PMID- 7664628
OWN - NLM
STAT- MEDLINE
DCOM- 19951006
LR  - 20191210
IS  - 0196-4763 (Print)
IS  - 0196-4763 (Linking)
VI  - 20
IP  - 2
DP  - 1995 Jun 1
TI  - Measurement of tumor necrosis factor activity by flow cytometry.
PG  - 181-4
AB  - Tumor necrosis factor-alpha (TNF-alpha) is a monokine of 17 kDa produced by 
      activated macrophages and various cells involved in the immune system. We propose 
      a new method for the measurement of TNF activity using flow cytometry. After an 
      incubation with TNF, L929 cells were harvested and treated with a calcein-AM and 
      ethidium homodimer-1 solution. Nonfluorescent calcein-AM is hydrolyzed by 
      intracellular esterases to yield fluorescent calcein. The ethidium homodimer-1 is 
      a high-affinity red fluorescent DNA dye that is internalized only through altered 
      cell membranes. A very good correlation was observed between the calcein 
      fluorescence intensity and the number of viable cells as well as the ethidium 
      fluorescence and the number of cells with altered membranes. The assay is 
      sensitive, inexpensive, and correlates with the already reported crystal violet 
      assay while measuring membrane alteration by TNF. It allows the simultaneous 
      measurement of total living and dead cells. There is no interference with culture 
      medium components. This method is rapid and may be used for routine measurement 
      of TNF activity.
FAU - Levesque, A
AU  - Levesque A
AD  - Department of Biochemistry, Faculty of Medicine, Universite Laval Sainte-Foy, 
      Quebec, Canada.
FAU - Paquet, A
AU  - Paquet A
FAU - Page, M
AU  - Page M
LA  - eng
PT  - Journal Article
PL  - United States
TA  - Cytometry
JT  - Cytometry
JID - 8102328
RN  - 0 (Fluoresceins)
RN  - 0 (Fluorescent Dyes)
RN  - 0 (Recombinant Proteins)
RN  - 0 (Tumor Necrosis Factor-alpha)
RN  - 148504-34-1 (calcein AM)
RN  - 61926-22-5 (ethidium homodimer)
RN  - EN464416SI (Ethidium)
SB  - IM
MH  - Animals
MH  - Cell Death/drug effects
MH  - Ethidium/analogs & derivatives
MH  - Evaluation Studies as Topic
MH  - Flow Cytometry/*methods/statistics & numerical data
MH  - Fluoresceins
MH  - Fluorescent Dyes
MH  - Humans
MH  - L Cells
MH  - Mice
MH  - Recombinant Proteins/analysis/toxicity
MH  - Sensitivity and Specificity
MH  - Tumor Necrosis Factor-alpha/*analysis/toxicity
EDAT- 1995/06/01 00:00
MHDA- 1995/06/01 00:01
CRDT- 1995/06/01 00:00
PHST- 1995/06/01 00:00 [pubmed]
PHST- 1995/06/01 00:01 [medline]
PHST- 1995/06/01 00:00 [entrez]
AID - 10.1002/cyto.990200211 [doi]
PST - ppublish
SO  - Cytometry. 1995 Jun 1;20(2):181-4. doi: 10.1002/cyto.990200211.