Identification of inflammatory cells in bovine milk by flow cytometry
Version of Record online: 30 MAR 2005
Copyright © 1988 Wiley-Liss, Inc.
Volume 9, Issue 5, pages 463–468, September 1988
How to Cite
Redelman, D., Butler, S., Robison, J. and Garner, D. (1988), Identification of inflammatory cells in bovine milk by flow cytometry. Cytometry, 9: 463–468. doi: 10.1002/cyto.990090510
- Issue online: 16 JUN 2005
- Version of Record online: 30 MAR 2005
- Manuscript Accepted: 18 MAR 1988
- Manuscript Received: 7 JAN 1988
Cells recovered from normal or mastitic bovine milk were examined by flow cytometry. All milk samples contained particulate material that was heterogeneous in size and that produced a right-angle light-scatter signal equal to or greater than that produced by human or bovine neutrophils. Although this material labeled with Hoechst 33342, it produced fluorescence intensities below that of intact bovine cells, suggesting that it consisted of cell fragments. Mastitic milk additionally contained other populations of cells that were poorly resolved from the normal particulate material by size (electronic volume sensor) and right-angle light scatter. In order to improve this resolution, the milk cells were incubated with carboxydimethylfluorescein diacetate (CMFDA) to label intact cells. When milk samples labled with CMFDA were examined by dual-parameter analysis using green fluorescence and right-angle light scatter, five or more populations of cells could be identified in mastitic milk. These populations included intact and degenerate neutrophils, lymphocytes, including both small and activated cells, monocytes, and large activated macrophages containing many vacuoles and phagocytosed particles. Using this procedure, all the animals in the University of Nevada-Reno Holstein dairy herd were tested once a month for 6 months. In addition, individual animals with mastitis were examined one or more times each day during the course of the inflammatory process. In the routine screening, the flow cytometric examination detected mastitis before overt symptoms developed. In cows identified to have mastitis, the flow cytometric examination provided prognostic information regarding the success of treatments.