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1.
Immunopharmacol Immunotoxicol ; 42(6): 614-624, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33070657

RESUMO

CONTEXT: Effects of liposomal particles on immune function have not been adequately investigated. Earlier reports indicate that intravenous injection of rats with pegylated liposomes comprising chemically defined specific lipids produces myeloid derived suppressor-cell (MDSC)-like cells in the spleen. OBJECTIVES: After liposome injection, we sought a cell surface marker expressed specifically on splenic macrophages. Then we assessed the immunosuppressive activity of macrophages positive for the marker. Furthermore, we investigated whether immunosuppression induction is an immunopharmacological action specific to this pegylated liposome, or not. MATERIALS AND METHODS: After using a microarray system to screen genes enhanced by this liposome, we evaluated cell surface expression of gene products using flow cytometry. Liposomes of several kinds, each comprising one type of phospholipid, were prepared and evaluated for their ability to induce T-cell suppression. RESULTS: Microarray analysis indicated enhanced B7-H3 expression. Flow cytometry revealed that the B7-H3 molecule was expressed on splenic macrophages after liposome injection. B7-H3+ macrophages were positive for iNOS. Removing B7-H3+ cells restored T-cell proliferation. Similarly to this liposome, various liposomes with different long chain fatty acids induced T-cell suppression when accumulated in the spleen. CONCLUSIONS: Immunosuppressive cells induced by this pegylated liposome closely resemble MDSCs, especially B7-H3+ MDSCs. Immunosuppression induction is not a phenomenon specific to this liposome. Accumulation of long chain fatty acid in macrophages by internalization of liposomal nanoparticles might be related to macrophage acquisition of immunosuppressive activity in vivo.


Assuntos
Antígenos B7/metabolismo , Ácidos Graxos/administração & dosagem , Tolerância Imunológica/efeitos dos fármacos , Lipídeos/administração & dosagem , Macrófagos/efeitos dos fármacos , Células Supressoras Mieloides/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Animais , Antígenos B7/genética , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Injeções Intravenosas , Lipossomos , Ativação Linfocitária/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fenótipo , Ratos Wistar , Linfócitos T/imunologia , Linfócitos T/metabolismo
2.
J Immunol Methods ; 454: 89, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29455735

RESUMO

Antibody-mediated phagocytosis of platelets using a flow cytometric monocyte-based phagocytosis assay (FMPA) has been shown to predict the outcome of platelet transfusion. The easy adherence between platelets and monocytes even in the absence of an antibody is regarded as one of limitations of the FMPA. To improve the FMPA for prediction of transfusion outcome, we used the pH-sensitive dye pHrodo succinimidyl ester (pHrodo-SE), which has weak fluorescence at neutral pH and has increased fluorescence intensity in low pH conditions such as in lysomes. Platelets stained with pHrodo-SE were sensitized with an HLA class I monoclonal antibody (w6/32 clone) or anti-HLA class I containing antisera. The platelets were incubated with monocyte-enriched mononuclear cells. Phagocytic activity was assessed by the percentage of monocytes that phagocytosed platelets. Sensitization of platelets with w6/32 significantly increased platelet phagocytosis by monocytes in dose- and time-dependent manners. Anti-HLA class I antibody-containing sera caused platelet phagocytosis in a cognate antigen-antibody-dependent manner. There was a significant correlation (r=0.69, p<0.01) between phagocytic index and titer of HLA class I antibody measured by lymphocyte immunofluorescence test-flow cytometry. In addition, the phagocytic index obtained by FMPA with pHrodo-SE was significantly higher than that obtained by FMPA with the previously used dye, carboxyfluorescein diacetate succinimidyl ester, when platelets were sensitized by w6/32 and anti-HLA class I antibody-containing sera. Because of the higher resolution and higher sensitivity than those of the previous method, the pHrodo-SE-based FMPA may be suitable for more precise quantitation of phagocytosis activity, which would enable qualitative evaluation of transfusion effectiveness.

3.
J Funct Biomater ; 8(3)2017 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-28657582

RESUMO

Hemoglobin vesicles (HbVs) are oxygen carriers consisting of Hb molecules and liposome in which human hemoglobin (Hb) molecules are encapsulated. Investigations of HbV biocompatibility have shown that HbVs have no significant effect on either the quality or quantity of blood components such as RBC, WBC, platelets, complements, or coagulation factors, reflecting its excellent biocompatibility. However, their effects on the immune system remain to be evaluated. HbVs might affect the function of macrophages because they accumulate in the reticuloendothelial system. Results show that splenic T cell proliferation is suppressed after injection of not only HbV but also empty liposome into rat, and show that macrophages that internalized liposomal particles are responsible for the suppression. However, the effect is transient. Antibody production is entirely unaffected. Further investigation revealed that those macrophages were similar to myeloid-derived suppressor cells (MDSCs) in terms of morphology, cell surface markers, and the immune-suppression mechanism. Considering that MDSCs appear in various pathological conditions, the appearance of MDSC-like cells might reflect the physiological immune system response against the substantial burden of liposomal microparticles. Therefore, despite the possible induction of immunosuppressive cells, HbVs are an acceptable and promising candidate for use as a blood substitute in a clinical setting.

4.
J Immunol Methods ; 447: 57-64, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28472622

RESUMO

Antibody-mediated phagocytosis of platelets using a flow cytometric monocyte-based phagocytosis assay (FMPA) has been shown to predict the outcome of platelet transfusion. The easy adherence between platelets and monocytes even in the absence of an antibody is regarded as one of limitations of the FMPA. To improve the FMPA for prediction of transfusion outcome, we used the pH-sensitive dye pHrodo succinimidyl ester (pHrodo-SE), which has weak fluorescence at neutral pH and has increased fluorescence intensity in low pH conditions such as in lysomes. Platelets stained with pHrodo-SE were sensitized with an HLA class I monoclonal antibody (w6/32 clone) or anti-HLA class I containing antisera. The platelets were incubated with monocyte-enriched mononuclear cells. Phagocytic activity was assessed by the percentage of monocytes that phagocytosed platelets. Sensitization of platelets with w6/32 significantly increased platelet phagocytosis by monocytes in dose- and time-dependent manners. Anti-HLA class I antibody-containing sera caused platelet phagocytosis in a cognate antigen-antibody-dependent manner. There was a significant correlation (r=0.69, p<0.01) between phagocytic index and titer of HLA class I antibody measured by lymphocyte immunofluorescence test-flow cytometry. In addition, the phagocytic index obtained by FMPA with pHrodo-SE was significantly higher than that obtained by FMPA with the previously used dye, carboxyfluorescein diacetate succinimidyl ester, when platelets were sensitized by w6/32 and anti-HLA class I antibody-containing sera. Because of the higher resolution and higher sensitivity than those of the previous method, the pHrodo-SE-based FMPA may be suitable for more precise quantitation of phagocytosis activity, which would enable qualitative evaluation of transfusion effectiveness.


Assuntos
Plaquetas/fisiologia , Citometria de Fluxo/métodos , Monócitos/fisiologia , Transfusão de Plaquetas , Tipagem e Reações Cruzadas Sanguíneas , Corantes Fluorescentes , Antígenos HLA/imunologia , Humanos , Concentração de Íons de Hidrogênio , Isoantígenos/imunologia , Masculino , Fagocitose , Prognóstico , Resultado do Tratamento
5.
Immunopharmacol Immunotoxicol ; 39(3): 140-147, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28378599

RESUMO

CONTEXT: Myeloid-derived suppressor cells (MDSCs) are a subset of immature myeloid cells that function as immunosuppressive cells in various pathological conditions. Membrane-derived microvesicles are thought to be involved in MDSC induction. Earlier reports have described that injection of considerable amount of liposome into rat can suppress Con A-induced splenic T-cell proliferation. Liposome-internalized cells expressing CD11b/c suppress T-cell proliferation. Nitric oxide (NO) appears to be involved in the suppression. We speculated that, similarly to membrane-derived microvesicles, liposomal microparticles can induce MDSC-like cells in vivo. OBJECTIVES: To confirm our speculation we investigated dose-dependency of the suppressive effect, the effect of liposome on the induction of inducible NO synthase (iNOS), and anti-CD3 antibody-stimulated T-cell proliferation and cytokine production. MATERIALS AND METHODS: Liposome particles of 250 nm diameter were prepared and suspended in saline. Then, various amounts of liposomal suspension were injected intravenously into rats. After 24 h, rat spleens were removed and concanavalin A (or anti-CD3 antibody) stimulated-splenic T-cell proliferation and the production of iNOS, NO and cytokines were evaluated. RESULTS: T-cell proliferation was suppressed dose-dependently by liposome injection. The immunosuppressive cell exerts its suppressive activity in a dose-dependent manner. The suppression was eliminated by iNOS inhibitor. iNOS was detected in liposome-loaded splenocytes. Anti-CD3 antibody-stimulated T-cell proliferation was also inhibited. Enhanced production of IL-10 was observed. CONCLUSIONS: Liposomal microparticles can induce MDSC-like cells in vivo. The lipids which comprise liposomes might serve an important role in the induction of MDSCs in vivo.


Assuntos
Micropartículas Derivadas de Células/imunologia , Lipossomos/farmacologia , Células Mieloides/imunologia , Animais , Complexo CD3/imunologia , Concanavalina A/farmacologia , Citocinas/imunologia , Masculino , Células Mieloides/citologia , Óxido Nítrico/imunologia , Óxido Nítrico Sintase Tipo II/imunologia , Ratos , Ratos Endogâmicos WKY , Linfócitos T/citologia , Linfócitos T/imunologia
7.
Transfusion ; 54(12): 3173-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24894348

RESUMO

BACKGROUND: Volume-reduced washed platelets (VR-wPLTs), which are prepared by concentrating platelets (PLTs) into a smaller volume of additive solution (AS), may prevent not only circulatory overload, but also adverse reactions caused by plasma components. Although VR-wPLTs may be quickly degraded due to high PLT concentrations, few studies have examined the effects of storage on VR-wPLTs. We examined here the in vitro properties of VR-wPLTs prepared with M-sol AS during their storage for 7 days. STUDY DESIGN AND METHODS: Platelet concentrates (PCs) were divided into two equal aliquots (control group and test group). After the centrifugation of both aliquots and removal of as much supernatant as possible, the pellet of the control group was resuspended in 160 mL of M-sol while that of the test group was resuspended in 80 or 40 mL of M-sol. The wPLTs of both groups were stored in polyolefin bags with agitation at 20 to 24°C for 7 days. RESULTS: The pH values of both groups were maintained at higher than 7.0 during the 7-day storage. Differences in %disk, CD62P, annexin V, percent hypotonic shock response, and aggregation values between the test group and control group were small for at least 2 days after washing. CONCLUSIONS: The in vitro properties of VR-wPLTs were not markedly degraded for at least 2 days. Therefore, the storage properties of PLTs may be maintained in VR-wPLTs prepared at blood centers until they are administered to patients in hospitals.


Assuntos
Plaquetas/citologia , Preservação de Sangue/métodos , Plaquetas/metabolismo , Preservação de Sangue/instrumentação , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Soluções Farmacêuticas/farmacologia , Fatores de Tempo
8.
Artif Organs ; 38(3): 234-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24033558

RESUMO

Hemoglobin vesicles (HbVs), artificial oxygen carriers encapsulating concentrated Hb solution on phospholipid vesicles (liposomes), are promising candidates for clinically useful transfusion. Although HbV infusion transiently suppressed the proliferative response of rat splenic T-cells to concanavalin A or keyhole limpet hemocyanin (KLH), a T-cell-dependent antigen, in ex vivo culture conditions, HbV infusion did not affect the primary IgG antibody response. We extended our assessment of the effects of HbV infusion on the systemic immune response using primary and secondary responses to KLH in rats. We observed that the generation of primary anti-KLH IgM antibody in HbV-infused rats was not suppressed but was instead higher than those in saline-infused rats. Furthermore, HbV infusion did not suppress the increase of IgG subclass of KLH antibody in secondary response. The T cell response to KLH of bulk spleen cells, as derived from 2-3 months after secondary KLH immunization, was unaffected by infusion of HbV, suggesting that HbV loading has no suppressive effect on homeostatic survival of memory T-cells against KLH. These results indicate that HbV is highly biocompatible in systemic immune responses in rats.


Assuntos
Hemocianinas/farmacologia , Hemoglobinas/farmacologia , Baço/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Animais , Masculino , Ratos , Baço/citologia , Linfócitos T/citologia
11.
J Am Chem Soc ; 133(10): 3246-8, 2011 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-21341767

RESUMO

Infectious hepatitis B virus (HBV), namely Dane particles (DPs), consists of a core nucleocapsid including genome DNA covered with an envelope of hepatitis B surface antigen (HBsAg). We report the synthesis, structure, and HBV-trapping capability of multilayered protein nanotubes having an anti-HBsAg antibody (HBsAb) layer as an internal wall. The nanotubes were prepared using an alternating layer-by-layer assembly of human serum albumin (HSA) and oppositely charged poly-L-arginine (PLA) into a nanoporous polycarbonate (PC) membrane (pore size, 400 nm), followed by depositions of poly-L-glutamic acid (PLG) and HBsAb. Subsequent dissolution of the PC template yielded (PLA/HSA)(2)PLA/PLG/HBsAb nanotubes (AbNTs). The SEM measurements revealed the formation of uniform hollow cylinders with a 414 ± 16 nm outer diameter and 59 ± 4 nm wall thickness. In an aqueous medium, the swelled nanotubes captured noninfectious spherical small particles of HBsAg (SPs); the binding constant was 3.5 × 10(7) M(-1). Surprisingly, the amount of genome DNA in the HBV solution (HBsAg-positive plasma or DP-rich solution) decreased dramatically after incubation with the AbNTs (-3.9 log order), which implies that the infectious DPs were completely entrapped into the one-dimensional pore space of the AbNTs.


Assuntos
Anticorpos Anti-Hepatite B/química , Vírus da Hepatite B/isolamento & purificação , Nanotubos/química , Albumina Sérica/química , Anticorpos Anti-Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Humanos , Albumina Sérica/imunologia
12.
J Pharmacol Exp Ther ; 337(1): 42-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21212161

RESUMO

Liposomes reportedly accumulate in monophagocytic systems (MPSs), such as those of the spleen. Accumulation of considerable amounts of liposome in a MPS can affect immunologic response. While developing a liposomal oxygen carrier containing human hemoglobin vesicle (HbV), we identified its suppressive effect on the proliferation of rat splenic T cells. The aim of this study was to elucidate the mechanism underlying that phenomenon and its effect on both local and systemic immune response. For this study, we infused HbV intravenously at a volume of 20% of whole blood or empty liposomes into rats, removed their spleens, and evaluated T cell responses to concanavalin A (Con A) or keyhole limpet hemocyanin (KLH) by measuring the amount of [(3)H]thymidine incorporated into DNA. Cells that phagocytized liposomal particles were sorted using flow cytometry and analyzed. Serum anti-KLH antibody was measured after immunizing rats with KLH. Results showed that T cell proliferation in response to Con A or KLH was inhibited from 6 h to 3 days after the liposome injection. Direct cell-to-cell contact was necessary for the suppression. Both inducible nitric-oxide synthase and arginase inhibitors restored T cell proliferation to some degree. The suppression abated 7 days later. Cells that trapped vesicles were responsible for the suppression. Most expressed CD11b/c but lacked class II molecules. However, the primary antibody response to KLH was unaffected. We conclude that the phagocytosis of the large load of liposomal particles by rat CD11b/c+, class II immature monocytes temporarily renders them highly immunosuppressive, but the systemic immune response was unaffected.


Assuntos
Diferenciação Celular/imunologia , Tolerância Imunológica/imunologia , Lipossomos/imunologia , Monócitos/imunologia , Fagocitose/fisiologia , Baço/citologia , Baço/imunologia , Animais , Técnicas de Cultura de Células , Hemoglobinas/metabolismo , Lipossomos/metabolismo , Masculino , Monócitos/citologia , Monócitos/metabolismo , Tamanho da Partícula , Ratos , Baço/metabolismo , Fatores de Tempo
13.
Transfusion ; 51(5): 993-1001, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20977481

RESUMO

BACKGROUND: HLA Class II antibody-initiated activation of monocytes possessing the corresponding antigen is thought to participate in the pathogenesis of transfusion-related acute lung injury (TRALI). Pulmonary edema, a hallmark of TRALI, is caused by increasing vascular permeability. STUDY DESIGN AND METHODS: To investigate the contribution of HLA Class II antibody and monocytes to the development of pulmonary edema in TRALI, we studied whether the permeability of human lung microvascular endothelial cells (HMVECs) could be enhanced by coculturing HMVECs with peripheral blood mononuclear cells (PBMNCs) in the presence of HLA Class II antibody-containing plasma, which was implicated in TRALI (anti-HLA-DR plasma). In addition, similar experiments were performed with human umbilical vein endothelial cells (HUVECs). The endothelial permeability to fluoresceinated dextran, which was added from the start of coculture, was measured. RESULTS: The coculture of HMVECs or HUVECs with PBMNCs in the presence of anti-HLA-DR plasma resulted in the increase of endothelial permeability in the corresponding antigen-antibody-dependent manner. CV-3988, a platelet-activating factor (PAF) receptor antagonist, almost completely suppressed the increase in endothelial permeability. Neutralizing antibodies to tumor necrosis factor (TNF)-α alone and simultaneous addition of the antibodies to TNF-α and interleukin (IL)-1ß to the coculture partially suppressed the permeability increase of HMVECs and HUVECs, respectively. CONCLUSIONS: HLA Class II antibody and monocytes in the corresponding antigen-antibody combination caused the enhancement of endothelial permeability. PAF, TNF-α, and/or IL-1ß might be involved in the endothelial permeability increase. HLA Class II antibody-initiated monocyte activation could lead to the development of pulmonary edema in TRALI.


Assuntos
Lesão Pulmonar Aguda/imunologia , Células Endoteliais/imunologia , Antígenos HLA-DR/imunologia , Leucócitos Mononucleares/imunologia , Reação Transfusional , Lesão Pulmonar Aguda/etiologia , Idoso , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Permeabilidade Capilar/imunologia , Técnicas de Cocultura , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Masculino , Glicoproteínas da Membrana de Plaquetas/antagonistas & inibidores , Glicoproteínas da Membrana de Plaquetas/imunologia , Edema Pulmonar/etiologia , Edema Pulmonar/imunologia , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/imunologia , Receptores de Leucotrienos/imunologia , Veias Umbilicais/citologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-20626230

RESUMO

A higher production of functional mast cells (MCs) can be generated by co-culturing cord blood-derived CD34+ cells with a human bone marrow stromal cell line under serum-free conditions supplemented with stem cell factor and IL-6. We addressed the question of whether the higher proliferation of MCs in this co-culture system might be due to the higher proliferation of MC progenitors. The stromal cell line increased the cell numbers of MC progenitors derived from cord blood-derived CD34+ cells, in a combination of cell-cell interactions between stromal cells and CD34+ cells, and as yet unidentified soluble factors derived from stromal cells.


Assuntos
Proliferação de Células , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , Interleucina-6/metabolismo , Mastócitos/citologia , Fator de Células-Tronco/metabolismo , Antígenos CD34/metabolismo , Comunicação Celular , Células Cultivadas , Técnicas de Cocultura/métodos , Meios de Cultivo Condicionados , Meios de Cultura Livres de Soro , Sangue Fetal/imunologia , Humanos , Mastócitos/metabolismo , Células-Tronco Mesenquimais/citologia , Células Estromais/citologia , Células Estromais/metabolismo
16.
Transfusion ; 49(8): 1754-61, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19392771

RESUMO

BACKGROUND: Type I allergic reactions such as urticaria-like manifestations constitute a large percentage of transfusion-related adverse events. Along with donor factors, patient factors might be involved in these reactions. Sera from some patients with chronic idiopathic urticaria show histamine-releasing activity (HRA). Sera from patients who develop Type I allergic reaction might possess HRA. STUDY DESIGN AND METHODS: Pretransfusion serum samples were collected. Mast cells were cultured from peripheral blood CD34+ cells and mixed with the serum samples. Cells with elevated intracytoplasmic Ca2+ concentrations were monitored using flow cytometry to evaluate Ca2+ influx-inducing activity (CaIA) in serum. The amount of histamine released into the supernatant was measured using an enzyme immunoassay kit to evaluate HRA. In some assays, cells were incubated with pertussis toxin (Ptx). RESULTS: CaIA values were higher (p < 0.05) in sera from patients with reactions (27.68 ± 20.38 [n = 145]; range, 0.49-84.90) than in sera of patients without reactions (10.70 ± 6.50 [n = 54]; range, 2.67-36.97) and control sera (9.67 ± 5.88 [n = 107]; range, 1.11-25.68). No difference in CaIA was found between patients with (27.38 ± 20.46 [n = 88]) and without (28.38 ± 20.59 [n = 57]) skin manifestations. However, CaIA was higher (p < 0.05) in patients with pure urticaria (mean, 30.58 ± 21.3 [n = 30]; range, 70.43-4.1) than in patients with fever alone (mean, 18.61 ± 14.71 [n = 18]; range, 45.94-3.19). Levels of HRA were higher (p < 0.001) in CaIA-positive sera than in CaIA-negative sera. Both CaIA and HRA were blocked by Ptx. CONCLUSION: Elevated CaIA and HRA in pretransfusion sera might be attributable to adverse reactions, especially to urticaria-like manifestation. The Gi protein-coupled receptor complexes on mast cells and its ligand must be involved.


Assuntos
Antígenos CD34 , Cálcio/metabolismo , Histamina/sangue , Mastócitos/metabolismo , Reação Transfusional , Urticária/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Técnicas de Cocultura , Feminino , Citometria de Fluxo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Toxina Pertussis/farmacologia , Urticária/etiologia
17.
ASAIO J ; 55(3): 200-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19282747

RESUMO

Hemoglobin vesicles (HbVs), liposomal oxygen carriers containing human hemoglobin, are candidates for development of a clinically useful transfusion alternative. Our previous in vivo animal studies of massive HbV dosages demonstrated the lack of any suppressive effect on hematopoiesis. Before starting clinical trials, we aimed to examine the details of the biocompatibility of HbVs with human hematopoietic stem/progenitor cells. We investigated the effect of HbVs at a concentration of up to 3 vol/vol (%) on expansion of human umbilical cord (CB) hematopoietic stem/progenitor cells, using a coculture system of human TERT-transfected bone marrow stromal cells and CD34+ cells in vitro. The exposure of CB CD34+ cells to HbVs up to 14 days suppressed the expansion of total cells and the CD34+ cells themselves, whereas the empty liposomes, that did not contain Hb, had modestly inhibitory effects on the expansion of these cells. As a result, the number of colonies obtained from the expanded CD34+ cells was inhibited by the exposure to HbVs. In contrast, exposure to HbVs for 3 days had no effect on the expansion of CD34+ cells and only slightly decreased the number of total cells. Our in vitro experimental condition does not fully recreate the physiological condition, and the effect of the direct contact of HbV would be magnified because of the absence of shielding by the vasculature and the lack of the reticuloendothelial system and blood stream. However, the present data raise some concern regarding hematopoiesis, and one has to pay attention to this in future human clinical trials.


Assuntos
Materiais Biocompatíveis/administração & dosagem , Substitutos Sanguíneos/administração & dosagem , Células-Tronco Hematopoéticas/fisiologia , Hemoglobinas/administração & dosagem , Antígenos CD34/metabolismo , Proliferação de Células , Técnicas de Cocultura , Sangue Fetal , Humanos , Lipossomos , Teste de Materiais , Oxigênio , Células Estromais/fisiologia , Telomerase/genética , Transfecção
18.
Transfusion ; 49(2): 214-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18798806

RESUMO

BACKGROUND: Leukodepletion reduces but does not eliminate adverse reactions to platelet concentrate (PC). As an alternative strategy, plasma reduction or washing of platelets should be considered. However, the efficacy of this strategy is still unclear. STUDY DESIGN AND METHODS: A total of 12 patients who experienced adverse reactions at a 29 to 100 percent reaction rate for plasma-PC were enrolled. The reactions were allergic reactions and nonhemolytic transfusion reactions, such as chills. Plasma-removed PC (W/R-PC), which was suspended in a recently developed additive solution (M-sol) containing less than 20 mL plasma, was prepared. W/R-PCs in M-sol were then transfused into patients after an overnight storage period; the occurrence of adverse reactions was monitored and 1- and 24-hour corrected count increment (CCI) values were evaluated. RESULTS: Although plasma-PC caused reaction in 12 patients, W/R-PC prevented reactions in 11 of 12 patients, with 1 patient having one minor allergic reaction of 15 transfusions. There was a significant difference in the incidence of reaction (p < 0.0001, Fisher's exact test). On a per-transfusion basis, the reaction rate for W/R-PC (1/156, 0.64%; 95% confidence interval [CI], 0.02%-3.5%) was reduced significantly compared to that for plasma-PC (117/276, 42%; 95% CI, 36%-48%; p < 0.0001). W/R-PC gave findings of satisfactory CCI at 1 hour (22,400 +/- 8,000/microL) and 24 hours (15,400 +/- 8,000/microL). No clinically evident bleeding episodes were recorded. CONCLUSIONS: W/R-PC suspended in M-sol in the presence of less than 20 mL plasma can be transfused safely and eliminate a wide range of adverse reactions to plasma-PC.


Assuntos
Plaquetas , Preservação de Sangue , Hipersensibilidade/prevenção & controle , Soluções Isotônicas/uso terapêutico , Soluções para Preservação de Órgãos/uso terapêutico , Transfusão de Plaquetas/efeitos adversos , Humanos , Hipersensibilidade/etiologia , Plasma , Contagem de Plaquetas/métodos , Fatores de Tempo , Resultado do Tratamento
19.
J Biomed Mater Res A ; 88(1): 34-42, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18257068

RESUMO

Hemoglobin vesicles (HbVs), liposomal oxygen carriers containing human hemoglobin, are candidates for development as clinically useful blood substitutes. Although HbVs are shown to distribute transiently into the bone marrow in animal models, the influence of HbVs on human hematopoietic stem/progenitor cells has not yet been studied. Therefore, we investigated the influence of HbVs at a concentration of up to 3 vol/vol % on the clonogenic activity (in semisolid culture) and proliferative activity (in liquid culture) of human hematopoietic progenitor cells derived from umbilical cord blood (CB) in vitro. Continuous exposure of CB mononuclear cells to HbVs tended to decrease the number and size of mature-committed colonies and most notably reduced the number of colonies of high-proliferative potential colony-forming cells (HPP-CFC). In contrast, exposure to HbVs for 20 h or 3 days, which is more relevant to the clinical setting, had no effect on the number of mature-committed colonies and only modestly decreased the number of HPP-CFC. Continuous exposure (10 days) to HbVs significantly suppressed the cellular proliferation and differentiation of both the erythroid and myeloid lineages in liquid culture. Again, short exposure (20 h or 3 days) did not affect these parameters. Thus, our results show that HbVs, under conditions relevant to the clinical setting, have no adverse effect on human CB hematopoietic progenitor activity in vitro.


Assuntos
Substitutos Sanguíneos/farmacologia , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , Hemoglobinas/farmacologia , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula , Proliferação de Células/efeitos dos fármacos , Sangue Fetal/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Lipossomos , Oxigênio/metabolismo , Fatores de Tempo
20.
Transfusion ; 48(10): 2060-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18564388

RESUMO

BACKGROUND: The generation of inflammatory mediators from monocytes activated by HLA Class II antibodies is thought to play important roles in the etiology of nonhemolytic transfusion reactions. Increased permeability of endothelial cells contributes to the pathogenesis of rash, urticaria, angioedema, and pulmonary edema, which are symptoms of transfusion reactions. STUDY DESIGN AND METHODS: We investigated whether inflammatory mediators released from monocytes upon stimulation by HLA Class II antibodies could increase endothelial permeability. Human endothelial cell monolayers were incubated with cell-free supernatants of peripheral blood mononuclear cells (PBMNCs) stimulated with HLA Class II antibody-containing plasma (anti-HLA-DR plasma), which has been implicated in severe nonhemolytic transfusion reactions. The permeability of endothelial cells to dextran was measured. RESULTS: The supernatants of PBMNCs stimulated with the anti-HLA-DR plasma in corresponding antigen-antibody combinations were able to increase endothelial permeability. At least 3 hours of exposure of PBMNCs to anti-HLA-DR plasma was required to produce a supernatant that could induce a significant increase in permeability. Simultaneous addition of tumor necrosis factor alpha (TNF-alpha) and interleukin 1 beta (IL-1 beta) neutralizing antibodies to the activated PBMNC supernatant significantly reduced the increase in permeability. Treatment of the endothelial cells with an inhibitor of nuclear factor kappaB (NF-kappaB), but not inhibitors of apoptosis, significantly prevented the increase in permeability. CONCLUSION: Both TNF-alpha and IL-1 beta, generated from PBMNCs by anti-HLA-DR plasma in a corresponding antigen-antibody-dependent manner, led to an increase in endothelial permeability. The activation of monocytes by the HLA-DR antibodies and the resultant inflammatory mediators could contribute to the pathogenesis of rash, urticaria, angioedema, and pulmonary edema after transfusion.


Assuntos
Anticorpos/imunologia , Reações Antígeno-Anticorpo/imunologia , Células Endoteliais/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Leucócitos Mononucleares/imunologia , Anticorpos/farmacologia , Capilares/citologia , Capilares/imunologia , Permeabilidade Capilar/imunologia , Células Cultivadas , Células Endoteliais/citologia , Antígenos HLA-DR/imunologia , Humanos , Interleucina-1beta/imunologia , Leucócitos Mononucleares/citologia , Testes de Neutralização , Transdução de Sinais/imunologia , Reação Transfusional , Fator de Necrose Tumoral alfa/imunologia , Veias Umbilicais/citologia
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