Expression Of Milk Fat Globule Epidermal Growth Factor 8 Research Articles

Expression and clinical association of MFG-E8 and TAM receptors in diabetic patients with different stages of microvascular complication: An experimental study.

Diabetic nephropathy (DN) is a major microvascular complication of diabetes mellitus that leads to end-stage renal disease. Hyperglycemia triggers apoptosis and kidney damage. Milk fat globule-epidermal growth factor 8 (MFG-E8) and TAM receptor tyrosine kinases, Tyro3, Axl, and Mer, are phagocytic receptors that mediate the clearance of apoptotic cells. This study aimed to identify the role of MFG-E8 and TAM receptors in the development of DN. A total of 146 patients with type 2 diabetes mellitus (T2DM), early stage DN, clinical DN and 48 healthy controls were employed to analyze the serum levels of MFG-E8, soluble Tyro3, Axl, Mer, and RAGE by enzyme-linked immunosorbent assay. The serum levels of CREA, hsCRP, CysC, and β2-microglobulin were measured by spectrophotometric analysis using a biochemical analyzer (AU5800). Our results showed that the serum levels of MFG-E8 were elevated in patients with T2DM compared with healthy controls; however, it decreased gradually in patients with DN with the severity of kidney injury, especially in the clinical DN group. Moreover, the levels of sTyro3, sAxl, and sMer were reduced in patients with T2DM and DN compared to healthy controls, particularly in patients with DN. The levels of MFG-E8, sTyro3, sAxl, and sMer were negatively correlated with UAER at 24 hours, CREA, hsCRP, CysC, β2-microglobulin, and RAGE, respectively. In addition, TAM receptors had significantly higher predictive and diagnostic values for early stage DN from T2DM than hsCRP, β2-microglobulin, and CysC, which are also predictive biomarkers of early stage DN from clinical DN. Decreased MFG-E8 and TAM receptor expression is associated with an increased risk of microvascular complications in patients with T2DM, which plays a critical role in the diagnosis of diabetic patients with microvascular complications, especially early stage DN, and in monitoring the development of DN.

MFG-E8 has guiding significance for the prognosis and treatment of sepsis

Sepsis remains a significant clinical challenge. Ferroptosis is involved in the pathogenesis of sepsis. Ferroptosis is associated with oxidative stress, and excessive oxidative stress is suppressed by milk fat globule epidermal growth factor 8 (MFG-E8) under various conditions. However, the role of MFG-E8 in sepsis-induced ferroptosis and oxidative stress is still unclear. First, we collected blood samples from patients with sepsis and detected the expression of serum MFG-E8. Then, the relationship between serum concentrations of MFG-E8 and disease severity was detected. Finally, the effects of MFG-E8 treatment on ferroptosis and oxidative stress in the livers of septic mice were determined. The expression of serum MFG-E8 in healthy subjects was notably higher than that in septic patients. In addition, when nonsurvivors and survivors of sepsis were compared, MFG-E8 levels were considerably lower in the former. The ROC curve for MFG-E8 was also generated. The area under the curve for MFG-E8 was 0.768 (95% confidence interval [CI] 0.627–0.909, p = 0.003). The patients were separated into two groups based on the MFG-E8 cut-off value of 3.86 ng/mL. According to the Kaplan‒Meier survival analysis, patients with low MFG-E8 levels had a significantly decreased 28-day survival rate compared with patients with high MFG-E8 levels. High MFG-E8 levels were substantially related to a decreased risk of death, as demonstrated by the Cox proportional hazard model that we utilized. In addition, compared with sham mice, septic mice exhibited liver and kidney damage, and MFG-E8 may have protective effects. The survival study indicated that MFG-E8 could effectively improve the survival rate of septic mice. Treatment with MFG-E8 suppresses oxidative stress and ferroptosis in the livers of septic mice. Serum MFG-E8 levels are lower in septic patients and are negatively related to disease severity. Treatment with MFG-E8 suppresses oxidative stress and ferroptosis in the livers of septic mice, contributing to significantly improved survival in septic mice. These findings showed that MFG-E8 could be a new sepsis predictive biomarker. MFG-E8 may have therapeutic potential in the treatment of sepsis.

High Levels of MFG-E8 Confer a Good Prognosis in Prostate and Renal Cancer Patients

Simple SummaryIn the present study, we analyzed the distribution and prognostic impact of milk fat globule-epidermal growth factor-8 (MFG-E8) protein expression in patients with prostate and renal cancers. Our data highlighted MFG-E8 expression by tumor cells in the epithelium. Our results also showed that low levels of MFG-E8 in prostate and renal cancers were associated with worse clinical outcomes. Furthermore, higher numbers of CD206+ cells were found in the peripheral regions of renal clear cell carcinoma that expressed lower MFG-E8 levels. Globally, our results suggest that MFG-E8 expression could potentially be used as a prognostic marker in prostate and renal cancers.Milk fat globule-epidermal growth factor-8 (MFG-E8) is a glycoprotein secreted by different cell types, including apoptotic cells and activated macrophages. MFG-E8 is highly expressed in a variety of cancers and is classically associated with tumor growth and poor patient prognosis through reprogramming of macrophages into the pro-tumoral/pro-angiogenic M2 phenotype. To date, correlations between levels of MFG-E8 and patient survival in prostate and renal cancers remain unclear. Here, we quantified MFG-E8 and CD68/CD206 expression by immunofluorescence staining in tissue microarrays constructed from renal (n = 190) and prostate (n = 274) cancer patient specimens. Percentages of MFG-E8-positive surface area were assessed in each patient core and Kaplan–Meier analyses were performed accordingly. We found that MFG-E8 was expressed more abundantly in malignant regions of prostate tissue and papillary renal cell carcinoma but was also increased in the normal adjacent regions in clear cell renal carcinoma. In addition, M2 tumor-associated macrophage staining was increased in the normal adjacent tissues compared to the malignant areas in renal cancer patients. Overall, high tissue expression of MFG-E8 was associated with less disease progression and better survival in prostate and renal cancer patients. Our observations provide new insights into tumoral MFG-E8 content and macrophage reprogramming in cancer.

Protective Effect of MFG-E8 on Necroptosis-Induced Intestinal Inflammation and Enteroendocrine Cell Function in Diabetes

Low-grade inflammation is one of the characteristics of metabolic disorders induced by diabetes mellitus. The present study explores the underlying mechanism of milk fat globule epidermal growth factor 8 (MFG-E8) on necroptosis-induced intestinal inflammation and intestinal epithelial endocrine cell dysfunction in diabetes. Compared with the normal control group, pathological changes such as blunt and shortened villus and denuded villus tips were observed in ileum tissue of streptozotocin (STZ) induced senescence-resistant 1 (SAMR1) and senescence-accelerated prone 8 (SAMP8) diabetic mice under light microscope. Western blotting and immunohistochemistry (IHC) displayed significantly decreased protein expression of MFG-E8 in SAMR1 and SAMP8 diabetic mice, accompanied by an increased expression of phosphorylated mixed lineage kinase domain-like (p-MLKL) and HMGB1. In addition, advanced glycation end products (AGEs) significantly increased the pro-inflammatory mediators (TNF-α, IL-1β, IL-6) and HMGB1 by activating the receptor-interacting protein kinase 3 (RIPK3)/MLKL signaling pathway in enteroendocrine STC-1 cells. D-pinitol pretreatment markedly attenuated the release of pro-inflammatory mediators and increased the expression of MFG-E8. MFG-E8 small interfering RNA (siRNA) promoted, while MFG-E8 overexpression inhibited, the activation of receptor-interacting proteins (RIPs) pathway and pro-inflammatory factors. Our study demonstrated that downregulation of MFG-E8 is an important phenomenon in the pathogenesis of diabetes-related intestinal inflammatory damage. MFG-E8 overexpression and D-pinitol intervention could protect against necroptosis-induced intestinal inflammation and maintain the function of enteroendocrine STC-1 cells in diabetes.

DCI after Aneurysmal Subarachnoid Hemorrhage Is Related to the Expression of MFG-E8.

Objective To explore the predictive value of milk fat globule epidermal growth factor 8 (MFG-E8) in the occurrence of delayed cerebral ischemia (DCI) after an aneurysmal subarachnoid hemorrhage (aSAH). Methods We recruited 32 patients with aSAH as the case group and 24 patients with unruptured aneurysms as the control group. Serum MFG-E8 levels were measured by western blot and enzyme-linked immunosorbent assay. We analyzed the relationship between MFG-E8 levels and the risk of DCI. Results The levels of serum MFG-E8 in the case group (mean = 11160.9 pg/mL) were significantly higher than those in the control group (mean = 3081.0 pg/mL, p < 0.001). MFG-E8 levels highly correlated with the World Federation of Neurosurgical Societies (WFNS) and modified Fisher scores (r = −0.691 and − 0.767, respectively, p < 0.001). In addition, MFG-E8 levels in patients with DCI (5882.7 ± 3162.4 pg/mL) were notably higher than those in patients without DCI (15818.2 ± 3771.6 pg/mL, p < 0.001). A receiver operating characteristic curve showed that the occurrence of DCI could effectively be predicted by MFG-E8 (area under the curve = 0.976, 95%CI = 0.850–1.000). Kaplan–Meier survival analysis showed a remarkable decrease in the incidence of DCI in case group individuals with high levels of MFG-E8 (≥11160.9 pg/mL, p < 0.001). Conclusion MFG-E8 may be a useful predictive marker for DCI after an aSAH and could be a promising surrogate end point.

MFG-E8 attenuates inflammation in subarachnoid hemorrhage by driving microglial M2 polarization

Increasing evidence suggests that microglial polarization plays an important role in the pathological processes of neuroinflammation following subarachnoid hemorrhage (SAH). Previous studies indicated that milk fat globule-epidermal growth factor-8 (MFG-E8) has potential anti-apoptotic and anti-inflammatory effects in cerebral ischemia. However, the effects of MFG-E8 on microglial polarization have not been evaluated after SAH. Therefore, the aim of this study was to explore the role of MFG-E8 in anti-inflammation, and its effects on microglial polarization following SAH. We established the SAH model via prechiasmatic cistern blood injection in mice. Double-immunofluorescence staining, western blotting and quantitative real-time polymerase chain reaction (q-PCR) were performed to investigate the expression and cellular distribution of MFG-E8. Two different dosages (1 and 5 μg) of recombinant human MFG-E8 (rhMFG-E8) were injected intracerebroventricularly (i.c.v.) at 1 h after SAH. Brain water content, neurological scores, beam-walking score, Fluoro-Jade C (FJC), and terminal deoxynucleotidyl transferase dUTP nick endlabeling staining (TUNEL) were measured at 24 h. Suppression of MFG-E8, integrin β3 and phosphorylation of STAT3 were achieved by specific siRNAs (500 pmol/5 μl) and the STAT3 inhibitor Stattic (5 μM). The potential signaling pathways and microglial polarization were measured by immunofluorescence labeling and western blotting. SAH induction increased the levels of inflammatory mediators and the proportion of M1 cells, and caused neuronal apoptosis in mice at 24 h. Treatment with rhMFG-E8 (5 μg) remarkably decreased brain edema, improved neurological functions, reduced the levels of proinflammatory factors, and promoted the microglial to shift to M2 phenotype. However, knockdown of MFG-E8 and integrin β3 via siRNA abolished the effects of MFG-E8 on anti-inflammation and M2 phenotype polarization. The STAT3 inhibitor Stattic further clarified the role of rhMFG-E8 in microglial polarization by regulating the protein levels of the integrin β3/SOCS3/STAT3 pathway. rhMFG-E8 inhibits neuronal inflammation by transformation the microglial phenotype toward M2 and its direct protective effect on neurons after SAH, which may be mediated by modulation of the integrin β3/SOCS3/STAT3 signaling pathway, highlighting rhMFG-E8 as a potential therapeutic target for the treatment of SAH patients.

Milk fat globule epidermal growth factor 8 (MFG-E8) on monocytes is a novel biomarker of disease activity in systemic lupus erythematosus.

Milk fat globule epidermal growth factor (MFG-E8) is related secreted protein which links phosphatidylserine on apoptotic cells and integrin αvβ3/5 on phagocytes. To clarify the clinical significance of MFG-E8 in SLE, we analyzed the correlation between expression level of MFG-E8 in circulating phagocytic leukocytes and clinical parameters of patients. The study was conducted under a multi-center, prospective cohort design. Patients with one or both BILAG A or B, or SLEDAI- 2 K ≥ 4 with clinical symptoms were defined as the active SLE group. Expression of MFG-E8 on monocytes and concentration in serum were measured by FACS and ELISA, respectively. 96 subjects were enrolled. The absolute number and proportion of MFG-E8-positive monocytes to total monocytes were significantly higher in the active SLE group (p < 0.01). Importantly, the proportion was also significantly correlated with SLEDAI-2K, clinical SLEDAI, as well as serum levels of anti-ds-DNA antibody and complement and C1q. In addition, the proportion of MFG-E8-positive monocytes to total monocytes was significantly decreased from baseline in active SLE patients after 6 months' treatment and increased concordantly with disease activity in 6 refractory cases. Further, in receiver operating characteristic curve analysis for discrimination between active and inactive SLE, the AUC of the proportion of MFG-E8 was 0.854, which was equivalent to classical activity markers such as anti-ds DNA antibody (0.776), complement (0.897) and C1q (0.815). The proportion of MFG-E8-positive monocytes to total monocytes in peripheral blood was positively associated with disease activity in SLE and may be a novel biomarker of disease activity.

Construction of short hairpin RNA interfering milk fat globule-epidermal growth factor 8 gene lentiviral vector and its effect on inhibition of breast cancer cells

Objective To construct the lentiviral vector of milk fat globule-epidermal growth factor 8 (MFG-E8) short hairpin RNA (shRNA), and stably transfected the HCC1973 cell line to detect its interference efficiency and influence in breast cancer cell HCC1973. Methods The knockout gene fragment was synthesized and inserted into the shRNA lentiviral vector PLKO.1 with a cherry protein reporter. The constructed recombinant plasmids were transfected into 293T cells respectively. The lentiviruses were transfected into HCC1973 cells and stably transfected PLKO.1-MFG-E8 shRNA recombinant lentiviruses were obtained. The expression of MFG-E8 was detected by real-time PCR and Western blotting. The cell proliferation was measured by methyl thiazol tetrazolium (MTT) assay and Flow cytometry was used to detect the cell cycle and apoptosis, Transwell was used to detect the invasion and migration of cells. Statisticalanalysis of data using the statistical product and service solutions 17.0 software. Results The constructed vector of PLKO.1-MFG-E8 shRNA significantly reduced the expression of MFG-E8 gene and protein in breast cancer cell HCC1973, the lentivirus titer was 3×108 PFU/ml. The proliferation of breast cancer cells was significantly suppressed (t=4.426, P<0.05), G0/G1 phase cells increased significantly with a decrease of cells in S phase (t=2.264, P<0.05), the ability of cell invasion and migration was significantly reduced (t=4.802, P<0.05), after the lentiviral infection. Conclusion The expression of MFG-E8 gene and protein by shRNA interference can inhibit the malignant biological behavior of breast cancer cells effectively, which indicates that MFG-E8 is involved in the invasion, metastasis and apoptosis of breast cancer during the process of breast carcinogenesis. Key words: Milk fat globule-epidermal growth factor 8 short hairpin RNA; Cell cycle; Cell proliferation; Cell poptosis; Invasion and metastasis

Milk-fat globule epidermal growth factor 8 (MFGE8) is expressed at the embryo- and fetal-maternal interface in equine pregnancy.

Milk-fat globule epidermal growth factor (EGF) 8 protein (MFGE8), also known as lactadherin, promotes cell adhesion in an Arg-Gly-Asp (RGD)-dependent modus via integrins. In the present study, the expression of MFGE8 was examined in equine endometrium during oestrus and at Days 12 and 16 after ovulation in pregnant and non-pregnant mares and in mares during the 5th month of gestation. Results demonstrated that MFGE8 is expressed at the embryo- and fetal-maternal interface in equine pregnancy. In non-pregnant endometrium its expression was upregulated by oestrogen, a finding that was confirmed using endometrial explant culture. MFGE8 was expressed at similar levels by conceptuses collected 13 and 14 days after ovulation and by allantochorion sampled during the 5th month of gestation. Pericytes of endometrial blood vessels displayed strong MFGE8 expression upon in situ hybridisation. During the 5th month of gestation, the fetal side of the allantochorionic villi in particular displayed pronounced staining upon in situ hybridisation, confirming that MFGE8 expression is not restricted to early pregnancy but persists and is present at the fetal-maternal interface. Potential roles of MFGE8 in equine pregnancy include mediating cell-cell adhesion, promotion of angiogenesis and placental transfer of fatty acids.

Role of milk fat globule-epidermal growth factor 8 in osteoimmunology.

Milk fat globule-epidermal growth factor 8 (MFG-E8) is a glycoprotein that is abundantly expressed in various tissues and has a pivotal role in the phagocytic clearance of apoptotic cells. However, MFG-E8 has also gained significant attention because of its wide range of functions in autoimmunity, inflammation and tissue homeostasis. More recently, MFG-E8 has been identified as a critical regulator of bone homeostasis, being expressed in both, osteoblasts and osteoclasts. In addition, it was shown that MFG-E8 fulfils an active role in modulating inflammatory processes, suggesting an anti-inflammatory role of MFG-E8 and proposing it as a novel therapeutic target for inflammatory diseases. This concise review focusses on the expression and regulation of MFG-E8 in the context of inflammatory bone diseases, highlights its role in the pathophysiology of osteoimmune diseases and discusses the therapeutic potential of MFG-E8.

MFG-E8, a clearance glycoprotein of apoptotic cells, as a new marker of disease severity in chronic obstructive pulmonary disease.

Milk fat globule epidermal growth factor 8 (MFG-E8) is an opsonin involved in the phagocytosis of apoptotic cells. In patients with chronic obstructive pulmonary disease (COPD), apoptotic cell clearance is defective. However, whether aberrant MFG-E8 expression is involved in this defect is unknown. In this study, we examined the expression of MFG-E8 in COPD patients. MFG-E8, interleukin (IL)-1β and transforming growth factor (TGF)-β levels were measured in the plasma of 96 COPD patients (93 males, 3 females; age range: 62.12±10.39) and 87 age-matched healthy controls (85 males, 2 females; age range: 64.81±10.11 years) using an enzyme-linked immunosorbent assay. Compared with controls, COPD patients had a significantly lower plasma MFG-E8 levels (P<0.01) and significantly higher plasma TGF-β levels (P=0.002), whereas there was no difference in plasma IL-1β levels between the two groups. Moreover, plasma MFG-E8 levels decreased progressively between Global Initiative for Chronic Obstructive Lung Disease (GOLD) I and GOLD IV stage COPD. Multiple regression analysis showed that the forced expiratory volume in 1 s (FEV1 % predicted) and smoking habit were powerful predictors of MFG-E8 in COPD (P<0.01 and P=0.026, respectively). MFG-E8 was positively associated with the FEV1 % predicted and negatively associated with smoking habit. The area under the receiver operating characteristic curve was 0.874 (95% confidence interval: 0.798-0.95; P<0.01). Our findings demonstrated the utility of MFG-E8 as a marker of disease severity in COPD and that cigarette smoke impaired MFG-E8 expression in these patients.

Milk Fat Globule-Epidermal Growth Factor 8 (MFG-E8) Is a Novel Anti-inflammatory Factor in Rheumatoid Arthritis in Mice and Humans.

Milk fat globule-epidermal growth factor 8 (MFG-E8) is an anti-inflammatory glycoprotein that mediates the clearance of apoptotic cells and is implicated in the pathogenesis of autoimmune and inflammatory diseases. Because MFG-E8 also controls bone metabolism, we investigated its role in rheumatoid arthritis (RA), focusing on inflammation and joint destruction. The regulation of MFG-E8 by inflammation was assessed in vitro using osteoblasts, in arthritic mice and in patients with RA. K/BxN serum transfer arthritis (STA) was applied to MFG-E8 knock-out mice to assess its role in the pathogenesis of arthritis. Stimulation of osteoblasts with lipopolysaccharide (LPS) and tumor necrosis factor (TNF)-α downregulated the expression of MFG-E8 by 30% to 35%. MFG-E8-deficient osteoblasts responded to LPS with a stronger production of pro-inflammatory cytokines. In vivo, MFG-E8 mRNA levels were 52% lower in the paws of collagen-induced arthritic (CIA) mice and 24% to 42% lower in the serum of arthritic mice using two different arthritis models (CIA and STA). Similarly, patients with RA (n = 93) had lower serum concentrations of MFG-E8 (-17%) compared with healthy controls (n = 140). In a subgroup of patients who had a moderate to high disease activity (n = 21), serum concentrations of MFG-E8 rose after complete or partial remission had been achieved (+67%). Finally, MFG-E8-deficient mice subjected to STA exhibited a stronger disease burden, an increased number of neutrophils in the joints, and a more extensive local and systemic bone loss. This was accompanied by an increased activation of osteoclasts and a suppression of osteoblast function in MFG-E8-deficient mice. Thus, MFG-E8 is a protective factor in the pathogenesis of RA and subsequent bone loss. Whether MFG-E8 qualifies as a novel biomarker or therapeutic target for the treatment of RA is worth addressing in further studies.

Prolactin induces MFG-E8 production in macrophages via transcription factor C/EBPβ-dependent pathway

The lactogenic hormone prolactin (PRL) regulates milk protein gene expression in mammary glands. To maintain homeostatic balance in the body, milk fat globule epidermal growth factor 8 (MFG-E8) is vital for phagocytic clearance of apoptotic cells. We investigated the effects of PRL on MFG-E8 expression in macrophages by evaluating its promoter function. Macrophages were stimulated with PRL, and the expression of MFG-E8 was determined using real-time PCR and Western blotting. The role of MFG-E8 on phagocytosis of apoptotic cells in PRL-treated macrophages was assessed using microscopy, while the response of PRL to MFG-E8 expression was evaluated using luciferase assay. Following treatment with PRL, significant up-regulations of the PRL receptor and MFG-E8 were observed in macrophages, though PRL-treated macrophages more efficiently engulfed apoptotic cells. The results of MFG-E8 promoter analysis showed considerable up-regulation of promoter activity in macrophages following PRL treatment and results from mutation analysis of the MFG-E8 promoter suggested that the C/EBPbeta binding site was responsible for PRL-induced activation of the MFG-E8 promoter. C/EBPbeta activity was found to be up-regulated in PRL-treated cells as revealed by an electrophoretic mobility shift assay (EMSA). In conclusion, PRL is a potent inducer of MFG-E8 expression in macrophages, while its effect is mediated by the presence of a responsive element in the MFG-E8 promoter.

Milk fat globule EGF factor 8 in the serum of human patients of systemic lupus erythematosus

Mouse milk fat globule epidermal growth factor 8 (MFG-E8), which is secreted by a subset of activated macrophages, binds to apoptotic cells by recognizing phosphatidylserine and promotes their engulfment. Many apoptotic cells are left unengulfed in the germinal centers of the spleen in MFG-E8(-/-) mice, and these mice develop an autoimmune disease resembling human systemic lupus erythematosus (hSLE). Here, we report that hMFG-E8 bound to phosphatidylserine and an integrin alpha(v)beta(3) complex. Increasing concentrations of MFG-E8 generated a bell-shaped response curve for the efficiency of phagocytosis. That is, in NIH3T3 and MFG-E8(-/-) thioglycollate-elicited peritoneal macrophages that do not express MFG-E8, hMFG-E8 enhanced engulfment at low concentrations but inhibited it at high concentrations. On the other hand, hMFG-E8 dose-dependently inhibited the engulfment of apoptotic cells by MFG-E8(+/+) thioglycollate-elicited peritoneal macrophages, indicating that an excess of MFG-E8 has an inverse effect on the engulfment of apoptotic cells. To investigate the role of MFG-E8 in human disease, we generated two mAb against MFG-E8 and screened human blood samples for MFG-E8 using an ELISA. We found that some childhood-onset and adult SLE patients carried a significant level of MFG-E8 in their blood samples. These results suggested that the aberrant expression of MFG-E8 is involved in the pathoetiology of some cases of hSLE.

Expression of milk fat globule epidermal growth factor 8 in immature dendritic cells for engulfment of apoptotic cells

Milk fat globule epidermal growth factor 8 (MFG-E8) is a protein that stimulates the engulfment of apoptotic cells by phagocytes. Here, we show that mouse immature dendritic cells (DC) generated in vitro by culturing bone marrow progenitors in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF), and Langerhans cells present in the skins, expressed MFG-E8. Bone marrow-derived macrophages generated by M-CSF did not express MFG-E8. MFG-E8 expressed in immature DC was found to be secreted as exosomes. The expression of MFG-E8 was significantly suppressed when the immature DC were induced to mature by treating them with lipopolysaccharides. This expression of MFG-E8 was well correlated with the ability of the cells to engulf apoptotic cells. That is,immature DC phagocytosed apoptotic cells more efficiently than did mature DC or bone marrow-derived macrophages. The ability of immature DC to engulf apoptotic cells was severely reduced when the immature DC were prepared from MFG-E8-deficient mice. These results indicated that MFG-E8 plays an essential role in the engulfment of apoptotic cells by bone marrow-derived immature DC.