Tryptase-Positive Mast Cells Promote Adipose Fibrosis in Secondary Lymphedema through PDGF.

Lymphedema is a chronic and progressive condition that causes physical disfigurement and psychological trauma due to the accumulation of lymphatic fluid in the interstitial space. Once it develops, lymphedema is difficult to treat because it leads to the fibrosis of adipose tissue. However, the mechanism behind this remains unclear. The purpose of this study was to investigate the involvement of mast cells (MCs) in the adipose tissues of patients with lymphedema. We found that fibrosis spread through blood vessels in the adipose tissues of lymphedema patients, and the expression of the collagen I and III genes was significantly increased compared to that of those in normal adipose tissue. Immunostaining of vimentin and α-smooth muscle actin showed that fibroblasts were the main cellular components in severely fibrotic regions. Toluidine blue staining confirmed a significant increase in the number of MCs in the adipose tissues of lymphedema patients, and immunostaining of serial sections of adipose tissue showed a significant increase in the number of tryptase-positive cells in lymphedema tissues compared with those in normal adipose tissues. Linear regression analyses revealed significant positive correlations between tryptase and the expressions of the TNF-α, platelet-derived growth factor (PDGF)-A, and PDGFR-α genes. PDGF-A-positive staining was observed in both fibroblasts and granules of tryptase-positive MCs. These results suggest that MC-derived tryptase plays a role in the fibrosis of adipose tissue due to lymphedema directly or in cooperation with other mediators.

Giant Density of States Enhancement Driven by a Zero-Mode Landau Level in Semimetallic Black Phosphorus under Pressure.

Dirac fermion systems form a unique Landau level at the Fermi level-the so-called zero mode-whose observation itself will provide strong evidence of the presence of Dirac dispersions. Here, we report the study of semimetallic black phosphorus under pressure by ^{31}P-nuclear magnetic resonance measurements in a wide range of magnetic field up to 24.0 T. We have found a field-induced giant enhancement of 1/T_{1}T, where 1/T_{1} is the nuclear spin lattice relaxation rate: 1/T_{1}T at 24.0 T reaches more than 20 times larger than that at 2.0 T. The increase in 1/T_{1}T above 6.5 T is approximately proportional to the squared field, implying a linear relationship between the density of states and the field. We also found that, while 1/T_{1}T at a constant field is independent of temperature in the low-temperature region, it steeply increases with temperature above 100 K. All these phenomena are well explained by considering the effect of Landau quantization on three-dimensional Dirac fermions. The present study demonstrates that 1/T_{1} is an excellent quantity to probe the zero-mode Landau level and to identify the dimensionality of the Dirac fermion system.

Secondary Reconstruction of Late Deformities of the Orbitozygomaticomaxillary Complex using a Halo Device.

Reconstructing late deformities of the orbitozygomaticomaxillary complex after inadequate treatment of facial fractures requires zygomatic osteotomy to reposition the bony fragments to their anatomical position. However, confirming the position of the bone fragments can be challenging due to the loss of anatomic landmarks caused by bone remodeling, and swelling resulting from surgery, which might hinder locating the bone from the body surface. Here, the authors describe fixation of the halo of the Blue Device multi-vector distraction system to the patient's ear canal, with alignment of the position of the zygoma by measuring the distances between the halo and zygoma using several reference points. This technique allows for measurement not only from the body surface using a K-wire but also directly to the bone using a needle. The authors applied this technique in 2 cases of post-traumatic deformities after complex zygomatic fractures. Both cases achieved an almost symmetrical appearance of the infraorbital region.

Orbital Roof Decompression and Transposition of Orbital Contents for Treatment of Orbital Deviation Associated With Fibrous Dysplasia.

A 25-year-old male was admitted to our institute complaining of caudal deviation of orbit. Surgery was performed through a coronal incision, a subtarsal incision, and a lynch incision. The periosteum of the orbital roof was raised, and the supraorbital wall was shaved cephalad in reference to the nonaffected side. Then the periosteum was incised from the inferior margin of the orbit to the medial and lateral palpebral ligaments, and the periosteum of the orbital floor was raised until the inferior orbital fissure. After the circumferential intraorbital periosteal detachment, the orbital contents could be readily moved cephalad ward. The outer table of the calvarial bone was transplanted to the orbital floor, and the palpebral ligaments were fixed 5 mm cranially. In the 5-year follow-up, the patient's visual function was normal, and no recurrence of fibrous dysplasia was observed.

Application of augmented reality (AR) technology to locate the cutaneous perforator of anterolateral thigh perforator flap: A case report.

Multi-detector row computed tomography (MDCT) makes it possible to visualize the peripheral perforators of the anterolateral thigh (ALT) flap. However, to transfer the preoperative MDCT angiography data to the operative field requires effective techniques. In this report, we describe an application of augmented reality (AR) technology to harvest the anterolateral thigh flap. A 36-year-old female presented with a T2N2 squamous cell carcinoma of the lateral tongue. The patient underwent hemiglossectomy and microsurgical reconstruction using the left ALT flap. Three dimensional (3D) images the vascular image, vascular with muscles and vascular with outline of the thigh ware prepared. Then these images were exposed to an AR device. The location of the perforator was determined using the 3D vascular image on AR. The intraoperative location of the cutaneous perforator corresponded with the predicted location which was confirmed using the AR technique. A 6 × 15 cm left ALT flap was transferred to the defect. Microsurgical anastomosis was performed on the left superior thyroid artery and the internal jugular vein. There were no complications during the postoperative course. At the 6-month follow-up, the patient showed no evidence of flap and donor site complications. Our experience suggests that AR technology may effectively support the transfer of MDCT angiography images onto surgical sites.

Treatment of scarring alopecia from trauma and surgical procedures in young patients using follicular unit hair transplantation.

INTRODUCTION: Hair loss due to scarring as a consequence of surgical procedures and trauma can impact young patients socially and emotionally. Recently follicular unit extraction (FUE) hair transplantation has been applied to scar treatment. PATIENTS AND METHODS: This report included four patients with scarring alopecia. All patients were female with a mean age of 12.5 years. Previous operations that caused scarring were sebaceous nevus excision with direct closure (n = 2), an extensive burn scar treated using an expander (n = 1) and cauterization for a congenital pigmented nevus (n = 1). The average size of the affected area was 10.5 cm2 . The FUE transplantation procedure was performed under local anesthesia. The number of grafts was set at approximately 25-30 grafts/ cm2 of scar. An electronic punch with a diameter of 0.8 mm was used for graft harvesting, and a 0.6-mm electronic punch was used to make cylindrical holes on recipient site. The donor sites were shaved followed by graft harvesting in two cases. For the other two cases, harvesting was done without shaving. RESULTS: The number of transplanted grafts was 60 to 600 (mean 288), and surgical time was 38 to 220 minutes (mean 108). The average dose of lidocaine was 1.4 mg/kg. The average survival rate of the grafts was 85%. CONCLUSION: Our experience in these cases suggests that this technique may be a viable option for the treatment of certain causes of scarring alopecia in the pediatric age group.

Comparison of the Biomechanical Stiffness of Titanium and Sonic Weld RX Osteofixation Systems for Monoblock Zygomaticomaxillary Complex Fractures.

ABSTRACT: Resorbable osteosynthesis systems are widely used for the fixation of zygomaticomaxillary complex (ZMC) fractures instead of titanium systems, because they do not have postoperative hardware-related complications. However, the strength of conventional resorbable systems is inferior to that of titanium systems. Recently, ultrasound-aided resorbable osteosynthesis systems, which have higher fixation than conventional resorbable osteosynthesis systems, have become available.The purpose of this study was to compare the mechanical stiffness of the ultrasound-aided resorbable and titanium osteosynthesis systems in a cadaveric monoblock ZMC fracture model. Three human cadaveric monoblock ZMC fracture models (6 zygomas) were created. The fixation materials included the titanium (Level One Fixation; KLS Martin, Germany) and ultrasound-aided resorbable osteofixation systems (SonicWeld RX; KLS Martin). The fixation methods included the 3-point (zygomaticofrontal [ZF], zygomaticomaxillary buttress, and inferior orbital rim [Group I]) and the 2-point (ZF + inferior orbital rim [Group IIa] and ZF + zygomaticomaxillary buttress [Group IIb]) fixations. Each fixation model was mechanically tested with a load of up to 100 N, based on the previously reported postoperative masseter muscle strength, and the stiffness was calculated. Titanium was found to be stiffer than SonicWeld RX, though not significantly different. The fixation points in decreasing order of stiffness were Group I, Group IIa, and Group IIb, though the differences were not significant. In conclusion, the 2-point fixation, including the ZF fixation with SonicWeld RX, can be used as an alternative to the 3-point titanium fixation, which is considered to be stronger and stiffer.

Functional reconstruction of total upper eyelid defects with a composite radial forearm-palmaris longus tenocutaneous free flap: A report of two cases.

This report presents reconstruction of wide- and full-thickness upper eyelid defects with a composite radial forearm-splitting palmaris longus tendon flap, which maintains eyelid opening and closing functions and supporting tissue in a Meibomian gland carcinoma in the right upper eyelid (case 1) and Merkel cell carcinoma in the right upper eyelid (case 2). After tumor resection with excisional margins, the defects involved the muscle, tarsal, and mucosa, with defect sizes of 60 × 40 mm and 85 × 40 mm, respectively. A radial forearm flap with the palmaris longus tendon was transferred. The tendon was split into two strips: the upper strip was fixed to the frontal muscles for the opening function and the lower strip to the medial palpebral ligament and orbicularis oculi muscle to maintain the closing function. Flap vessels were anastomosed to the superficial temporal artery and vein through the subdermal tunnel. Postoperative courses were uneventful. At the 5-year (case 1) and 4-year (case 2) follow-up periods, there were no tumor recurrence and keratalgia, and the eyelid opening and closing functions were maintained. This approach may contribute to achievement of not only the opening function but also the closing function of the reconstructed eyelid.

Microsurgical mandibular reconstruction using a resin surgical guide combined with a metal reconstructive plate.

INTRODUCTION: In mandibular reconstruction, repositioning the mandibular position is still challenging and time consuming. We invented a new re-positioning technique using a resin plate combined with a reconstructive plate in reconstructing the mandible with an osteocutaneous free flap. The purpose of this report is to introduce this technique and evaluate the accuracy of mandibular reconstruction using free flaps. We hypothesized that this technique is precise and can reduce intraoperative plate bending at a low cost and short preparation period. METHODS: Mandibular reconstruction was successfully performed in a total of 10 cases without any complications. In this technique, a pre-bent reconstructive plate was prepared in accordance with a three-dimensional model, and then coated with resin. Intraoperatively, the mandibles were secured by fitting these plates snugly and fixing them using a reconstructive plate. Then the resin was removed and free osteocutaneous free flaps were transfer to the defect. Ten patients with a mean age of 68.2 who underwent mandibular resection for aggressive benign (n = 1) or malignant disease (n = 9) were reconstructed using this technique. Seven cases were reconstructed using fibular osteocutaneous free flaps, while scapular osteocutaneous free flaps were used in the remaining cases. The resections entailed: unilateral symphysis and lateral body in four cases, angle to ipsilateral angle in two, ramus to symphysis in two, and lateral body plus angle to symphysis in one case. The deviation of the mandible was evaluated by measuring the preoperative versus postoperative differences in the distances between six bilateral landmarks. RESULTS: There were no complications and flap failure in any of the 10 cases. No further intraoperative plate bending was required. One case underwent additional mucosal resection due to recurrence of cancer. Three cases were referred to postoperative chemoradiotherapy. Two patients expired during follow-up due to recurrence of cancer. Six cases were put back on a normal diet. The other cases who lacked opposing teeth had to remain on a soft diet. The mean follow-up period was 46.2 months. The average of the absolute deviation values was 1.45 mm. This value was 0.94 mm in six cases with mandibular body defects and 2.26 mm in four cases with mandibular defects involving the ramus. CONCLUSIONS: The present novel technique is simple, quick to prepare, and accurate. This technique can be a viable option for microsurgical mandibular reconstruction.

Wider Suturectomy Before Posterior Distraction for Craniosynostosis.

The aim of the surgery for craniosynostosis is to release increased intracranial pressure and to normalize cranial shape. The procedure has developed so far in Japan, from a simple strip craniectomy before 1960s through a total calvarial remodeling after 1970s and later methods of 1990s, such as distraction and its modifications applying to the posterior cranium. Since a distracter needs certain hardness and thickness of the bone, the surgery has to be stood by until 5 to 6 months of age. Modified Jimenez procedure, as a latest option, were applied for very early years of 10 patients with several types of craniosynostosis, in our team in the past 3 years. The experience was small with short follow-up; the results are all good in those volume change and shape. The procedure proved to be another alternative especially prior to posterior distraction of syndromic patients in terms of positive and expedited control in an earlier surgical management.

Telementoring Demonstration in Craniofacial Surgery With HoloLens, Skype, and Three-Layer Facial Models.

BACKGROUND: Telementoring is the technology for providing surgical instruction from a remote place via a network. To demonstrate the use of telementoring in craniofacial surgery, Skype and a mixed reality device HoloLens were adopted, and 3-layer facial models had been developed. METHODS: A resident in hospital A used the model surgery under remote guidance by a mentor surgeon in hospital B 4 times on different dates. The straight-line between hospitals A and B is 250 km. The mentor gave the resident guidance via Skype and HoloLens, communicating by voice, and video of the surgical field, and providing reference data. RESULTS: There was no delay in voice communication and a delay of <0.5 seconds in the video. The resident was able to confirm the main landmarks of the surgical field and to grasp the situation without problems. The mentor could send appropriate instructions by voice, could point out a specific part by telestration function, and could draw lines on the 2-dimentional images pasted on the operator's field of vision. DISCUSSION: With the use of HoloLens, Skype, and the 3-layer models, it was possible to demonstrate telementoring. The risk of personal information leakage due to data interception seems to be very low because its data communication is encrypted with advanced encryption standard. CONCLUSION: This telementoring system has various advantages and many improvable aspects in the field of craniofacial surgery.

W9 peptide enhanced osteogenic differentiation of human adipose-derived stem cells.

W9 is a peptide that abrogates osteoclast differentiation via blockade of nuclear factor-κB ligand (RANKL)-RANK signaling, which activates bone formation. However, W9 stimulated osteogenesis in osteoblasts and mesenchymal stem cells. The present study demonstrated that the W9 peptide promoted osteogenic differentiation of human adipose-derived stem cells (hAdSCs) even under non-osteogenic differentiation culture conditions. W9-treated hAdSCs exhibited several osteocalcin-expressing cells and great mineralization compared to the BMP2-treated hAdSCs, which suggests that the W9 peptide had potent osteogenic potential in hAdSCs. W9 treatment also markedly enhanced the phosphorylation of p38, JNK, Erk1/2, and Akt, and BMP2 treatment only enhanced the phosphorylation of p38 and Erk1/2 in hAdSCs. hAdSCs did not express the RANKL gene, but W9 treatment upregulated Runx2, Collagen type 1A1 and TGF receptor genes and increased Akt phosphorylation. These results suggest that the W9-induced potent osteogenic induction was attributed to activation of TGF and the PI3 kinase/Akt signaling pathway in hAdSCs.

Application of free serratus anterior fascial flap for reconstruction of ear deformity due to hemifacial microsomia: A report of two cases.

Reconstructing congenital auricular defects due to hemifacial microsomia (HFM) is often required to deal with low hairline and defects of the temporal fascia/muscular systems. In this report, we present two cases of HFM patients (16-year-old and 20-year-old) with positional anomaly of the remnant lobule and 95% low hairline, who were treated with serratus anterior fascial flap (SFF) at the second stage of auricular construction. At the first stage, 3D costal cartilage framework was placed following the removal of hair-bearing skin, and was resurfaced with the pericranial flap. At the second stage, ear elevation was performed with cartilage block grafting, then the free SFF was used to construct cephaloauricular sulcus because of local fascial defect. The pedicles of SFF, subscapular vessels were anastomosed to the cervical vessels. No complications developed during the follow-up period of 4 years in both cases and projections of the constructed ears were satisfactorily maintained. The free SFF is naturally thin and flexible with sufficient circulation and it may be an alternative to temporo-parietal fascia flap in complicated microtia construction in HFM. © 2016 Wiley Periodicals, Inc. Microsurgery 37:436-441, 2017.

Reconstruction of the dynamic velopharyngeal function by combined radial forearm-palmaris longus tenocutaneous free flap, and superiorly based pharyngeal flap in postoncologic total palatal defect.

We attempted to reconstruct dynamic palatal function using a radial forearm-palmaris longus tenocutaneous free flap in conjunction with a pharyngeal flap for a postoncologic total-palate defect in a 67-year-old male patient. This reconstruction involved 3 important tasks, namely, separating the oral and nasal cavities, preserving the velopharyngeal space to avoid sleep apnea, and maintaining velopharyngeal closure to avoid nasal regurgitation during swallowing. In our technique, the radial forearm flap separates the oral and nasal cavities with an open rhinopharyngeal space, and a superiorly based pharyngeal flap, which is sutured to the posterior end of the forearm flap, limits the rhinopharyngeal space, and forms the bilateral velopharyngeal port. Furthermore, the palmaris longus tendon, which is attached to the forearm flap, is secured to the superior constrictor muscle to create a horizontal muscle sling. Contraction of the superior constrictor muscle leads to shrinkage of the sling, resulting in velopharyngeal closure. Swallowing therapy was started 4 weeks after the surgery. The patient could resume oral intake without any difficulties 6 months after the surgery. Speech intelligibility changed from severe to minimal hypernasality.

Constitutive plasmacytoid dendritic cell migration to the splenic white pulp is cooperatively regulated by CCR7- and CXCR4-mediated signaling.

Although the spleen plays an important role in host defense against infection, the mechanism underlying the migration of the innate immune cells, plasmacytoid dendritic cells (pDCs), into the spleen remains ill defined. In this article, we report that pDCs constitutively migrate into the splenic white pulp (WP) in a manner dependent on the chemokine receptors CCR7 and CXCR4. In CCR7-deficient mice and CCR7 ligand-deficient mice, compared with wild-type (WT) mice, substantially fewer pDCs were found in the periarteriolar lymphoid sheath of the splenic WP under steady-state conditions. In addition, the migration of adoptively transferred CCR7-deficient pDCs into the WP was significantly worse than that of WT pDCs, supporting the idea that pDC trafficking to the splenic WP requires CCR7 signaling. WT pDCs responded to a CCR7 ligand with modest chemotaxis and ICAM-1 binding in vitro, and priming with the CCR7 ligand enabled the pDCs to migrate efficiently toward low concentrations of CXCL12 in a CXCR4-dependent manner, raising the possibility that CCR7 signaling enhances CXCR4-mediated pDC migration. In agreement with this hypothesis, CCL21 and CXCL12 were colocalized on fibroblastic reticular cells in the T cell zone and in the marginal zone bridging channels, through which pDCs appeared to enter the WP. Furthermore, functional blockage of CCR7 and CXCR4 abrogated pDC trafficking into the WP. Collectively, these results strongly suggest that pDCs employ both CCR7 and CXCR4 as critical chemokine receptors to migrate into the WP under steady-state conditions.

Novel Finding of an Excess Bone in Postaxial Polydactyly of the Foot.

Background: Postaxial polydactyly is a common congenital foot anomaly. However, the severity of the anomaly varies from simple cases with only soft tissue duplication to complex cases with bone and joint disorders. In our clinical practice, we found a new morphological anomaly of postaxial polydactyly. We encountered several cases of postaxial polydactyly with bone fragments located between the fourth and fifth toes. The bone fragments were independent of the joint cavity. The mechanisms underlying its development remain unknown because it is a novel disorder. In the present study, we investigated the characteristics of the excess bone to formulate an embryological hypothesis. Methods: We examined the frequency and trends in the occurrence of excess bone using data from photographs and radiographs of these cases. An example of a disorder similar to excess bone is mosaic-like alignment, as reported by Iba et al. We also compared the characteristics of the mosaic-like alignment with those of the excess bone. Based on these data and existing embryological knowledge, we hypothesized the origin of the excess bone. Results: Excess bone and mosaic-like alignments showed different characteristics. Therefore, both were considered completely different disorders. We hypothesized that excess bone was caused by damage to the interdigital ectoderm immediately before interdigital programmed cell death. Conclusions: We encountered a new form of postaxial polydactyly. This can be a factor influencing the treatment strategy because it can affect alignment and stability.

A Case of Bilateral Lambdoid and Sagittal Synostosis Diagnosed with Skull Fracture after Vacuum-assisted Delivery: A Case Report and Literature Review.

Craniosynostosis (CS) can develop in the fetal period, but it is difficult to diagnose prenatally. In this case, a 3-month-old female baby developed extensive subgaleal hematoma and severe anemia after vacuum-assisted delivery. Her computed tomography showed bilateral lambdoid and sagittal synostosis (BLSS) with a depressed fracture of the right parietal bone. She was referred to our hospital for treatment of the CS. At 4 months of age, she underwent bilateral lambda and sagittal suturectomy and foramen magnum decompression. CS may result in trauma at delivery, because CS disturbs fetal head molding during delivery and disrupts passage through the birth canal. In particular, the risk of severe peripartum trauma is thought to increase in cases of CS with multiple suture fusions, such as those observed in BLSS, due to the strong inhibition of this process of passage through the birth canal. Therefore, if the delivery is abnormally prolonged or if the infant has a massive subgaleal hematoma, it is important to perform evaluations for CS after birth.

Treatment of Refractory Ascites with Lymphaticovenous Anastomosis Considering Lymphatic Territories.

Lymphatic ascites is an infrequent complication observed in patients who have undergone lymphadenectomy as part of their surgical treatment for gynecological cancer. Previous research has suggested that intranodal lymphangiography can effectively manage lymphatic leakage. However, its efficacy diminishes for ascites with substantial fluid accumulation. This case report presents a patient who underwent lymphaticovenous anastomosis (LVA) for ascites that was unresponsive to lymphangiography and sclerotherapy. A 70-year-old woman required weekly ascites punctures after surgical treatment of ovarian cancer. Lymphoscintigraphy revealed lymphatic leakage originating from the right pelvic lymphatic vessel. Intranodal lymphangiography was performed from the inferior lateral inguinal region, followed by embolization with 33% NBCA. Despite these measures, recurrence of ascites and lower limb lymphedema were observed. LVA was conducted at 149 days after the primary operation. Before the LVA, indocyanine green was injected into the lateral and medial ankles, first and fourth toe web spaces, and lower abdomen. The indocyanine green lymphography revealed several linear patterns extending from the dorsum of the foot and the lower abdomen to the inguinal lymph node. Among these, the lymphatic vessels leading to the inferior lateral inguinal lymph node were chosen for the LVA. Eight anastomoses were executed at the right thigh, right lower leg, and right lower abdomen. The patient was discharged at 1 day postoperatively. A computed tomography examination conducted at 20 days post-LVA revealed no accumulation of ascites. To improve the success rate of LVA for ascites, a treatment strategy based on lymphatic territories is required.

Bronchogenic cysts in rare sites (retroperitoneum, skin, spinal cord and pericardial cavity): A case series and characterization of epithelial phenotypes.

Bronchogenic cysts are congenital malformations of the bronchial tree, detected as a cystic and/or mass lesion in the thoracic cavity. Although it occurs in distant locations, such as skin and retroperitoneum, to the best of our knowledge, little is known about the components and phenotypes of the epithelium that line a bronchogenic cyst in rare sites. The present study reviewed 34 bronchogenic cysts that were surgically resected at Osaka Medical and Pharmaceutical University Hospital (Osaka, Japan) from January 1998 to December 2020. Bronchogenic cysts in rare sites were detected and diagnosis was confirmed based on the presence of pseudostratified, ciliated and/or columnar epithelium together with at least one of the following: Cartilage, smooth muscle or seromucous glands. The phenotypes of epithelium lining the cyst were characterized using immunohistochemical analysis. A total of six bronchogenic cysts in rare sites (two cases each in the retroperitoneum and skin and one case each in the cervical spinal cord and pericardial cavity) met the criteria for confirmation of the diagnoses. The epithelium lining the cyst stained positive for cytokeratin CK7 and thyroid transcription factor 1 (a marker expressed in thyroid follicles and bronchial epithelium) and negative for CK20, indicating that the phenotypes were similar to those of the respiratory epithelium. The present study demonstrated that a bronchogenic cyst can occur in rare sites, such as the retroperitoneum, skin, spinal cord and pericardial cavity, suggesting that it should be considered as a differential diagnosis before surgical approach to implement relevant management modalities such as follow-up, simple or radical resection.

Pretaporter, a Drosophila protein serving as a ligand for Draper in the phagocytosis of apoptotic cells.

Phagocytic removal of cells undergoing apoptosis is necessary for animal development and tissue homeostasis. Draper, a homologue of the Caenorhabditis elegans phagocytosis receptor CED-1, is responsible for the phagocytosis of apoptotic cells in Drosophila, but its ligand presumably present on apoptotic cells remains unknown. An endoplasmic reticulum protein that binds to the extracellular region of Draper was isolated. Loss of this protein, which we name Pretaporter, led to a reduced level of apoptotic cell clearance in embryos, and the overexpression of pretaporter in the mutant flies rescued this defect. Results from genetic analyses suggested that Pretaporter functionally interacts with Draper and the corresponding signal mediators. Pretaporter was exposed at the cell surface after the induction of apoptosis, and cells artificially expressing Pretaporter at their surface became susceptible to Draper-mediated phagocytosis. Finally, the incubation with Pretaporter augmented the tyrosine-phosphorylation of Draper in phagocytic cells. These results collectively suggest that Pretaporter relocates from the endoplasmic reticulum to the cell surface during apoptosis to serve as a ligand for Draper in the phagocytosis of apoptotic cells.