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Anti-CD9 monoclonal antibodies induce homotypic adhesion of pre-B cell lines by a novel mechanism

, : Anti-CD9 monoclonal antibodies induce homotypic adhesion of pre-B cell lines by a novel mechanism. Journal of Immunology 144(5): 1607-1613

Anti-CD9 mAb are known agonists of platelet aggregation, but have not been implicated in cell-cell adhesion. We show here in an experimental system that the anti-CD9 mAb 50H.19, ALB6, and BA-2 can induce rapid, and irreversible, homotypic aggregation of the CD9-positive pre-B lymphoblastoid cell lines NALM-6 and HOON, but not of the CD9-negative B cell line Raji. The specificity of the response is indicated by the failure to effect aggregation with mAb directed to CD24, or to HLA class I Ag. The initiation of strong homotypic aggregates of lymphoid cells is a property ascribed to lymphocyte function-associated Ag-1 (LFA-1), a member of the beta 2 subfamily of leukocyte integrins. We show that CD9-induced aggregation is an active process which proceeds at 37 degrees C, but not at 4 degrees C, requires the expenditure of metabolic energy, and a functioning cytoskeleton, and is not inhibited by Arg-Gly-Asp-Ser peptide. These are properties described for LFA-1-mediated aggregation. However, because beta 2-integrins are not expressed on NALM-6 or HOON cells, they are not the mediators of CD9-induced aggregation. In contrast to LFA-1-mediated adhesion which is Mg2+ dependent, CD9-induced adhesion has an absolute requirement for Ca2+, but not Mg2+, indicating that a Ca2(+)-dependent event is sufficient for adhesion. However, Mg2+ enhances adhesion even at optimal concentrations of Ca2+, implicating an additional Mg2(+)-dependent event which requires Ca2+ to be effective. These findings suggest that CD9 Ag regulates a novel mechanism for promoting tight cell-cell adhesion which requires both Ca2+ and Mg2+ for optimal expression.


PMID: 2307836

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Mulholland, G.W., 2005: Re-Analysis of the Uncertainty of the 0.895 µm Diameter (NIST SRM(®) 1690) and the 0.269 µm Diameter (NIST SRM(®) 1691) Sphere Standards. The uncertainties of the mean diameters of the nominal 1.0 µm SRM(®) 1690 polystyrene spheres and of the nominal 0.3 µm SRM(®) 1691 polystyrene spheres are recomputed using the current NIST Guidelines for computing uncertainty. The revised exp...

Higgins, M.S.; Marco, A.P., 1992: An aid in oral fiberoptic intubation. Anesthesiology 77(6): 1236-1237

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Takeuchi, H., 1993: Prevention of recurrence of urolithiasis. Japanese Journal of Clinical Urology 47(4): 213-215

Rossi, G.B.nedini, M.T.akiris, G.G.akoumakis, S., 1992: On regional drought estimation and analysis. The main objective of this paper is to review the existing methodologies for the estimation and analysis of regional drought. As a first step, point drought methods are presented. Further emphasis is given to the definition and estimation of regio...

Bonder, B., 1985: Standardized assessments: ethical principles for use. American Journal of Occupational Therapy 39(7): 473-474

Rowell C.H.F., 1970: Incremental and decremental processes in the insect central nervous system. Horn, Gabriel And Robert A Hinde (Edited By) Short-Term Changes in Neural Activity And Behavior Symposium Vii + 628p Illus Cambridge University Press: New York, N Y , U S A 237-280

Silverman, F., 1979: Asthma and respiratory irritants (ozone). Asthmatics appear to be more susceptible to the effects of air pollutants than nonasthmatics. The present studies were undertaken to examine the effects of exposing asthmatics to ozone concentrations that occur in the environment. Seventeen well-d...

Gomatam J.; Macdonald N., 1975: Time delays and stability of 2 competing species. Mathematical Biosciences 24(3-4): 247-256

Tharrington, G.J. ; Ashton, D.H.; Hatfield, J.R.; Fry, F.H., 1978: Nonspecific staining of a lactobacillus plantarum by salmonella fluorescent antibodies. Salmonella fluorescent antibody (FA) positives but cultural negatives were encountered in pasta samples. Salmonella FA positives were caused by an organism identified as a L. plantarum designated strain GT. Brilliant green incorporated into lactos...