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PubMed · 965728

Enhanced E- and EAC-rosette formation by neuraminidase.

T Han·J Minowada
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Abstract

Pre-treatment by neuraminidase of lymphocytes obtained from peripheral blood of normal donors significantly enhanced E- and EAC-rosette formation. Of other lymphoid cells only spleen cells showed significant enhancement of E-rosettes. The EAC-rosettes slightly increased when the peripheral blood lymphocytes from patients with acute lymphoblastic leukemia or chronic lymphocytic leukemia and MOLT-4 lymphoid cells were pre-treated with this enzyme. The EAC-rosettes were not increased by neuraminidase treatment of phytohemagglutinin-induced blasts, thymus cells or spleen cells. Pre-treatment of peripheral blood lymphocytes with neuraminidase also increased the proportion of stable E-rosettes resistant to incubation at 37 degrees C and to vigorous shaking. Various concentrations of neuraminidase (1-100 U/ml) produced enhancement of E- and EAC-rosettes with the highest activity at 25 and 50 U/ml. Neuraminidase treatment of sheep red blood cells failed to increase the proportion of E-rosettes of peripheral blood lymphocytes. The increased rosette forming capacity induced by neuraminidase is probably related to changes in lymphocyte surface properties.

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Complement System ProteinsErythrocytesHumansImmune Adherence ReactionLymphocytesNeuraminidaseSpleenThymus GlandJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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T Han, J Minowada. 1976. Enhanced E- and EAC-rosette formation by neuraminidase.. https://doi.org/10.1016/0022-1759(76)90046-6

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