detected on sheep E-rabbit A using guinea-pig antiserum that reacts with sheep complement (C). Serum factor is inactivated by heating at 56 degrees C for 30 minutes, but is only partially inactivated at 50 degrees C for 30 minutes. The reaction of serum factor with sheep E-rabbit A is inhibited by chelators of Ca++ and/or Mg++. Serum factor appears to be related to the sheep C system. Preliminary results suggest it may he a component of the classical pathway of sheep C, possibly the second component, C2.

Journal Article↗

Haemolysis of human erythrocytes heavily sensitized with sheep amboceptor by sheep complement chelated with EGTA or Mg2+-EGTA.

Human erythrocytes sensitized with an agglutinating dose of either sheep anti-human erythrocyte antiserum, IgM, slow or fast gamma-globulin antibody are haemolysed by foetal lamb or sheep serum complement (C) in the presence of ethyleneglycoltetraacetic acid (EGTA) or Mg2+-EGTA but not ethylenediaminetetraacetic acid (EDTA) or triethylenetetraminehexaacetic acid (TTHA). Dialysis of the C source against phosphate buffered saline rendered it inactive, but addition of Mg2+ or Mg2+-EGTA restored haemolytic activity. Haemolysis of sensitized erythrocytes took place more rapidly in buffer containing Ca2+ and Mg2+ than in EGTA or Mg2+-EGTA. Heating the C source at 50 degrees C for 30 min or 56 degree C for 3 min abolished haemolytic activity. In the presence of EGTA or Mg2+-EGTA, haemolytic activity was restored to 50 degrees C-heated serum by a CM-cellulose fraction that contained sheep factor B. These results show that sheep C, in the presence of EGTA or Mg2+-EGTA will haemolyse human erythrocytes heavily sensitized with sheep amboceptor. The alternative pathway of sheep C is thought to be involved.

Animals↗

Alternative pathway activation of complement in fetal lamb serum by Trichostrongylus vitrinus larvae.

Fetal lamb serum (FLS) complement activated by incubation with Trichostrongylus vitrinus larvae was deposited on the larval surface and its presence was demonstrated by leucocyte and erythrocyte adherence reactions and by analysis of antisera from guinea-pig immunized with the larvae. The complement activation proceeded in the apparent absence of antibody and in the presence of ethylene glycol tetracetic acid (EGTA) or Mg++-EGTA but not ethylenediamine tetracetic acid (EDTA). FLS heated to 50 degrees C for 30 min was inactive, but activity was restored by addition of FLS factor B alone or factor B plus Mg++-EGTA. FLS treated with zymosan or inulin was inactive. These results suggest that this non-immune activation of sheep complement by T. vitrinus takes place via the alternative pathway.

Animals↗