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Updated: Oct 24, 2026

Human Peripheral Blood Neutrophil Isolation for Interrogating the Parkinson's Associated LRRK2 Kinase Pathway by Assessing Rab10 Phosphorylation
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Individual variation of nucleoside triphosphate pyrophosphohydrolase activity in human erythrocytes, granulocytes,

V L Verhoef, S A Fuller, A J Morris

    Biochemical Genetics
    |April 1, 1980
    PubMed

    Analysis of the nucleoside triphosphate pyrophosphohydrolase specific activity of red cells obtained from a random Caucasian population indicated at least two subclasses. The specific activity of 18% of the population ranged from undetectable activity to 27.5 nmol ITP cleaved/20 min/mg hemoglobin. The remainder of the population had higher activity, 27.5-125 nmoles ITP cleaved/20 min/mg hemoglobin. The variation of NTPH activity evident in the red cells of an individual is reflected in granulocytes, lymphocytes, and platelets of that individual. Erythrocyte activity ranges from 0.7 to 21 units (nmol of ITP cleaved in 20 min)/10(7) cells, granulocytes have 17-201 units/10(7) cells, lymphocytes have 91-462 units/10(7) cells, and platelets have 1.1-7.1 units/10(7) platelets. These cell differences are discussed with respect to the hypothesis that NTPH prevents incorporation of ITP or dITP into nucleic acids.

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