Molecular expression of the alpha-chemokine rabbit GRO in Escherichia coli and characterization of its production by lung cells in vitro and in vivo.
GRO proteins are alpha-chemokine cytokines that attract neutrophils and stimulate the growth of a variety of cells. Previously, we observed that rabbit alveolar macrophages transcribe the genes for at least two GRO homologues. In order to study the role of GRO cytokines in lung inflammation, we cloned the predominant rabbit GRO cDNA (RabGRO) from alveolar macrophages, expressed bioactive recombinant protein (rRabGRO) in Escherichia coli, and developed a sensitive and specific enzyme-linked immunosorbent assay for RabGRO protein. We found that rabbit AM express and secrete GRO in vitro in response to both exogenous (e.g. lipopolysaccharide, heat-killed Staphylococcus aureus, and crystalline silica) and endogenous inflammatory stimuli (e.g. tumor necrosis factor-alpha) as determined by both radioimmunoprecipitation and enzyme-linked immunosorbent assay. Biologically significant amounts of GRO are present in vivo in the bronchoalveolar lavage fluid of rabbits with E. coli pneumonia; by in situ hybridization, GRO mRNA is detectable in infiltrating pulmonary leukocytes and bronchial epithelial cells. These results indicate that GRO chemokines are likely to be important mediators of the inflammatory response that accompanies acute infectious processes in the lungs.
Johnson
M C
MC
Medical Research Service, Seattle Veterans Affairs Medical Center, Washington 98108, USA.
Kajikawa
O
O
Goodman
R B
RB
Wong
V A
VA
Mongovin
S M
SM
Wong
W B
WB
Fox-Dewhurst
R
R
Martin
T R
TR
D000818:Animals; D001483:Base Sequence; D001992:Bronchoalveolar Lavage Fluid; D054360:Chemokine CXCL1; D018925:Chemokines / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D019743:Chemokines, CXC; D002630:Chemotactic Factors / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D002634:Chemotaxis, Leukocyte; D017931:DNA Primers; D004926:Escherichia coli / Q000235:genetics / Q000472:pathogenicity; D005260:Female; D006133:Growth Substances / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D036341:Intercellular Signaling Peptides and Proteins; D008168:Lung / Q000378:metabolism* / Q000473:pathology; D016676:Macrophages, Alveolar / Q000166:cytology; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009504:Neutrophils / Q000166:cytology; D018410:Pneumonia, Bacterial / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D011817:Rabbits
C475829:CXCL1 protein, human; D054360:Chemokine CXCL1; D018925:Chemokines; D019743:Chemokines, CXC; D002630:Chemotactic Factors; C475895:Cxcl1 protein, mouse; D017931:DNA Primers; D006133:Growth Substances; D007074:Immunoglobulin G; D036341:Intercellular Signaling Peptides and Proteins