Introduction
beta-integrin (CD11/CD18) family plays an important role in inflammation via their regulatory effects on leukocyte adhesion, transmigration, and function. PMID: 11140880
CD11a/CD18 is a lymphocyte function-associated antigen-1, and CD11b/CD18 is a macrophage antigen-1. Both are present on neutrophils/macrophages. PMID: 15255256
The CD11/CD18 integrins are transmembrane proteins. Like CD14, they are capable of mediating LPS-induced cellular activation when expressed on the surface of hamster fibroblasts Chinese hamster ovary (CHO)-K1. PMID: 9820516
Normal Expression
Chinese hamster ovary (CHO) fibroblast cell lines expressing the CD11a/CD18 or CD11b/CD18 antigen were engineered by gene transfection. PMID: 9441798
CD11a/CD18 are apparent on early progenitors of all myeloid and erythroid cells. CD11b/CD18 and CD11c/CD18 are more restricted antigens normally expressed on monocytes, macrophages, PMN and natural killer cells. Activated granulocytes and monocytes express far more CD11b/CD18 than the other two antigens: 6 to 8 x 10(5) CD11b/CD18 molecules appear on maximally activated granulocytes PMID: 7628754
Indirect immunoperoxidase staining patterns indicated that intratracheal challenge with beads activated BAL cells and upregulated expression of CD11b, ICAM-1, and CD18 antigenic markers on macrophages and neutrophils when compared with BAL cells from saline controls. Immunohistochemical staining also confirmed the presence of CD11b on activated macrophages and neutrophils around the beads and of the ICAM-1 antigen in the lung parenchyma of bead challenged mice. PMID: 7955560
The anti-CD11/CD18 monoclonal antibodies (mAbs) submitted in the Second International Workshop on Ruminant Leukocyte Differentiation Antigens, were analysed for their reactivity with the ovine homologue of CD11/CD18. Their reactivity was tested on healthy sheep tissues, and alveolar macrophages, afferent dendritic cells, peripheral blood granulocytes and monocytes. The CD11a/CD18 mAbs found positive in the sheep were reactive with all the cell populations tested. The CD11b mAbs reacted with all the cells except afferent dendritic cells, whereas CD11c were non-reactive to blood granulocytes. This is in contrast to humans and cattle where blood granulocytes express CD11c. PMID: 8310662
CD11 antigens appeared to be strongly expressed only on mature granulocytes, monocytes, and certain lymphocytes, but not significantly on myeloid committed precursor cells. Surprisingly, CD11 antigens were weakly, but significantly, present on CFU-E. PMID: 3002833
In this report, we demonstrate that 9.3- lymphocytes express CD11, an antigen which is also present on monocytes and granulocytes. PMID: 3936719
Abnormal Expression
The expression of the CD18 integrin on Neutrophil (PMN) obtained from the pulmonary vascular lavage (PVL) of C. parvum-treated animals was increased compared with cells from control animals. PMID: 7576688
the number of alveolar macrophages (AM) expressing CD11/CD18 molecules is increased in smokers compared with nonsmokers and related to the superoxide anion (O2-) production of these cells. PMID: 7735614
The mean fluorescence of CD18 on lymphocytes and CD11c on monocytes of HIV-1-infected subjects was significantly higher than for the control group (P = .008 and .014, respectively). PMID: 7916028
increased peripheral phagocyte CD11/CD18 expression is a feature of Tuberculosis (TB), which may contribute to the pathological processes involved. PMID: 7518366
The beta 2 integrin CD11a (Leu-CAMa, LFA-1) was detected on some B-cell clones and seemed to relate to tissue localization of the disease. T and NK cells showed a low expression of CD11a in B-CLL patients, while in B-MLUS a high proportion of non-clonal cells coexpressed CD11a with a high staining intensity. The relative numbers of both CD18+ as well as CD2+ cells showed a positive correlation with phorbol ester induced cell aggregation in B-MLUS patients (p < 0.05). PMID: 7519509
Compared with nonsmokers, the samples from sarcoidosis (SA) and idiopathic pulmonary fibrosis (IPF) patients contained an increased number of AM expressing CD11a, CD11b, CD11c, and CD18 (all p < 0.008), which was correlated to the number of AM/ml BAL (p < 0.008). PMID: 8099261
Using a novel method for the preparation of blood leucocytes for flow cytometry, we report increased expression of LeuCAMs (CD11/CD18) on peripheral blood leucocytes of 11 Caucasian and 10 Afro-Caribbean patients with sarcoidosis compared with age-, sex- and race-matched controls. PMID: 1356670
Cell surface expression of CD11a and CD18, but not ICAM-1, was increased on HIV-infected, as compared to uninfected U937 and THP1 monocytoid cells. PMID: 2576928
Function
CD11b might be involved at least in part in the process of fungal dissemination from lung to brain. PMID: 12008927
CD11 molecule is useful for distinguishing novel subsets of T8 cells. PMID: 2962748
Applications
Flow Cytometry (FC)
we measured the expression of CD11/CD18 glycoproteins and the oxidative burst of PMNs in patients with polycythemia vera (PV) (13) and essential thrombocythemia (ET) (18) and in 15 healthy voluntary donors. Experiments were performed by flow cytometry in total blood. PMID: 12145463
Polymorphonuclear (PMN) cell activation in the presence of synthetic vascular grafts was studied by using flow cytometry to measure CD11/CD18 leukocyte adhesion molecule expression at the cell surface. PMID: 8555588
Here we have studied the expression of CD11/CD18 and CD29 (VLA beta 1 integrin) on the peripheral blood leucocytes of 10 TB patients by flow cytometry. PMID: 7518366
Using a novel method for the preparation of blood leucocytes for flow cytometry, we report increased expression of leucocyte adhesion molecules (LeuCAMs) (CD11/CD18) on peripheral blood leucocytes of patients with HIV disease compared with normal controls. PMID: 8103716
The expression of the CD11 and CD18 glycoproteins on a wide variety of rabbit leucocyte populations has been investigated by flow cytometry. PMID: 8098131
We also evaluated the functional and immunochemical activities of five monoclonal antibodies (MoAbs) reactive with the CD11/CD18 leucocyte adhesion molecules of granulocytes. PMID: 8096150
We have used three-color flow cytometry to investigate the pattern of expression of the CD11/CD18, CD44, and leukocyte adhesion molecule 1 (LAM-1) adhesion molecules during myeloid and erythroid differentiation in humans. PMID: 1702327
We have studied the expression of Fc gamma receptors and leucocyte integrins (CD11/CD18 family) on human eosinophils using specific monoclonal antibodies (mAb) and flow cytometric analysis. PMID: 1968426
CD11a, CD18, and ICAM-1 were demonstrated on up to 80% of HIV-1-infected H9 T cells by flow cytometry. PMID: 2576928
Immunofluorescence (IF)
Here, in an immunofluorescence analysis, we have examined CD11/CD18 glycoprotein expression by human monocytes, pulmonary alveolar macrophages (PAM, obtained by bronchoalveolar lavage), and breast milk macrophages (BMM) as compared to neutrophils before and after exposure to A23187 (1 microM), fMLP (0.1 microM), or PMA (0.1 microgram/ml) for 15 min at 37 degrees C. PMID: 3123109
Immunohistochemistry (IHC)
This study examined the mechanisms through which this sequestration occurs, as well as the effect of complement fragments on the expression of L-selectin and CD11/CD18 using ultrastructural immunohistochemistry. PMID: 9872849
Indirect immunoperoxidase staining patterns indicated that intratracheal challenge with beads activated BAL cells and upregulated expression of CD11b, ICAM-1, and CD18 antigenic markers on macrophages and neutrophils when compared with BAL cells from saline controls. Immunohistochemical staining also confirmed the presence of CD11b on activated macrophages and neutrophils around the beads and of the ICAM-1 antigen in the lung parenchyma of bead challenged mice. PMID: 7955560
Western Blot (WB)
Western blot assays showed that the fimbriae bound to molecules of beta2 integrin (CD11/CD18) on the macrophages. PMID: 9712747