Disease relevance of ITGB2

• In analogy with observations during clinical coliform mastitis, a progressive decrease of CD62L expression levels was observed early after LPS infusion, concomitantly with a continuous rise of CD11b and CD18 density [1].
• Mapping of the binding site for Mannheimia haemolytica leukotoxin within bovine CD18 [2].
• Previously, we identified bovine CD18 as the receptor for leukotoxin secreted by Mannheimia (Pasteurella) haemolytica [3].
• This study tests the effect of a CD18 monoclonal antibody on the hypotension and lung injury after intestinal I/R [4].
• Non-opsonic attachment of Bordetella bronchiseptica mediated by CD11/CD18 and cell surface carbohydrates [5].

High impact information on ITGB2

• Two point mutations were identified within the gene encoding bovine CD18 in a Holstein calf afflicted with leukocyte adhesion deficiency (LAD) [6].
• To map the site involved in Mannheimia haemolytica leukotoxin (LktA) binding and biological activity within bovine CD18, bovine x human CD18 chimeric constructs were generated and coexpressed with bovine CD11a in K562 cells [2].
• LktA-induced TP of the CD18 tail was attenuated by an NRTK inhibitor, herbimycin A; a phosphatidylinositol 3'-kinase (PI 3-kinase) inhibitor, wortmannin; and a Src kinase inhibitor, PP2, in a concentration-dependent manner [7].
• The results demonstrate for the first time that Lkt binds to bovine CD11a and CD18 (lymphocyte function-associated antigen 1 [LFA-1]) [8].
• Factors able to upregulate CD18 expression on peripheral blood neutrophils also appeared in milk at this time [9].

Chemical compound and disease context of ITGB2

• Antibodies to the neutrophil CD18 integrin have been shown to ameliorate the local effects of intestinal ischemia and reperfusion (I/R) [4].
• OBJECTIVE: To determine the effect of mastitis caused by Escherichia coli on expression of CD18 cell surface receptors and to evaluate the involvement and regulation of receptors by lipopolysaccharide (LPS) and cortisol [10].
• Evaluation of the role of endotoxin and cortisol on modulation of CD18 adhesion receptors in cows with mastitis caused by Escherichia coli [10].

Biological context of ITGB2

• We report on a PCR-RFLP procedure for recognising of a silent point mutation of ITGB2 CD18 subunit gene in cattle [11].
• Aggregated bovine (Agg) IgG-induced apoptosis of control neutrophils was not significantly different from that of CD18-deficient neutrophils [12].
• Interestingly, in contrast to coliform mastitis, the net CD18 variation is not principally influenced by CD11b upregulation during endotoxin administration [1].
• However, no correlation was found between the kinetics of CD11b and CD18 density [1].
• Our results indicate that LktA induces tyrosine phosphorylation (TP) of the CD18 tail of LFA-1 in bovine leukocytes [7].

Anatomical context of ITGB2

• Viability was markedly decreased in control neutrophils stimulated with opsonized zymosan (OPZ), compared to CD18-deficient neutrophils at 37 degrees C after incubation periods of 6 and 24 hours [12].
• At the developmental stage, corpora lutea exhibited many CD18-positive cells in the septa [13].
• As detected by immunolocalization, macrophage-like cells of various sizes showed a response for the CD18 surface molecule of leukocytes, for the CD45 molecule related to hemopoietic progenitor cells, and for the CD14 molecule selectively expressed on cells of the monocyte-macrophage lineage [14].
• Cortisol induces a decrease in the number of CD18 receptors, probably modulating the acute inflammatory response in mammary glands of lactating cows [10].
• Deficient CD18 expression on lymphocytes and mononuclear phagocytes from cattle with BLAD was clearly detected by use of flow cytometric analysis [15].

Associations of ITGB2 with chemical compounds

• The bovine cDNA (CD18) encoding CD18, a cell-surface glycoprotein involved in multiple leukocyte functions, was sequenced and compared with the human and murine sequences [16].
• The aim of this in vivo study was to examine the effect of intramammarily administered endotoxin (lipopolysaccharide, LPS) on the expression of L-selectin (CD62L) and the beta2-integrin subunits CD11b and CD18 on circulating bovine PMN [1].
• However, at no time during the experiment did dexamethasone influence the proportion of gated cells staining positive for CD18 (always 100%) [17].
• Immunostaining was performed on whole blood (100 microliters) that was left unstimulated or was stimulated with platelet-activating factor (PAF; 1 microgram/ml blood) prior to incubation with fluorescein isothiocyanate-conjugated monoclonal antibodies against L-selectin and CD18 [17].
• A monoclonal antibody specific for the leukocyte integrin polypeptide CD18 partially inhibited attachment of B. bronchiseptica to normal PMN but not to PMN genetically deficient in CD11/CD18 integrins [5].

Other interactions of ITGB2

• No apparent increase in annexin V expression on CD18-deficient neutrophils was found with OPZ stimulation [12].

Analytical, diagnostic and therapeutic context of ITGB2

• Since the overall leucocyte distribution has not been studied in the bovine ovary, we located the CD18 molecule in this organ using indirect immunohistochemistry [13].
• PROCEDURE: Constitutive CD18 and CD62L expression on neutrophils was determined by flow cytometry, using specific monoclonal antibodies [18].
• There was, however, a significant reduction (P < 0.01) in the intensity of CD18 expression on lymphocytes in the treated animals on the fourth day after treatment [19].
• Lymphocyte blastogenesis in response to ConA and the percentages of lymphocytes positive for CD2, CD4, CD8, CD49d and CD18 as well as the intensity of CD49d expression did not differ between the treatment and control groups [19].
• A 101 bp fragment from the polymorphic region of CD18 gene located on chromosome 1 was amplified by PCR [20].

References