PMID- 1717078
OWN - NLM
STAT- MEDLINE
DCOM- 19911114
LR  - 20210216
IS  - 0006-4971 (Print)
IS  - 0006-4971 (Linking)
VI  - 78
IP  - 8
DP  - 1991 Oct 15
TI  - Role of glycoprotein IIa (beta 1 subunit of very late activation antigens) in 
      platelet functions.
PG  - 2021-6
AB  - Very late activation antigens (VLAs) are glycoproteins (GPs) that play a major 
      role in platelet adhesion to extracellular matrix. These GPs, members of the 
      integrin family, are heterodimer complexes with different alpha subunits 
      noncovalently associated with a common beta 1 subunit known as GPIIa. GPIa-IIa 
      (also known as VLA2), GPIc-IIa (VLA5), and GPIc*-IIa (VLA6) are involved, 
      respectively, in platelet adhesion to collagen, fibronectin, and laminin. At this 
      stage, very little is known about the role of GPIIa in platelet adhesive 
      functions. In this study, we have generated a monoclonal antibody (MoAb) (LYP22) 
      directed against GPIIa. Immunoaffinity chromatography using LYP22 combined with 
      two-dimensional nonreduced-reduced sodium dodecyl sulfate-polyacrylamide gel 
      electrophoresis shows that the antibody brings down all VLA subunits. Western 
      blots indicate that the binding site of LYP22 on GPIIa is disulfide 
      bridge-dependent. The number of LYP22 binding sites is not increased on 
      stimulation with thrombin and is in the range of what is observed with another 
      anti-GPIIa MoAb (A-1A5). LYP22 is the first anti-GPIIa MoAb to inhibit 
      aggregation and secretion of washed platelets stimulated with collagen, thrombin, 
      or arachidonic acid. Moreover, the lag-phase usually observed on collagen 
      stimulation is significantly prolonged (by 60 seconds) in the presence of LYP22. 
      This lag-phase, mediated by LYP22, is also observed in the presence of plasma 
      proteins and is coupled with a reduced effect on collagen-induced platelet 
      aggregation. In addition, LYP22 affects the adhesion of resting platelets to type 
      III collagen, but not to fibronectin, laminin, or type I collagen. These results 
      strongly indicate that the site on GPIIa, bearing the LYP22 epitope, is an active 
      participant in signal transduction controlling platelet functions.
FAU - Parmentier, S
AU  - Parmentier S
AD  - INSERM U.331, Faculte de Medecine Alexis Carrel, Lyon, France.
FAU - Catimel, B
AU  - Catimel B
FAU - McGregor, L
AU  - McGregor L
FAU - Leung, L L
AU  - Leung LL
FAU - McGregor, J L
AU  - McGregor JL
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Blood
JT  - Blood
JID - 7603509
RN  - 0 (Antibodies, Monoclonal)
RN  - 0 (Epitopes)
RN  - 0 (Macromolecular Substances)
RN  - 0 (Platelet Membrane Glycoproteins)
SB  - IM
MH  - Antibodies, Monoclonal
MH  - Blood Platelets/*physiology
MH  - Epitopes
MH  - Humans
MH  - Macromolecular Substances
MH  - Platelet Aggregation/physiology
MH  - Platelet Membrane Glycoproteins/*physiology
MH  - Signal Transduction/immunology
EDAT- 1991/10/15 00:00
MHDA- 1991/10/15 00:01
CRDT- 1991/10/15 00:00
PHST- 1991/10/15 00:00 [pubmed]
PHST- 1991/10/15 00:01 [medline]
PHST- 1991/10/15 00:00 [entrez]
AID - S0006-4971(20)82248-4 [pii]
PST - ppublish
SO  - Blood. 1991 Oct 15;78(8):2021-6.