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Published on: April 6, 2017
THE PRODUCTION OF PURPURA BY DERIVATIVES OF PNEUMOCOCCUS : II. THE EFFECT OF PNEUMOCOCCUS EXTRACT ON THE BLOOD
1Hospital of The Rockefeller Institute for Medical Research.
Abstract:
A study has been made of the variation in number of the blood platelets, and the red and white blood cells of white mice injected with pneumococcus extract. The blood platelets were greatly diminished after the injection, the greatest decrease usually occurring after 24 hours. Purpuric lesions usually developed when the number of blood platelets became less than 500,000 per c.mm. Regeneration of the platelets was accomplished by the 4th to the 9th day but there was an overregeneration and the return to normal did not take place until 2 weeks had elapsed. The red cells were also greatly reduced in number, but the rate of their destruction and regeneration was somewhat slower than that of the platelets. The leucocytes were slightly if at all influenced by the pneumococcus extract. Pneumococcus extracts were shown to be thrombolytic and hemolytic. Heat destroyed the activity of both the lysins in vitro. Heated extract produced purpura in mice but did not cause a severe anemia. Extracts adsorbed with either blood platelets or red blood cells showed a marked diminution in their thrombolytic and hemolytic activity in vitro. Such extracts, however, produced purpura as well as severe anemia and thrombopenia in mice.
Insights
Pneumococcus extract significantly reduces blood platelets and red blood cells in mice, causing purpura. While heated extracts lose some activity, they still induce purpura, highlighting the extract's potent effects on blood components.
Area of Science:
- Hematology
- Immunology
- Microbiology
Background:
- Pneumococcus infections can lead to various complications.
- The effects of pneumococcus extracts on blood cell counts and coagulation are not fully understood.
Purpose of the Study:
- To investigate the impact of pneumococcus extract on blood platelets, red blood cells, and white blood cells in mice.
- To determine the thrombolytic and hemolytic properties of pneumococcus extracts.
- To assess the role of heat and adsorption in modulating the extract's activity.
Main Methods:
- White mice were injected with pneumococcus extract.
- Blood cell counts (platelets, red cells, white cells) were monitored over time.
- Thrombolytic and hemolytic activity was assessed in vitro.
- Extracts were subjected to heat treatment and adsorption with blood cells.
Main Results:
- Pneumococcus extract caused a significant decrease in blood platelets and red blood cells, with purpuric lesions appearing at low platelet counts.
- Platelet regeneration occurred by day 4-9, with over-regeneration and a 2-week return to normal.
- The extract exhibited thrombolytic and hemolytic activity in vitro, which was reduced by heat.
- Heated extract induced purpura but not severe anemia, while adsorbed extracts showed diminished lysin activity but still caused purpura, anemia, and thrombopenia.
Conclusions:
- Pneumococcus extract has potent thrombolytic and hemolytic effects, leading to significant hematological changes and purpura in mice.
- Heat treatment partially neutralizes the extract's activity, but residual components can still cause adverse effects.
- Adsorption studies suggest specific interactions between extract components and blood cells, influencing both in vitro activity and in vivo pathogenicity.
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