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1.
Article in English | MEDLINE | ID: mdl-36142014

ABSTRACT

OBJECTIVE: The purpose of this mixed methods study was to explore the impact of COVID-19 on the ability of people with Parkinson disease (PwPs) and their care-partners to perform food-related activities (FRA) and PwPs' overall diet quality. METHODS: Using a convergent parallel mixed methods design, PwPs and their care-partners completed virtual dyadic semi-structured interviews about their FRA during the COVID-19 pandemic. PwPs completed Food Frequency Questionnaires (FFQ) to quantify their dietary intake in the previous 12 months. Qualitative data were analyzed by two coders using thematic analysis, and quantitative data from FFQs were descriptively analyzed to calculate diet quality scores. RESULTS: Eleven dyadic interviews revealed the following key themes: cooking more at home; changes with grocery shopping; less meals with non-household members. These changes were described to increase the care-partners' responsibilities and overall burden. Diet scores among PwPs were 73.0 ± 6.3 for the Healthy Eating Index 2015 (scale of 0-100), 29.2 ± 6.6 for the Mediterranean diet (scale of 0-55), and 10.4 ± 1.8 for the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet (scale 0-15). CONCLUSIONS: Diet scores revealed that PwPs consumed a high-quality diet during the pandemic. Findings from this study highlight the need for tailored nutrition education to support PwPs' care-partners.


Subject(s)
COVID-19 , Diet, Mediterranean , Parkinson Disease , COVID-19/epidemiology , Diet , Feeding Behavior , Humans , Meals , Pandemics , Parkinson Disease/epidemiology
2.
Sci Rep ; 12(1): 10976, 2022 06 29.
Article in English | MEDLINE | ID: mdl-35768621

ABSTRACT

In relapsed and refractory multiple myeloma (RRMM), there are few treatment options once patients progress from the established standard of care. Several bispecific T-cell engagers (TCE) are in clinical development for multiple myeloma (MM), designed to promote T-cell activation and tumor killing by binding a T-cell receptor and a myeloma target. In this study we employ both computational and experimental tools to investigate how a novel trispecific TCE improves activation, proliferation, and cytolytic activity of T-cells against MM cells. In addition to binding CD3 on T-cells and CD38 on tumor cells, the trispecific binds CD28, which serves as both co-stimulation for T-cell activation and an additional tumor target. We have established a robust rule-based quantitative systems pharmacology (QSP) model trained against T-cell activation, cytotoxicity, and cytokine data, and used it to gain insight into the complex dose response of this drug. We predict that CD3-CD28-CD38 killing capacity increases rapidly in low dose levels, and with higher doses, killing plateaus rather than following the bell-shaped curve typical of bispecific TCEs. We further predict that dose-response curves are driven by the ability of tumor cells to form synapses with activated T-cells. When competition between cells limits tumor engagement with active T-cells, response to therapy may be diminished. We finally suggest a metric related to drug efficacy in our analysis-"effective" receptor occupancy, or the proportion of receptors engaged in synapses. Overall, this study predicts that the CD28 arm on the trispecific antibody improves efficacy, and identifies metrics to inform potency of novel TCEs.


Subject(s)
Antibodies, Bispecific , Multiple Myeloma , CD28 Antigens , CD3 Complex , Humans , Multiple Myeloma/drug therapy , Network Pharmacology , T-Lymphocytes
3.
Oncoimmunology ; 10(1): 1899469, 2021 03 18.
Article in English | MEDLINE | ID: mdl-33796409

ABSTRACT

Targeted immunotherapy of solid cancers with chimeric antigen receptor (CAR) T cells and immunocytokines are attractive options in that they both rely on the specificity of tumor-targeted antibodies. Since carcinoembryonic antigen (CEA) expression in both colon and breast cancers is correlated with poor prognosis, it was chosen as a model tumor target in immunocompetent CEA transgenic (CEATg) mice. A second-generation anti-CEA CAR derived from CEA-specific antibody T84.66 was used to treat murine MC38 colon or E0771 breast carcinomas transfected with CEA. Anti-CEA CAR vs. mock transduced T cells exhibited a CEA-specific cytotoxic and IFN γ dose response to both CEA transfected cell lines vs. their CEA-negative controls. Anti-CEA CAR vs. mock transduced T cells delayed the median survival of CEA transfected s.c. MC38 or orthotopic E0771 tumor-bearing CEATg mice by 2 days. With the addition of one-day prior cyclophosphamide (CY) lymphodepletion, anti-CEA CAR T cell treatment delayed the median survival of MC38/CEA and E0771/CEA tumor-bearing CEATg mice by ten and 3 days, respectively. Since CAR T cells require IL2 for survival and expansion, anti-CEA-IL2 immunocytokine (ICK) treatment was performed post CAR T cell therapy. Single ICK treatment 1 day after CY plus anti-CEA CAR T cell therapy in the MC38/CEA model, and two ICK treatments every 3 days after CY plus anti-CEA CAR T cell therapy in the E0771/CEA model were ineffective, while four ICK treatments every 3 days after CY plus anti-CEA CAR T cell therapy completely eradicated MC38/CEA tumor growth and induced tumor immunity when the mice were re-challenged with tumor. These studies show the therapeutic potential of anti-CEA CAR T cells combined with ICK to treat CEA-positive tumors. Abbreviations: CAR: Chimeric antigen receptor, CEA: Carcinoembryonic antigen, CEACAM5, ICK: Immunocytokine, CY: Cyclophosphamide, CEATg mouse: transgenic CEA mouse, TDLN: Tumor-draining lymph node.


Subject(s)
Immunotherapy, Adoptive , Neoplasms , Receptors, Chimeric Antigen , Animals , Carcinoembryonic Antigen/genetics , Interleukin-2 , Mice , Neoplasms/therapy , T-Lymphocytes
4.
Histopathology ; 77(3): 402-412, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32473032

ABSTRACT

AIMS: Histology-based tumour microenvironment (TME) scores are useful in predicting the prognosis of gastrointestinal cancer. However, their prognostic roles in distal bile duct cancer (DBDC) have not been previously studied. This study aimed to evaluate the prognostic significance of the TME scores using the Klintrup-Mäkinen (KM) grade, tumour stroma percentage (TSP) and the Glasgow microenvironment score (GMS) in resected DBDC. METHODS AND RESULTS: Eighty-one patients with DBDC who underwent curative resection were enrolled. DBDC was graded according to KM grade, TSP and GMS. A high KM grade was found in 19 patients (24%) and a high TSP was found in 47 patients (58%). A high TSP was significantly correlated with a low KM grade (P < 0.001). The distribution of the GMS, which was developed by combining the KM grade and TSP, was as follows: 0 (n = 19, 24%), 1 (n = 19, 24%) and 2 (n = 43, 52%). A low KM grade, high TSP and high GMS were significantly associated with short overall survival (OS) (P < 0.001) and relapse-free survival (RFS) (P < 0.001). Furthermore, multivariate analysis showed that a low KM grade [hazard ratio (HR) = 3.826; confidence interval (CI) = 1.650-8.869; P = 0.014], high TSP (HR = 2.193; CI = 1.173-4.100, P = 0.002) and high GMS (HR = 7.148; CI = 2.811-18.173) were independent prognostic factors for short RFS; a low KM grade (HR = 4.324; CI = 1.594-11.733) and high GMS (HR = 6.332; CI = 2.743-14.594) were independent prognostic factors for short OS. CONCLUSION: Histology-based TME scores, including the KM grade, TSP and GMS, are useful for predicting the survival of patients with resected DBDC.


Subject(s)
Adenocarcinoma/pathology , Bile Duct Neoplasms/pathology , Neoplasm Grading/methods , Tumor Microenvironment , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prognosis
5.
J Nurse Pract ; 15(5): 365-369, 2019 May.
Article in English | MEDLINE | ID: mdl-31700501

ABSTRACT

Diabetes is highly prevalent in African American men. To provide nurse practitioners with practice strategies we explored African American men's perceived needs for dietary health and diabetes self-management using the Social Cognitive Theory. Twenty-five African American men participated in four focus groups. The data were analyzed using a combination of inductive/deductive content analysis approach. Focus group analysis identified personal, behavioral and environmental barriers to and facilitators for diabetes self-management. Nurse practitioners may need to provide extra emotional support in the absence of informal social support from families for diabetes self-management and dietary health in African American men with diabetes.

6.
Int Wound J ; 16(1): 286-296, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30461211

ABSTRACT

The potential use of extracellular matrix (ECM) as a source of wound dressing material has recently received much attention. The ECM is an intricate network of various combinations of elastin, collagens, laminin, fibronectin, and proteoglycans that play a key role in stimulating cell proliferation and differentiation. We evaluated the efficacy of an ECM sheet derived from human adipose tissue as a wound dressing material to enhance healing. We prepared a novel porous ECM sheet dressing scaffold from human adipose tissue. in vitro analysis of the ECM sheets showed efficient decellularisation; absence of immunostimulatory components; and the presence of a wide number of angiogenic and bioactive factors, including collagen, elastin, and proteoglycans. To evaluate in vivo efficacy, full-thickness excisional wounds were created on the dorsal skin of a rat, and the ECM sheets; secondary healing foam wound dressing, Healoderm; or a conventional dressing were applied to each wound site. Photographs were taken every other day, and the degree of reepithelialisation of the wounds was determined. Application of an ECM sheet dressing enhanced the macroscopic wound-healing rate on days 4, 7, and 10 compared with that in the control group. Microscopic analysis indicated that the reepithelialisation rate of the wound was higher in the ECM group compared with that in the control group; the reepithelialisation rate was better than that of the secondary healing foam wound dressing. Moreover, a denser and more organised granulation tissue was formed in the ECM sheet group compared with that in the secondary healing foam wound dressing and control groups. The ECM sheet also showed the highest microvessel density compared with the secondary healing foam wound dressing and control groups. Based on these data, we suggest that a bioactive ECM sheet dressing derived from human adipose can provide therapeutic proteins for wound healing.


Subject(s)
Adipose Tissue/transplantation , Extracellular Matrix/transplantation , Skin/anatomy & histology , Skin/growth & development , Stem Cell Transplantation/methods , Wound Healing/physiology , Wounds and Injuries/therapy , Animals , Histological Techniques , Humans , Immunohistochemistry/methods , Male , Models, Animal , Rats , Rats, Sprague-Dawley , Republic of Korea
7.
Front Immunol ; 9: 1938, 2018.
Article in English | MEDLINE | ID: mdl-30210495

ABSTRACT

Given the importance of high-mobility group box 1 (HMGB1) and 5-lipoxygenase (5-LO) signaling in vascular inflammation, we investigated the role of leukotriene signaling in monocytes on monocyte-to-macrophage differentiation (MMD) induced by HMGB1, and on vascular inflammation and subsequent intimal hyperplasia in a mouse model of wire-injured femoral artery. In cultured primary bone marrow-derived cells (BMDCs) stimulated with HMGB1, the number of cells with macrophage-like morphology was markedly increased in association with an increased expression of CD11b/Mac-1, which were attenuated in cells pre-treated with Zileuton, a 5-LO inhibitor as well as in 5-LO-deficient BMDCs. Of various leukotriene receptor inhibitors examined, which included leukotriene B4 receptors (BLTRs) and cysteinyl leukotriene receptors (cysLTRs), the BLTR1 inhibitor (U75302) exclusively suppressed MMD induction by HMGB1. The importance of BLTR1 in HMGB1-induced MMD was also observed in BMDCs isolated from BLTR1-deficient mice and BMDCs transfected with BLTR1 siRNA. Although leukotriene B4 (LTB4) had minimal direct effects on MMD in control and 5-LO-deficient BMDCs, MMD attenuation by HMGB1 in 5-LO-deficient BMDCs was significantly reversed by exogenous LTB4, but not in BLTR1-deficient BMDCs, suggesting that LTB4/BLTR1-mediated priming of monocytes is a prerequisite of HMGB1-induced MMD. In vivo, both macrophage infiltration and intimal hyperplasia in our wire-injured femoral artery were markedly attenuated in BLTR1-deficient mice as compared with wild-type controls, but these effects were reversed in BLTR1-deficient mice transplanted with monocytes from control mice. These results suggest that BLTR1 in monocytes is a pivotal player in MMD with subsequent macrophage infiltration into neointima, leading to vascular remodeling after vascular injury.


Subject(s)
Fatty Alcohols/pharmacology , Femoral Artery , Glycols/pharmacology , Monocytes , Receptors, Leukotriene B4 , Vascular Remodeling , Vascular System Injuries , Vasculitis , Animals , Femoral Artery/immunology , Femoral Artery/injuries , Femoral Artery/pathology , Hyperplasia , Macrophages/immunology , Macrophages/pathology , Mice , Mice, Knockout , Monocytes/immunology , Monocytes/pathology , Receptors, Leukotriene B4/antagonists & inhibitors , Receptors, Leukotriene B4/genetics , Receptors, Leukotriene B4/immunology , Vascular Remodeling/drug effects , Vascular Remodeling/genetics , Vascular Remodeling/immunology , Vascular System Injuries/drug therapy , Vascular System Injuries/genetics , Vascular System Injuries/immunology , Vascular System Injuries/pathology , Vasculitis/drug therapy , Vasculitis/genetics , Vasculitis/immunology , Vasculitis/pathology
8.
Matrix Biol ; 32(2): 117-22, 2013 Mar 11.
Article in English | MEDLINE | ID: mdl-23201136

ABSTRACT

Microfibril-associated glycoprotein 2 (MAGP2) is a secreted protein associated with multiple cellular activities including the organization of elastic fibers in the extracellular matrix (ECM), angiogenesis, as well as regulating Notch and integrin signaling. Importantly, increases in MAGP2 positively correlate with poor prognosis for some ovarian cancers. It has been assumed that full-length MAGP2 is responsible for all reported effects; however, here we show MAGP2 is a substrate for the proprotein convertase (PC) family of endoproteases. Proteolytic processing of MAGP2 by PC cleavage could serve to regulate secretion and thus, activity and function as reported for other extracellular and cell-surface proteins. In support of this idea, MAGP2 contains an evolutionarily conserved PC consensus cleavage site, and amino acid sequencing of a newly identified MAGP2 C-terminal cleavage product confirmed functional PC cleavage. Additionally, mutagenesis of the MAGP2 PC consensus cleavage site or treatment with PC inhibitors prevented MAGP2 proteolytic processing. Finally, both cleaved and uncleaved MAGP2 were detected extracellularly and MAGP2 secretion appeared independent of PC cleavage, suggesting that PC processing occurs mainly outside the cell. Our characterization of alternative forms of MAGP2 present in the extracellular space not only enhances diversity of this ECM protein but also provides a previously unrecognized molecular mechanism for regulation of MAGP2 biological activity.


Subject(s)
Contractile Proteins/metabolism , Extracellular Matrix/metabolism , Glycoproteins/metabolism , Proprotein Convertases/metabolism , Proteolysis , Amino Acid Sequence , Cell Line , Contractile Proteins/genetics , Extracellular Matrix/genetics , Glycoproteins/genetics , Humans , Integrins , Intercellular Signaling Peptides and Proteins , Microfibrils/metabolism , Proprotein Convertases/genetics , Protein Isoforms/metabolism
9.
J Biomech ; 41(11): 2551-61, 2008 Aug 07.
Article in English | MEDLINE | ID: mdl-18656199

ABSTRACT

The blood flow dynamics of a stenosed, subject-specific, carotid bifurcation were numerically simulated using the spectral element method. Pulsatile inlet conditions were based on in vivo color Doppler ultrasound measurements of blood velocity. The results demonstrated the transitional or weakly turbulent state of the blood flow, which featured rapid velocity and pressure fluctuations in the post-stenotic region of the internal carotid artery (ICA) during systole and laminar flow during diastole. High-frequency vortex shedding was greatest downstream of the stenosis during the deceleration phase of systole. Velocity fluctuations had a frequency within the audible range of 100-300Hz. Instantaneous wall shear stress (WSS) within the stenosis was relatively high during systole ( approximately 25-45Pa) compared to that in a healthy carotid. In addition, high spatial gradients of WSS were present due to flow separation on the inner wall. Oscillatory flow reversal and low pressure were observed distal to the stenosis in the ICA. This study predicts the complex flow field, the turbulence levels and the distribution of the biomechanical stresses present in vivo within a stenosed carotid artery.


Subject(s)
Carotid Stenosis/physiopathology , Computer Simulation , Blood Flow Velocity/physiology
10.
J Biomech ; 40(9): 2096-106, 2007.
Article in English | MEDLINE | ID: mdl-17544431

ABSTRACT

It is now well established that cells can sense mechanical force, but the mechanisms by which force is transduced into a biochemical signal remain poorly understood. One example is the recruitment of vinculin to reinforce initial contacts between a cell and the extracellular matrix (ECM) due to tensile force. Talin, an essential linking protein in an initial contact, contains at least one vinculin-binding site (VBS) that is cryptic and inactive in the native state. The N-terminal five-helix bundle of talin rod is a stable structure with a known cryptic VBS1. The perturbation of this stable structure through elevated temperature or destabilizing mutation activates vinculin binding. Although the disruption of this subdomain by transmitted mechanical force is a potential cue for the force-induced focal adhesion strengthening, the molecular basis for this mechanism remains elusive. Here, molecular dynamics (MD) is employed to demonstrate a force-induced conformational change that exposes the cryptic vinculin-binding residues of VBS1 to solvent under applied force along a realistic pulling direction. VBS1 undergoes a rotation of 62.0 +/- 9.5 degrees relative to its native state as its vinculin-binding residues are released from the tight hydrophobic core. Charged and polar residues on the VBS1 surface are the site of force transmission that strongly interact with an adjacent alpha-helix, and in effect, apply torque to the VBS1 to cause its rotation. Activation was observed with mean force of 13.2 +/-8.0 pN during constant velocity simulation and with steady force greater than 18.0 pN.


Subject(s)
Focal Adhesions/physiology , Mechanotransduction, Cellular/physiology , Talin/metabolism , Amino Acid Substitution/genetics , Models, Biological , Models, Molecular , Talin/chemistry , Talin/genetics
11.
Biophys J ; 90(8): 2686-97, 2006 Apr 15.
Article in English | MEDLINE | ID: mdl-16443661

ABSTRACT

Force-induced changes in protein conformation are thought to be responsible for certain cellular responses to mechanical force. Changes in conformation subsequently initiate a biochemical response by alterations in, for example, binding affinity to another protein or enzymatic activity. Here, a model of protein extension under external forcing is created inspired by Kramers' theory for reaction rate kinetics in liquids. The protein is assumed to have two distinct conformational states: a relaxed state, C(1), preferred in the absence of external force, and an extended state, C(2), favored under force application. In the context of mechanotransduction, the extended state is a conformation from which the protein can initiate signaling. Appearance and persistence of C(2) are assumed to lead to transduction of the mechanical signal into a chemical one. The protein energy landscape is represented by two harmonic wells of stiffness kappa(1) and kappa(2), whose minima correspond to conformations C(1) and C(2). First passage time t(f) from C(1) to C(2) is determined from the Fokker-Plank equation employing several different approaches found in the literature. These various approaches exhibit significant differences in behavior as force increases. Although the level of applied force and the energy difference between states largely determine equilibrium, the dominant influence on t(f) is the height of the transition state. Distortions in the energy landscape due to force can also have a significant influence, however, exhibiting a weaker force dependence than exponential as previously reported, approaching a nearly constant value at a level of force that depends on the ratio kappa(1)/kappa(2). Two model systems are used to demonstrate the utility of this approach: a short alpha-helix undergoing a transition between two well-defined states and a simple molecular motor.


Subject(s)
Computer Simulation , Models, Biological , Molecular Motor Proteins/chemistry , Biomechanical Phenomena , Elasticity , Kinetics , Protein Conformation
12.
J Biomech Eng ; 125(1): 49-61, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12661196

ABSTRACT

We present experimental and computational results that describe the level, distribution, and importance of velocity fluctuations within the venous anastomosis of an arteriovenous graft. The motivation of this work is to understand better the importance of biomechanical forces in the development of intimal hyperplasia within these grafts. Steady-flow in vitro studies (Re = 1060 and 1820) were conducted within a graft model that represents the venous anastomosis to measure velocity by means of laser Doppler anemometry. Numerical simulations with the same geometry and flow conditions were conducted by employing the spectral element technique. As flow enters the vein from the graft, the velocity field exhibits flow separation and coherent structures (weak turbulence) that originate from the separation shear layer. We also report results of a porcine animal study in which the distribution and magnitude of vein-wall vibration on the venous anastomosis were measured at the time of graft construction. Preliminary molecular biology studies indicate elevated activity levels of the extracellular regulatory kinase ERK1/2, a mitogen-activated protein kinase involved in mechanotransduction, at regions of increased vein-wall vibration. These findings suggest a potential relationship between the associated turbulence-induced vein-wall vibration and the development of intimal hyperplasia in arteriovenous grafts. Further research is necessary, however, in order to determine if a correlation exists and to differentiate the vibration effect from that of flow related effects.


Subject(s)
Arteriovenous Anastomosis/physiopathology , Iliac Vein/physiopathology , Mitogen-Activated Protein Kinases/metabolism , Models, Cardiovascular , Animals , Aorta/metabolism , Aorta/pathology , Aorta/physiopathology , Aorta/surgery , Arteriovenous Anastomosis/metabolism , Arteriovenous Anastomosis/pathology , Blood Flow Velocity , Blood Vessel Prosthesis , Computer Simulation , Hemorheology/methods , Iliac Vein/metabolism , Iliac Vein/pathology , Iliac Vein/surgery , Mechanotransduction, Cellular , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3 , Shear Strength , Stress, Mechanical , Swine , Tissue Distribution , Veins/metabolism , Veins/pathology , Veins/physiopathology , Veins/surgery
13.
Radiographics ; 22(2): 283-94, 2002.
Article in English | MEDLINE | ID: mdl-11896219

ABSTRACT

In adnexal torsion, the ovary, ipsilateral fallopian tube, or both twist with the vascular pedicle, resulting in vascular compromise. Unrelieved torsion is likely to cause hemorrhagic infarction as the degree of arterial occlusion increases. Therefore, early diagnosis is important to preserve the affected ovary. Adnexal torsion commonly accompanies an ipsilateral ovarian neoplasm or cyst but can also occur in normal ovaries, usually in children. Although ultrasonography is typically the initial emergent examination, computed tomography (CT) and magnetic resonance (MR) imaging may also be useful diagnostic tools. Common CT and MR imaging features of adnexal torsion include fallopian tube thickening, smooth wall thickening of the twisted adnexal cystic mass, ascites, and uterine deviation to the twisted side. Uncommon imaging findings in adnexal torsion that are specific to hemorrhagic infarction include hemorrhage in the thickened fallopian tube, hemorrhage within the twisted ovarian mass, and hemoperitoneum. Additional imaging findings that can suggest hemorrhagic infarction include eccentric smooth wall thickening exceeding 10 mm in a cystic ovarian mass converging on the thickened fallopian tube and lack of contrast enhancement of the internal solid component or thickened wall of the twisted ovarian mass. Early diagnosis can help prevent irreversible structural damage and may allow conservative, ovary-sparing treatment.


Subject(s)
Adnexal Diseases/diagnosis , Magnetic Resonance Imaging , Tomography, X-Ray Computed , Adnexa Uteri/blood supply , Adnexal Diseases/diagnostic imaging , Adult , Female , Hemorrhage/diagnosis , Hemorrhage/diagnostic imaging , Humans , Infarction/diagnosis , Infarction/diagnostic imaging , Retrospective Studies , Torsion Abnormality/diagnosis , Torsion Abnormality/diagnostic imaging
14.
Blood ; 95(6): 2175-82, 2000 Mar 15.
Article in English | MEDLINE | ID: mdl-10706892

ABSTRACT

We describe a tolerance-based stem cell transplantation protocol that combines sublethal radiation with transient blockade of the CD40-CD154 costimulatory pathway using an anti-CD154 antibody. With this protocol, we established hematopoietic chimerism in BALB/c mice transplanted with fully allogeneic C57BL/6 bone marrow. The percentage of donor-origin mononuclear cells in recipients was more than 99%. In addition, all chimeric mice treated with anti-CD154 antibody remained free of graft-versus-host disease (GVHD) and accepted donor-origin but not third-party skin allografts. It was similarly possible to create allogeneic hematopoietic chimerism in NOD/Lt mice with spontaneous autoimmune diabetes. Pancreatic islet allografts transplanted into chimeric NOD/Lt mice were resistant not only to allorejection but also to recurrence of autoimmunity. We conclude that it is possible to establish robust allogeneic hematopoietic chimerism in sublethally irradiated mice without subsequent GVHD by blocking the CD40-CD154 costimulatory pathway using as few as 2 injections of anti-CD154 antibody. We also conclude that chimerism created in this way generates donor-specific allograft tolerance and reverses the predisposition to recurrent autoimmune diabetes in NOD/Lt mice, enabling them to accept curative islet allografts. (Blood. 2000;95:2175-2182)


Subject(s)
Autoimmunity , Bone Marrow/radiation effects , Graft Survival , Islets of Langerhans Transplantation , Membrane Glycoproteins/immunology , Transplantation Chimera , Transplantation, Homologous , Animals , CD40 Ligand , Diabetes Mellitus, Experimental/immunology , Diabetes Mellitus, Experimental/radiotherapy , Female , Graft vs Host Disease/prevention & control , Hyperglycemia/therapy , Immune Tolerance , Islets of Langerhans/anatomy & histology , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Inbred CBA , Mice, Inbred NOD , Recurrence , Skin Transplantation , Time Factors , Transplantation Conditioning/methods
15.
J Immunol ; 156(9): 3521-7, 1996 May 01.
Article in English | MEDLINE | ID: mdl-8617981

ABSTRACT

Cytokines have been shown to play an important role in regulating tolerance to islet Ags and provoking destructive islet lesions. However, data from a number of experimental systems have been conflicting, and the role of cytokines produced by T lymphocytes at various stages of diabetes has not been clearly defined. We have studied the production of cytokines in the pancreas during the development of autoimmune diabetes induced in mice by administration of (5) low doses of streptozotocin (STZ) (MDSDM). Diabetes in this model is T lymphocyte dependent. We used techniques of semiquantitative PCR to identify and quantitate cytokines that are produced. We have found that IL-2, IL-4, TNF-alpha, and IFN-gamma are expressed by the time the fourth dose of STZ is given. In the same pancreas, all of these cytokines (including IL-4) may be found. However, expression of IFN-gamma, but not IL-4, was limited to intrapancreatic lymphocytes and was not detectable at extrapancreatic lymphoid sites. Moreover, mAbs against IFN-gamma, but not against IL-4 or IL-2, prevent hyperglycemia and insulitis in MDSDM, suggesting that IFN-gamma regulates development of disease. Cells in the pancreases of nondiabetic mice treated with anti-IFN-gamma mAb and STZ show enhanced expression of IL-4, but the prevention of disease is due to blockade of the IFN-gamma itself, and not due to secretion of IL-4, because systemic administration of IL-4 does not prevent MDSDM. Thus, our findings indicate that cytokines produced by Th1 (or T cytolytic 1) and Th2 (or T cytolytic 2) cells are found in the pancreases of mice developing autoimmune diabetes. IFN-gamma is responsible for progression to diabetes, and its production is limited to lymphocytes only at that site.


Subject(s)
Autoimmune Diseases/chemically induced , Cytokines/biosynthesis , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/immunology , Streptozocin/toxicity , Animals , Antibodies, Monoclonal/therapeutic use , Autoimmune Diseases/metabolism , Autoimmune Diseases/therapy , Cytokines/genetics , Cytokines/immunology , Diabetes Mellitus, Experimental/metabolism , Dose-Response Relationship, Immunologic , Drug Administration Schedule , Injections, Intraperitoneal , Interferon-gamma/immunology , Interleukin-4/therapeutic use , Islets of Langerhans/cytology , Islets of Langerhans/metabolism , Lymphocytes/metabolism , Male , Mice , Mice, Inbred C57BL , Organ Specificity/immunology , Streptozocin/administration & dosage
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