Hemagglutination by Bacterial Suspensions with Special Reference to Shigella alkalescens.

Summary

1. Saline suspensions of S. alkalescens, B. bronchiseptica, H. pertussis, V. comma, S. pyogenes are capable of clumping human red blood cells.

2. Suspensions of S. alkalescens agglutinate human, monkey, and hog red blood cells, and do not agglutinate cells of certain other animal species.

3. The hemagglutinin of S. alkalescens can be separated from the bacterial cell by high speed centrifugation after successive freezing and thawing of bacterial suspensions.

4. The hemagglutinin of S. alkalescens is labile, being destroyed by heat, and spontaneously disappears from cultures on standing at 5° C for 6 weeks.