A neutrophil migration-inducing lectin from Artocarpus integrifolia.
A neutrophil migration-inducing protein has been isolated from the saline extract of Artocarpus integrifolia seeds by successive sugar affinity chromatography steps during which the protein was not absorbed by D-galactose resin, and then was absorbed to and eluted from D-mannose resin by 0.1 M D-mannose. Gel filtration on Superdex 75 HR indicated a molecular mass of 52 kDa when 0.1 M D-mannose was present in the elution buffer. A single band of apparent molecular mass of 13 kDa was demonstrable by SDS-PAGE only after heating, both in the presence and absence of reducing agent, suggesting that the molecule is a tetramer formed by the noncovalent association of 13 kDa chains. Isoelectric forms corresponding to isoelectric points of 4.0, 4.2, 5.0, and 5.2 were demonstrable by isoelectric focusing-PAGE, and four active forms having the same isoelectric points were separated by chromatofocusing. The minimal m.w. calculated from amino acid analysis data was 13,193. The protein, denoted KM+, stimulated neutrophil migration in the rat peritoneal cavity assay in a dose-related manner in the range of 1 to 300 micrograms per rat. The dose-response curve of the in vitro chemotactic activity of KM+ was bell shaped and its ascending limb was dose dependent in the range of 1 ng to 10 micrograms/well. D-Mannose (0.1 M) inhibited the in vitro (80%) and in vivo (60%) neutrophil migration-inducing activities of KM+ and also its hemmaglutinating activity. The chemotactic activity was shown to be caused by haptotaxis rather than chemokinesis. The physical and biologic properties of KM+ suggest that this lectin may attract neutrophils by a mechanism involving a haptotactic gradient as has been proposed for IL-8. KM+ might be used as tool to study protein-carbohydrate interactions during neutrophil migration through the extracellular matrix.
Santos-de-Oliveira
R
R
Department of Parasitology, Microbiology, and Immunology, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil.
Dias-Baruffi
M
M
Thomaz
S M
SM
Beltramini
L M
LM
Roque-Barreira
M C
MC
D000596:Amino Acids / Q000737:chemistry; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry* / Q000494:pharmacology; D002634:Chemotaxis, Leukocyte / Q000187:drug effects*; D037102:Lectins / Q000737:chemistry* / Q000494:pharmacology; D008297:Male; D037241:Mannose-Binding Lectins; D008970:Molecular Weight; D009504:Neutrophils / Q000187:drug effects*; D010835:Phytohemagglutinins / Q000737:chemistry* / Q000494:pharmacology; D037121:Plant Lectins; D010940:Plant Proteins / Q000302:isolation & purification* / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012639:Seeds
D000596:Amino Acids; D002352:Carrier Proteins; D037102:Lectins; D037241:Mannose-Binding Lectins; D010835:Phytohemagglutinins; D037121:Plant Lectins; D010940:Plant Proteins