Survival of 59Fe-labeled erythrocytes in cross-transfused equine blood.

The research focused on examining how well transfused, iron-labeled red blood cells survive in horses. The study found that the survival rate of these cells, after being transferred into oth+er horses, varied significantly – some retaining a high percentage of the iron-labeled cells for days while others showing a rapid drop off.

Research Methodology

• The researchers transfused iron (59Fe)-labeled red blood cells, which were mixed with unlabeled serum, from one donor horse into six other horses.
• This process of transfusion was carried out twice and in both instances, the survivability of the transfused cells was monitored through time by measuring the level of radioactivity in the red blood cells.

Results and Observations

• In the first transfusion, the concentration of labelled red blood cells ranged between 60% to 100% of the transferred dose for four days. Following this, the radioactivity levels plunged to less than 10% in three horses by the sixth day.
• In the three remaining horses, the radioactivity rapidly decayed, hitting minimal levels within 48 hours.
• During the second transfusion, different horses demonstrated varying responses. For one horse, 80% of the dose remained in the circulating red blood cells for four days. However, two horses showed a rapid decline in the radiolabeled red blood cells, hitting minimal levels within 48 hours. Interestingly, two other horses showcased minimal radioactivity even immediately after the transfusion.
• One horse experienced an anaphylactic shock and died during the second transfusion.
• Throughout the study, traditional tests for erythrocyte compatibility such as direct agglutination, antiglobulin, and the hemolytic tests were not effective in predicting the survival of the transfused red blood cells.

Conclusion

• The study concluded that the survival of transfused 59Fe-labeled red blood cells in horses varied significantly. Therefore, traditional methods of predicting the survival of these cells were deemed ineffective.