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M Stankiewicz

Publications and source records attributed to M Stankiewicz.

At least 91 records · Page 5Linked to original sources
PubMed1988

Effects of Trichinella spiralis infections upon bone marrow stem cells in BALB/c mice.

Trichinella spiralis infections provoke a variety of responses in the host, some of which involve stem cell proliferation and myeloid cell maturation, increases in the mast cell precursor cell populations, and maturation and eosinopoiesis. Very little is known about the influence of T. spiralis upon bone marrow stem cells and splenic colony formation. In the present communication we report that T. spiralis infection in mice stimulates the generation of colony-forming units in the spleen (CFU-S). Passive transfer of bone marrow cells from uninfected BALB/c mice to X-irradiated (650 R) T. spiralis-infected recipients resulted in a significant increase of CFU-S at 14 and 24 days postinfection. Passive transfer of bone marrow cells from T. spiralis-infected mice to X-irradiated uninfected mice also resulted in increased numbers of CFU-S in the donor mice at 24 days postinfection. These findings strongly suggest that T. spiralis infection conditions the microenvironment in the spleen which stimulates CFU-S.

Animals↗
PubMed1986

Sheep serum complement sensitisation of sheep erythrocyte-rabbit antibody complexes for haemolysis by guinea-pig complement plus EDTA or Mg2+-EGTA.

Sheep erythrocyte (E)-rabbit antibody (A) complexes incubated with sheep serum diluted up to 1:5120 or 1:20480 and washed can be haemolysed by guinea-pig (g-p) serum (complement, C) containing EDTA or Mg2+-EGTA respectively as haemolytic finishing reagents. Sheep E carrying a high dose of rabbit A were necessary for this reaction, particularly with g-p C-EDTA. G-p serum (stored by freezing) was active as a haemolytic finishing reagent with both EDTA and Mg2+-EGTA. Reconstituted freeze-dried g-p serum (also stored by freezing) was haemolytically active with Mg2+-EGTA only. G-p serum preserved by Richardson's method did not function as a finishing reagent with EDTA or Mg2+-EGTA. A non-haemolytic prozone occurred with sheep E-rabbit A treated with dilutions of sheep serum or body fluid up to 1:160, particularly when g-p C (frozen)-EDTA was used as the finishing reagent. Sheep E-rabbit A were sensitized by serum, foetal lamb serum, pericardiac-, synovial- or ovarian follicle-fluids colostrum or milk for haemolysis by g-p C (frozen)-EDTA or -Mg2+-EGTA. With the C3 inhibitors cobra venom factor or salicylaldoxime, serum sensitisation of sheep E-rabbit A for haemolysis by g-p C (frozen)-EDTA or -Mg2+-EGTA was not blocked. Sensitisation by serum heated at 50 degrees C for 30 min (partial inactivation of C2) was incomplete. Inhibitors of C1 (antrypol, chelators of Ca2+ or heating serum at 56 degrees C for 30 min) partially or fully blocked sensitisation for haemolysis by both g-p C (frozen)-EDTA or -Mg2+-EGTA. These results show that at a minimum, components C1, C4 and C2 are present and functionally active in serum and some body fluids of sheep.

Animals↗
PubMed1986

Agglutination of sheep erythrocyte-rabbit antibody complexes treated with sheep serum by a rabbit antiserum specific for the third component (C3) of sheep complement.

Sheep E-rabbit A incubated with sheep serum for up to 20 min at 39 degrees C and washed were agglutinated by a rabbit antiserum (anti-inulin-foetal lamb serum) that was specific for sheep C3. If incubated for longer than 20 min at 39 degrees C, there was less sensitisation. Such a complex was not readily generated at 17 degrees C whereas there was no reaction if incubated at 2 degrees C. Once the sheep E-rabbit A-sheep C complex had been generated at 39 degrees C and washed free of sheep serum, it could still be agglutinated after overnight storage at 4 degrees C. Addition of chelators of Ca2+ and/or Mg2+ or antrypol or cobra venom factor (a specific inhibitor of C3) prevented sensitisation of sheep E-rabbit A by sheep serum for agglutination. These results show that sheep serum C3 was taken up by sheep E-rabbit A and its presence on this indicator demonstrated by agglutination using a rabbit antiserum specific for sheep C3.

Animals↗
PubMed1985

Variations in sheep serum conglutinating complement activity and pathway involved in reactivity with sheep erythrocytes sensitized by rabbit antibody.

Based on conglutination tests with the sheep E-rabbit A indicator system, three types of sheep sera were encountered. Type 1 sera failed to directly conglutinate or sensitize sheep E-rabbit A for conglutination by bovine conglutinin. Type 2 sera also failed to directly conglutinate sheep E-rabbit A but sensitized the indicator for conglutination by bovine conglutinin. Type 3 sera both directly conglutinated and sensitized sheep E-rabbit A for conglutination. Changes in serum type were induced in sheep by venepuncture (type 1 to type 2) or venepuncture and an intraperitoneal injection of yeast cells (type 2 to type 3). Direct conglutinating activity of type 3 sera was inhibited by heating serum at 50 degrees C for 30 min and was not restored by alternative activation pathway factor B. Chelation of Ca2+ in type 2 and 3 sera blocked sensitization of sheep E-rabbit A for conglutination by bovine conglutinin, indicating that the classical activation pathway was involved.

Acetylglucosamine↗
PubMed1985

Electrophoretic and serological analysis of mouse and rabbit antisera to zymosan or inulin treated with foetal lamb serum.

Most mouse antisera raised to zymosan treated with FLS containing Ca2+ and Mg2+ precipitated C3 and two other proteins from electrophoresed sheep serum. Rabbit antisera to zymosan-FLS precipitated C3 and three sheep serum proteins. All these antisera agglutinated sheep E-rabbit A complexes sensitized with sheep C at room temperature. Mouse antisera to zymosan treated with FLS containing Mg2+-EGTA and mouse antisera to inulin treated with FLS containing Ca2+ and Mg2+ or Mg2+-EGTA, precipitated only C3 from electrophoresed sheep serum, but did not agglutinate sheep E-rabbit A-sheep C. These results, together with antiglobulin studies indicate that zymosan, probably through a reaction with natural antibody in the FLS can activate sheep C by a mechanism that involves a Ca2+ and Mg2+-dependent pathway. In the presence of Mg2+-EGTA, zymosan and inulin activate sheep C via a Mg2+-dependent pathway. The results also show that antisera that will precipitate sheep C3 from electrophoresed sheep serum can be raised by immunizing mice and rabbits with inulin that has been treated with FLS or zymosan treated with FLS containing Mg2+-EGTA.

Animals↗
PubMed1984

Variations in sheep serum conglutinating and haemolytic activity for sheep erythrocytes sensitized by rabbit antibody.

Based on conglutinating and haemolytic reactions with sheep erythrocytes (E) sensitized by rabbit antibody (A), three types of sheep sera were encountered. Type 1 sera do not conglutinate or haemolyse sheep E-rabbit A. Type 2 sera failed to conglutinate or haemolytically active. Type 3 sera have both activities. Serum from one type 1 sheep still failed to conglutinate 5 days after venepuncture but was not haemolytically active (i.e., type 2). Some sheep that initially had type 2 sera had, five days after an intraperitoneal injection of yeast cells, sera with conglutinating activity (type 3 sera). Type 1, 2 and 3 sera all had haemolytic activity with human E-sheep A indicator cells. Pooled type 3 sera have the highest conglutinating titres with sheep E-rabbit A after 10 min incubation at 39 degrees C. At this stage, the haemolytic titres were very low. From 10 min, the conglutinating titres decreased whereas the haemolytic titres gradually increased until 80 min. Optimal conglutinating activity required less rabbit A to sensitize sheep E than did haemolytic activity.

Animals↗
PubMed1983

Inhibitory activity of heated ewe serum for ewe and ram serum complement.

In the presence of an indicator antigen-antibody complex, the complement (C) activity in ewe and ram serum was reduced or abolished by addition of ewe serum that had been heated at 56 degrees C for 10 minutes. Pre-incubation of heated ewe serum at 39 degrees C for 30 minutes with the C source prior to addition of the indicator system or addition at the same time caused similar reductions in C activity. Results from the haemolytic, conglutinating and haemagglutinating activities studied indicate that the ewe serum inhibitor(s) reacts with activated classical or alternative activating pathway components and/or the third component of C (C3). The presence of a potent C inhibitor(s) in ewe serum probably accounts for the low sheep C titres with some assay systems. As the heated ewe serum did not appear to activate ewe or ram C per se, it is more appropriate to regard it as 'inhibitory' rather than 'anticomplementary'.

Journal Article↗
PubMed1983

Effect of oxafun on the antibiosis between Bacillus subtilis and Phoma betae.

The fungicide oxafun decreased the production of antibiotic substances active against Phoma betae, by Bacillus subtillis. This was confirmed by reduced effectiveness of antibiotic substances against Phoma infection in micropot experiment. Besides, the bacterial metabolites effected cell membrane permeability of mycelium and resulted in some relationships of fungicide and antibiotic substances.

Anilides↗
PubMed1982

Conglutination and haemolysis of unsensitized human erythrocytes by bovine serum complement.

Unsensitized human erythrocytes (E) were haemolyzed by bovine serum to a titre of 1:16-1:32. In the single dilution beyond the haemolytic endpoint, the cells were conglutinated. In dilutions in which haemolysis occurred, cells were conglutinated before being lyzed. With no or minimal haemolysis, conglutination to 1:32-1:64 occurred in tests using insulin-absorbed serum, serum heated at 50 degrees C for 30 min and in tests incubated at 4 degrees C for 30 min. In two-stage tests, EDTA and Mg2+-EGTA prevented bovine C sensitization of human E for conglutination by bovine serum heated at 56 degrees C for 30 min. EDTA prevented haemolysis, but haemolysis to 1:16-1:32 occurred with serum dilutions containing Mg2+-EGTA. Haemolytic activity was restored to serum heated at 50 degrees C by a factor B-containing fraction. Conglutination and haemolysis were blocked by heating serum at 56 degrees C for 30 min and were reduced to low titres by absorbing serum with zymosan. These results strongly suggest that the conglutination reaction involved the classical activation pathway whereas the haemolytic reaction involved the alternative activation pathway. Thus, with dilutions of untreated or treated bovine serum, two C-dependent reactions and the pathways involved can be demonstrated by using unsensitized human E as an indicator system.

Agglutination↗