Biological impact of polyacetal particles on loosening of isoelastic stems

The aim of our study was to identify biological factors responsible for premature loosening of polyacetal hip stems. The results of histological analyses of the tissue around 11 total hip prostheses with loosened polyacetal femoral stems were compared to those obtained in a group of 11 total hip prostheses with loosened metal (CoCr) femoral components. A higher number of polymer wear particles surrounded by giant cells, more bone chips, and a more extensive necrosis were found around loosened polyacetal stems. Histomorphological characteristics of polyacetal wear particles containing BaSO(4) granules in the tissue around loosened polyacetal stems were described. Radiological evaluation of the wear of polyethylene cups suggested that elastic modulus of the stem had no influence on the wear of polyethylene cups. This study indicates that polyacetal wear particles have a great biological potential accelerating the process of loosening.     

Serglycin induces osteoclastogenesis and promotes tumor growth in giant cell tumor of bone

Giant cell tumor of bone (GCTB) is an aggressive osteolytic bone tumor characterized by the within-tumor presence of osteoclast-like multinucleated giant cells (MGCs), which are induced by the neoplastic stromal cells and lead to extensive bone destruction. However, the underlying mechanism of the pathological process of osteoclastogenesis in GCTB is poorly understood. Here we show that the proteoglycan Serglycin (SRGN) secreted by neoplastic stromal cells plays a crucial role in the formation of MGCs and tumorigenesis in GCTB. Upregulated SRGN expression and secretion are observed in GCTB tumor cells and patients. Stromal-derived SRGN promotes osteoclast differentiation from monocytes. SRGN knockdown in stromal cells inhibits tumor growth and bone destruction in a patient-derived orthotopic xenograft model of mice. Mechanistically SRGN interacts with CD44 on the cell surface of monocytes and thus activates focal adhesion kinase (FAK), leading to osteoclast differentiation. Importantly, blocking CD44 with a neutralizing antibody reduces the number of MGCs and suppresses tumorigenesis in vivo. Overall, our data reveal a mechanism of MGC induction in GCTB and support CD44-targeting approaches for GCTB treatment.Subject terms: Bone cancer, Cancer microenvironment, Mechanisms of disease     

Multinucleated giant cells in fine needle aspirates. Can they help differentiate papillary thyroid cancer from benign nodular goiter?

OBJECTIVE: To determine whether multinucleated giant cells (MGCs) in fine needle aspirates can help differentiate papillary thyroid carcinoma (PTC) from benign nodular goiter (BNG). STUDY DESIGN: Specimens from 100 cases of PTC and 100 cases of BNG with surgical and pathologic proof were randomly retrieved. The morphologic characteristics and frequency distribution of the maximal size and number of MGC nuclei were analyzed. A retrospective review of medical records was also undertaken. RESULTS: MGCs were twice as frequent (40%) in PTC than in BNG (26%) (odds ratio = 1.90). Most MGCs in BNG tended to be smaller and ovoid, with foamy cytoplasm, and had fewer nuclei. No MGC in BNG was > 116 microns in diameter or had > 27 nuclei. In contrast, MGCs in PTC were more diverse in size, shape, cytoplasm and number of nuclei. No significant association was found between the presence or nature of MGCs and disease extent in PTC. CONCLUSION: The presence of large MGCs with dense cytoplasm in a thyroid nodule without clinical evidence of thyroiditis should prompt careful exclusion of associated PTC.     

Pulmonary Multinucleate Giant Cells in Dermatosis Vegetans in Swine: Light microscopic and immunohistochemical investigations

Five pigs with dermatosis vegetans (DV), aged 1–28 days, were examined with the purpose of describing the pulmonary changes and to characterize the pulmonary multinucleate giant cells (MGC) and their possible cytogenesis. No pulmonary changes were present at birth. From 7 days of age, lung changes were characterized by proliferation of alveolar epithelial cells and formation of MGCs. Immunostaining for cytokeratin by a peroxydase–streptavidin method gave a positive reaction in MGCs, bronchial, bronchiolar and alveolar epithelium. MGCs seemed to be formed in the course of alveolar epithelial proliferations, and type-II pneumocytes were proposed as possible precursors.     

Bacterial lipopolysaccharide induces osteoclast formation in RAW 264.7 macrophage cells

Lipopolysaccharide (LPS) is a potent bone resorbing factor. The effect of LPS on osteoclast formation was examined by using murine RAW 264.7 macrophage cells. LPS-induced the formation of multinucleated giant cells (MGC) in RAW 264.7 cells 3 days after the exposure. MGCs were positive for tartrate-resistant acid phosphatase (TRAP) activity. Further, MGC formed resorption pits on calcium-phosphate thin film that is a substrate for osteoclasts. Therefore, LPS was suggested to induce osteoclast formation in RAW 264.7 cells. LPS-induced osteoclast formation was abolished by anti-tumor necrosis factor (TNF)-alpha antibody, but not antibodies to macrophage-colony stimulating factor (M-CSF) and receptor activator of nuclear factor (NF)-kappaB ligand (RANKL). TNF-alpha might play a critical role in LPS-induced osteoclast formation in RAW 264.7 cells. Inhibitors of NF-kappaB and stress activated protein kinase (SAPK/JNK) prevented the LPS-induced osteoclast formation. The detailed mechanism of LPS-induced osteoclast formation is discussed.     

HIV-1 (p24)-positive multinucleated giant cells in HIV-associated lymphoepithelial lesion of the parotid gland. A report of two cases

BACKGROUND: Cystic benign lymphoepithelial lesion (CBLL) is a well-recognized parotid disorder the diagnosis of which can be made on the basis of clinical findings, human immunodeficiency virus (HIV) testing, image studies and fine needle aspiration (FNA). Most aspirations are cystic, and the lesion can be recognized if the triad of foamy macrophages, lymphoid and epithelial (squamous) cells is observed. CASES: The authors recently observed FNA cytologic features of two HIV-associated cases that exhibited numerous multinucleated giant cells (MGCs) but failed to show the epithelial component. A subsequent surgical resection was performed in one patient. Similarly to what has been described for nasopharyngeal (adenoid and tonsil) lymphoid tissue of HIV-positive patients, intense immunoexpression of S-100 and p24 (HIV-1) protein was present in MGC. CONCLUSION: The diagnosis of HIV-associated CBLL should always be considered if a parotid cystic lesion presents with numerous MGCs. Immunocytochemical detection of p24 (HIV-1) protein in MGC becomes a very useful diagnostic aid and extends to parotid CBLL many of those pathogenic features of HIV-1 infection already noted in other HIV-1-infected, lymphoid oropharyngeal lesions.     

IL-4, but not vitamin D(3), induces monoblastic cell line UG3 to differentiate into multinucleated giant cells on osteoclast lineage

The formation of multinucleated giant cells (MGCs) from monocytes/macrophages is controlled by various cytokines, the roles of which are not fully understood. Both interleukin (IL)-4 and 1alpha,25(OH)(2) vitamin D(3) (D(3)) are known to induce MGC formation from monocytes/macrophages. D(3) is also known as a stimulator of osteoclast formation in the presence of stroma cells, and IL-4 as an inhibitor. Previously, we showed that IL-4-induced MGCs from monocytes/macrophages expressed tartrate resistant acid phosphatase (TRAP) activity and hydroxyapatite-resorptive activity in the presence of M-CSF without stroma cells. In this study, we examined the effects of D(3) and/or IL-4 on MGC formation and the characteristics of these MGCs using a monoblastic cell line (UG3), to elucidate the involvement of these factors in osteoclast development without stroma cells. D(3)-induced MGCs showed none of the markers of osteoclasts, such as TRAP activity, calcitonin receptor (cal-R) expression, hydroxyapatite-resorptive activity, and bone-resorptive activity. A low concentration of D(3) synergistically stimulated IL-4-induced TRAP-positive MGC formation, whereas a high concentration of D(3) inhibited it. When IL-4 was added on day 7 of the 2-week culture with D(3), TRAP positivity reached maximum. On the other hand, delayed addition of D(3) on day 7 of culture did not increase the TRAP positivity. Although the fusion rate increased during the first week of the 2-week culture in the presence of D(3), it increased further in the second week following the addition of IL-4 on day 7. Furthermore, IL-4-induced, or IL-4- and D(3)-induced MGCs differentiated into functional osteoclasts with bone-resorptive activity following coculture with osteoblastic cells, whereas D(3)-induced MGCs did not acquire bone-resorptive activity even after coculture with osteoblastic cells in the presence of D(3). These findings suggest that IL-4 initiates osteoclast development of UG3 cells, although stroma cells were necessary for development of functional osteoclasts. On the other hand, D(3) had only a "supportive" effect on this differentiation. IL-4 and direct contact with stroma cells may regulate different stages in the multistep process of osteoclastogenesis of UG3 cells.     

Fungicidal activity of human monocyte-derived multinucleated giant cells induced in vitro by Paracoccidioides brasiliensis antigen

Multinucleated giant cells (MGC) are characteristic cells in granulomatous disorders such as paracoccidioidomycosis (PCM) and also are formed in vitro from peripheral blood mononuclear cells by several stimuli. In this study, the authors investigated in vitro formation of MGC derived from monocytes of healthy individuals, stimulated with Paracoccidioides brasiliensis antigen (PbAg), compared with other stimuli such as IFN-gamma and supernatant of Con-A-stimulated peripheral blood mononuclear cells (CM-ConA). Besides, the fungicidal activity of monocytes and monocyte-derived MGC challenged with P. brasiliensis were compared, at a ratio of one fungus per 50 monocytes. Results demonstrated that PbAg, IFN-gamma, and CM-ConA stimuli were able to induce MGC generation, with fusion indices significantly higher than control cultures. Striking results were observed when MGC induced by PbAg and IFN-gamma presented higher fungicidal activity than monocytes, submitted to the same stimuli, showing a better capacity of these cells to kill P. brasiliensis. In summary, the results suggest that PbAg is able to induce MGC generation, and these cells presented higher fungicidal activity against P. brasiliensis than monocytes.     

Tumor necrosis factor-α can induce Langhans-type multinucleated giant cell formation derived from myeloid dendritic cells

The formation of the rich cellular features of MGCs, where the nuclei are arranged circularly at the periphery of the cell (morphologically epithelioid; Langhans-type), is assumed to be associated with any granulomatous disease. The mechanism by which TNF controls the formation of human MGCs in vitro was investigated, focusing on the effect of the TNF-neutralizing antibody. Peripheral blood monocytes were isolated with mAb-coated immunologic magnetic beads and cultured for 10 days in the presence of 20 ng/mL GM-CSF and 10 ng/mL IL-4. These cells were further incubated in the presence of TNF-α with/without its blockade antibodies for 14 days. Myeloid DCs can be generated from peripheral blood monocytes, and both IL-4 and GM-CSF can provide sufficient stimulus for their differentiation. The formation of MGC can be induced in the presence of TNF-α. This reaction was prohibited by the presence of the TNF-neutralizing antibody but not by the presence of anti-TNF receptor II antibody. The activation of Rho and focal adhesion kinases induced by TNF-α stimulation might be linked to cell assembling and the formation of Langhans-type MGCs. MGCs can produce only small amounts of superoxide anions compared to isolated macrophages such as myeloid DCs.     

Transformation of blood monocytes to multinucleated giant cells in vitro: are there any differences between malignant and nonmalignant states?

Blood monocytes (BMs) from 139 subjects (70 malignant melanoma patients, 31 breast cancer patients, 38 healthy controls) were cultured for at least 7 days. The formation of multinucleated giant cells (MGCs), which was checked during the whole time of culture, was observed in all cases. By the seventh day MGCs represented 25-50% and during the second and third month more than 90% of all cells. Lymphokines and/or concanavalin A stimulation (16-34 cases respectively) of BMs was performed as well. This stimulation greatly accelerated MGC formation. There were no differences either in spontaneous or in stimulated fusion between the different groups compared.     

Characterization of mode II-wear particles and cytokine response in a human macrophage-like cell culture.

Informations about wear particles in metallosis (mode II wear) and their effects in vitro and in vivo are limited. The aim of this study was to characterize wear particles obtained intraoperatively and to analyse their effects on cytokine response in an established human macrophage-like cell culture model. METHOD: Wear particles were obtained intraoperatively from four patients with metallosis resulting from CrCoMo/PE/TiAIV-implants (mode II wear) (3 knee, 1 hip prosthesis). After purification, particles were characterized regarding to their composition and size (particle size analyser, electron microscopy, edx-analysis, histological slices). The effects of particles on the release of cytokines (PDGF, IL-1beta, IL-8, TNF alpha) were determined in an established human macrophage-like cell culture system by ELISA-assays. RESULTS: The metal wear particles consisted of TiAIV with a mean size of 0.1 +/- 0.15 microm, independent of the prosthesis location. CrCoMo particles could not be detected. In the cell culture model 1456 x 10(8) particles per 1 x 10(6) macrophages released maximum amounts of TNFalpha (8-fold) and IL-8 and IL-1beta (5-fold) while the survival rate of the cells was more than 90 percent. A particle-dependent increase of PDGF-levels could not be detected. CONCLUSION: As already shown for mode I wear particles (contact between primary bearing surfaces), also mode II wear particles cause release of bone resorbing cytokines in a macrophage-like cell culture model. Because their local and systemic effects in vivo are still not completely understood, we recommend a complete removal of wear particles in cases of metallosis to avoid possible immunological reactions of the body as well as periprosthetic osteolysis.     

Fine needle aspiration cytology of mammary carcinoma with choriocarcinomatous features: a report of 2 cases

BACKGROUND: Neoplasms of the breast containing multinucleated giant cells (MGCs) include both benign and malignant entities, such as benign soft tissue giant cell tumors, atypical fibrous histiocytoma, sarcomas, metaplastic carcinomas and the uncommon carcinomas containing osteoclast-like giant cells (OGC). Breast carcinoma with choriocarcinomatous features (BCCF) is a distinct variant of breast cancer. CASES: We report the cytologic features, pathologic findings and immunohistochemical profile in 2 cases of this unusual variant of breast carcinoma. Two women aged 53 and 50 years women presented with a history of left and right breast lump but no local lymphadenopathy, respectively. Fine needle aspiration cytology (FNAC) of both cases revealed abundant MGC with highly pleomorphic tumor cells in the hemorrhagic necrotic background. Both of the cases were histopathologically diagnosed as BCCF. CONCLUSION: Choriocarcinomatous differentiation with multinucleated syncytiotrophoblast-like giant cells is extremely rare in breast tumors. Although rare, FNAC of breast cancer with pleomorphic MGC requires careful search for differential diagnosis; breast carcinoma with giant cell features (choriocarcinomatous features, OGC features) must be differentiated from metastatic tumors and other breast lesions containing giant cells.     

Granulocyte macrophage colony-stimulating factor enhances the modulatory effect of cytokines on monocyte-derived multinucleated giant cell formation and fungicidal activity against Paracoccidioides brasiliensis

Multinucleated giant cells (MGC) are cells present in characteristic granulomatous inflammation induced by intracellular infectious agents or foreign materials. The present study evaluated the modulatory effect of granulocyte macrophage colony-stimulating factor (GM-CSF) in association with other cytokines such as interferon-gamma (IFN-γ), tumour necrosis factor-alpha, interleukin (IL)-10 or transforming growth factor beta (TGF-β1) on the formation of MGC from human peripheral blood monocytes stimulated with Paracoccidioides brasiliensis antigen (PbAg). The generation of MGC was determined by fusion index (FI) and the fungicidal activity of these cells was evaluated after 4 h of MGC co-cultured with viable yeast cells of P. brasiliensis strain 18 (Pb18). The results showed that monocytes incubated with PbAg and GM-CSF plus IFN-γ had a significantly higher FI than in all the other cultures, while the addition of IL-10 or TGF-β1 had a suppressive effect on MGC generation. Monocytes incubated with both pro and anti-inflammatory cytokines had a higher induction of foreign body-type MGC rather than Langhans-type MGC. MGC stimulated with PbAg and GM-CSF in association with the other cytokines had increased fungicidal activity and the presence of GM-CSF also partially inhibited the suppressive effects of IL-10 and TGF-β1. Together, these results suggest that GM-CSF is a positive modulator of PbAg-stimulated MGC generation and on the fungicidal activity against Pb18.     

The transport of wear particles in the prosthetic hip joint: a computational fluid dynamics investigation

The joint fluid mechanics and transport of wear particles in the prosthetic hip joint were analyzed for subluxation and flexion motion using computational fluid dynamics (CFD). The entire joint space including a moving capsule boundary was considered. It was found that particles suspended in the joint space are drawn into the joint gap between prosthesis cup and head during subluxation, which was also documented by Lundberg et al. (2007; Journal of Biomechanics 40, 1676-1685), however, wear particles remain in the joint gap. Wear particles leave the joint gap during flexion and can finally migrate to the proximal boundaries including the acetabular bone, where the particle deposition can cause osteolysis according to the established literature. Thus, the present study supports the theory of polyethylene wear particle induced osteolysis of the acetabular bone as a major factor in the loosening of hip prosthesis cups.     

Identification of wear particles of joint prostheses in tissues using laser microprobe mass analysis (LAMMA)]

The definite identification of wear particles from joint prostheses is of great importance for the development of joint replacement, as the type and quantity of different wear particles gives information on the wear resistance of implant materials. From the types of prostheses nowadays in use polyethylene wear of the sockets, bone cement wear, metallic and ceramic wear can be generated. Whereas polyethylene wear can be easily identified by its bright luminescence in polarized light and its characteristic configuration, the distinction of the small granular wear particles of the bone cement, metal and ceramic by light microscope is difficult. The laser microprobe mass analysis (LAMMA) is a method, which allows the analysis of single light microscopically detectable wear particles in tissues. Not only contrast medium particles of the bone cements (zirconium oxide or barium sulfate) but also metallic and aluminum oxide particles could be definitely identified within the pseudocapsules as well as in regional lymph nodes by LAMMA-analysis, whereby the bone cement wear predominated. In addition, the distinction between organic substances (as blood degradation products), which may appear similar to wear particles in configuration and colour, and the foreign material is also possible with this method.     

肝细胞生长因子对骨髓内皮祖细胞的动员作用

目的: 分析肝细胞生长因子(HGF)能否动员骨髓内皮祖细胞,以及动员的内皮祖细胞能否参与创伤修复时的血管新生和内皮修复.方法: 将腺病毒HGF载体(adenovirus vector encoding HGF gene, Ad-HGF)经尾静脉注射到Balb/c小鼠体内,用ELISA方法检测血浆HGF水平的变化;用流式细胞术检测外周血CD34 细胞含量变化;对外周血单个核细胞进行分离、培养,并对生长的细胞克隆进行内皮细胞表面标志Tie-2、vW因子的免疫组化检测.建立雌性小鼠CCl4肝损伤模型,静脉移植HGF处理后雄性小鼠外周血单个核细胞到其体内,4 W后利用原位杂交技术检测新生肝组织中是否存在雄性细胞.结果: 注射Ad-HGF能明显提高小鼠血浆的HGF水平,并使外周血中以CD34、Tie-2和vW因子等为标志的内皮祖细胞的数量显著增多.这些细胞参与肝损伤修复时的血管新生.结论: HGF对骨髓内皮祖细胞具有明显的动员作用.