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1.
Proc Natl Acad Sci U S A ; 120(3): e2218899120, 2023 01 17.
Article in English | MEDLINE | ID: mdl-36638211

ABSTRACT

Cleavage of the flavivirus premembrane (prM) structural protein during maturation can be inefficient. The contribution of partially mature flavivirus virions that retain uncleaved prM to pathogenesis during primary infection is unknown. To investigate this question, we characterized the functional properties of newly-generated dengue virus (DENV) prM-reactive monoclonal antibodies (mAbs) in vitro and using a mouse model of DENV disease. Anti-prM mAbs neutralized DENV infection in a virion maturation state-dependent manner. Alanine scanning mutagenesis and cryoelectron microscopy of anti-prM mAbs in complex with immature DENV defined two modes of attachment to a single antigenic site. In vivo, passive transfer of intact anti-prM mAbs resulted in an antibody-dependent enhancement of disease. However, protection against DENV-induced lethality was observed when the transferred mAbs were genetically modified to inhibit their ability to interact with Fcγ receptors. These data establish that in addition to mature forms of the virus, partially mature infectious prM+ virions can also contribute to pathogenesis during primary DENV infections.


Subject(s)
Antibodies, Monoclonal , Antibodies, Viral , Dengue Virus , Dengue , Cryoelectron Microscopy , Viral Envelope Proteins/metabolism , Virion/metabolism , Animals , Mice
2.
J Adolesc ; 94(2): 166-175, 2022 02.
Article in English | MEDLINE | ID: mdl-35353425

ABSTRACT

INTRODUCTION: Sacrificial moral dilemmas are a useful tool for understanding how individuals reconcile concerns for aggregate welfare with the emotional aversion to deliberately, personally harming others. Yet little is known about how adolescents respond to such dilemmas, even though adolescence is a crucial period for moral development. The present study sought to investigate how adolescents respond to such dilemmas, with a focus on gender differences, age differences, and the role of two individual differences factors: peer attachment and dampened interpersonal affect. METHODS: For this cross-sectional study, 103 adolescents (mean age = 14.5, SD = 0.81, range = 12-16; 54% girls; 41% Black, 24% White, 15% multiracial, 9% Hispanic/Latin, 3% Other, 2% Asian/Pacific Islander, 1% Native American, 5% no response) were recruited from the local community (Brooklyn, NY, USA). Adolescents responded to a series of sacrificial moral dilemmas. Then, participants and their caregivers completed questionnaires to assess adolescents' callous-unemotional traits (e.g., lack of empathy) and the quality of their peer relationships. RESULTS: On average, participants endorsed committing personal harm for the greater good in 53% of their responses. Girls endorsed personal utilitarian sacrifice more than boys. Peer attachment, but not dampened interpersonal affect, was associated with increased endorsement of personal utilitarian sacrifice. Age and responses to dilemmas were not associated. CONCLUSIONS: Our results suggest that peer relationships are an important part of adolescent moral decision-making, for girls in particular. Our results also indicate that adolescents' utilitarian responses to conventional sacrificial moral dilemmas do not reflect a decreased aversion to interpersonal harm.


Subject(s)
Decision Making , Men , Adolescent , Cross-Sectional Studies , Decision Making/physiology , Empathy , Female , Humans , Male , Morals
3.
Skeletal Radiol ; 50(5): 881-894, 2021 May.
Article in English | MEDLINE | ID: mdl-33095290

ABSTRACT

Shoulder arthroplasty is performed with increasing frequency, and osteoarthritis is the most common indication for this procedure. However, the glenoid side of the joint is widely recognized as a limiting factor in the long-term durability of shoulder replacement, and osteoarthritis leads to characteristic bony changes at the glenoid which can exacerbate this challenge by reducing the already limited glenoid bone stock, by altering biomechanics, and by interfering with operative exposure. This article reviews the Walch classification system for glenoid morphology. Several typical findings of osteoarthritis at the glenoid are discussed including central bone loss, posterior bone loss, retroversion, biconcavity, inclination, osteophyte formation, subchondral bone quality, and bone density. The three primary types of shoulder arthroplasty are reviewed, along with several techniques for addressing glenoid deformity, including eccentric reaming, bone grafting, and the use of augmented glenoid components. Ultimately, a primary objective at shoulder arthroplasty is to correct glenoid deformity while preserving bone stock, which depends critically on characterizing the glenoid at pre-operative imaging. Understanding the surgical techniques and the implications of glenoid morphology on surgical decision-making enables the radiologist to provide the morphologic information needed by the surgeon.


Subject(s)
Arthroplasty, Replacement, Shoulder , Glenoid Cavity , Osteoarthritis , Shoulder Joint , Surgeons , Glenoid Cavity/diagnostic imaging , Glenoid Cavity/surgery , Humans , Osteoarthritis/diagnostic imaging , Osteoarthritis/surgery , Shoulder Joint/diagnostic imaging , Shoulder Joint/surgery
4.
PLoS Pathog ; 11(11): e1005233, 2015.
Article in English | MEDLINE | ID: mdl-26539983

ABSTRACT

HIV reservoirs and production of viral antigens are not eliminated in chronically infected participants treated with combination antiretroviral therapy (cART). Novel therapeutic strategies aiming at viral reservoir elimination are needed to address chronic immune dysfunction and non-AIDS morbidities that exist despite effective cART. The HIV envelope protein (Env) is emerging as a highly specific viral target for therapeutic elimination of the persistent HIV-infected reservoirs via antibody-mediated cell killing. Dual-Affinity Re-Targeting (DART) molecules exhibit a distinct mechanism of action via binding the cell surface target antigen and simultaneously engaging CD3 on cytotoxic T lymphocytes (CTLs). We designed and evaluated Env-specific DARTs (HIVxCD3 DARTs) derived from known antibodies recognizing diverse Env epitopes with or without broadly neutralizing activity. HIVxCD3 DARTs derived from PGT121, PGT145, A32, and 7B2, but not VRC01 or 10E8 antibodies, mediated potent CTL-dependent killing of quiescent primary CD4 T cells infected with diverse HIV isolates. Similar killing activity was also observed with DARTs structurally modified for in vivo half-life extension. In an ex vivo model using cells isolated from HIV-infected participants on cART, combinations of the most potent HIVxCD3 DARTs reduced HIV expression both in quiescent and activated peripheral blood mononuclear cell cultures isolated from HIV-infected participants on suppressive cART. Importantly, HIVxCD3 DARTs did not induce cell-to-cell virus spread in resting or activated CD4 T cell cultures. Collectively, these results provide support for further development of HIVxCD3 DARTs as a promising therapeutic strategy for targeting HIV reservoirs.


Subject(s)
CD4-Positive T-Lymphocytes/virology , HIV Infections/immunology , HIV-1/drug effects , Leukocytes, Mononuclear/virology , T-Lymphocytes, Cytotoxic/virology , CD4 Antigens/immunology , CD4-Positive T-Lymphocytes/immunology , HIV Antibodies/immunology , HIV Antibodies/therapeutic use , HIV Infections/therapy , HIV-1/immunology , Humans , Leukocytes, Mononuclear/immunology , T-Lymphocytes, Cytotoxic/immunology
5.
Clin Immunol ; 149(3): 268-78, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23726024

ABSTRACT

Two humanized, anti-CD3 mAbs with reduced FcR binding, teplizumab and otelixizumab, have been evaluated in over 1500 subjects, ages 7-45, with new and recently diagnosed T1D with a range of intravenous doses (3-48mg) and regimens (6-14 days, single or repeat courses). In general, studies that used adequate dosing demonstrated improvement in stimulated C-peptide responses and reduced need for exogenous insulin for two years and even longer after diagnosis. Drug treatment causes a transient reduction in circulating T cells, but the available data suggest that the mechanism of action may involve induction of regulatory mechanisms. The adverse effects of anti-CD3 treatment are infusion-related and transient. The studies have identified significant differences in efficacy among patient groups suggesting that a key aspect for development of this immune therapy is identification of the demographic, metabolic, and immunologic features that distinguish subjects who are most likely to show beneficial clinical responses.


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , CD3 Complex/metabolism , Diabetes Mellitus, Type 1/drug therapy , Hypoglycemic Agents/therapeutic use , Adolescent , Adult , Age Factors , C-Peptide/metabolism , CD3 Complex/immunology , Child , Clinical Trials as Topic , Diabetes Mellitus, Type 1/immunology , Diabetes Mellitus, Type 1/metabolism , Diabetes Mellitus, Type 1/physiopathology , Female , Humans , Infusions, Intravenous , Insulin/metabolism , Male , Middle Aged , Receptors, Fc/immunology , Receptors, Fc/metabolism , T-Lymphocytes/drug effects , T-Lymphocytes/immunology , T-Lymphocytes/pathology
6.
Blood ; 117(17): 4542-51, 2011 Apr 28.
Article in English | MEDLINE | ID: mdl-21300981

ABSTRACT

We describe the application of a novel, bispecific antibody platform termed dual affinity retargeting (DART) to eradicate B-cell lymphoma through coengagement of the B cell-specific antigen CD19 and the TCR/CD3 complex on effector T cells. Comparison with a single-chain, bispecific antibody bearing identical CD19 and CD3 antibody Fv sequences revealed DART molecules to be more potent in directing B-cell lysis. The enhanced activity with the CD19xCD3 DART molecules was observed on all CD19-expressing target B cells evaluated using resting and prestimulated human PBMCs or purified effector T-cell populations. Characterization of a CD19xTCR bispecific DART molecule revealed equivalent potency with the CD19xCD3 DART molecule, demonstrating flexibility of the DART structure to support T-cell/B-cell associations for redirected T cell-killing applications. The enhanced level of killing mediated by DART molecules was not accompanied by any increase in nonspecific T-cell activation or lysis of CD19(-) cells. Cell-association studies indicated that the DART architecture is well suited for maintaining cell-to-cell contact, apparently contributing to the high level of target cell killing. Finally, the ability of the CD19xTCR DART to inhibit B-cell lymphoma in NOD/SCID mice when coadministered with human PBMCs supports further evaluation of DART molecules for the treatment of B-cell malignancies.


Subject(s)
Antibodies, Bispecific/immunology , Antibodies, Bispecific/pharmacology , B-Lymphocytes/immunology , Lymphoma, B-Cell , T-Lymphocytes/immunology , Animals , Antigens, CD19/immunology , Antigens, CD19/metabolism , B-Lymphocytes/cytology , CD3 Complex/immunology , CD3 Complex/metabolism , Cell Communication/immunology , Cell Line, Tumor , Female , Humans , Lymphokines/immunology , Lymphoma, B-Cell/drug therapy , Lymphoma, B-Cell/immunology , Lymphoma, B-Cell/pathology , Mice , Mice, Inbred NOD , Mice, SCID , Receptors, Antigen, T-Cell/immunology , Receptors, Antigen, T-Cell/metabolism , Sialoglycoproteins/immunology , T-Lymphocytes/cytology , Xenograft Model Antitumor Assays
7.
J Knee Surg ; 36(3): 305-309, 2023 Feb.
Article in English | MEDLINE | ID: mdl-34474493

ABSTRACT

MRI is an essential diagnostic imaging modality for many knee conditions; however, it is not indicated in the setting of advanced knee arthritis. Inappropriate MRI imaging adds to health care costs and may delay definitive management for many patients. The primary purpose of this study was to ascertain the frequency of inappropriate MRI scans performed at one Veterans' Administration Medical Center (VAMC). We performed a retrospective chart review of all knee MRIs ordered over a 6-month period. Inappropriate MRI was defined as MRI performed prior to radiographs (XRs), or in the presence of XRs demonstrating severe osteoarthritis, without leading to a nonarthroplasty procedure of the knee. Of the 304 cases reviewed, 36.8% (112) of the MRIs were deemed inappropriate, 33 were ordered by orthopedists, and 79 were ordered by other health care providers. Of the 33 ordered by orthopedists, 25 were ordered by retired/nonsurgical orthopedists. Obtaining an MRI delayed care by an average of 29.2 days. Of the 252 cases that had XR prior to MRI, none included all four views in the standard knee XR series and only four had weightbearing images. Over a third of knee MRIs performed at this VAMC were inappropriate and delayed care. Additionally, no XRs in our study contained all the necessary views to properly assess knee arthritis. These concerning findings signify a potential opportunity for education in diagnostic strategies, to better patient care and resource utilization in the VAMC.


Subject(s)
Osteoarthritis , Veterans , Humans , Retrospective Studies , Pain , Magnetic Resonance Imaging
8.
J Exp Med ; 203(9): 2157-64, 2006 Sep 04.
Article in English | MEDLINE | ID: mdl-16923849

ABSTRACT

The inappropriate expansion and activation of autoreactive memory B cells and plasmablasts contributes to loss of self-tolerance in systemic lupus erythematosus (SLE). Defects in the inhibitory Fc receptor, FcgammaRIIB, have been shown to contribute to B cell activation and autoimmunity in several mouse models of SLE. In this paper, we demonstrate that expression of FcgammaRIIB is routinely up-regulated on memory B cells in the peripheral blood of healthy controls, whereas up-regulation of FcgammaRIIB is considerably decreased in memory B cells of SLE patients. This directly correlates with decreased FcgammaRIIB-mediated suppression of B cell receptor-induced calcium (Ca2+) response in those B cells. We also found substantial overrepresentation of African-American patients among those who failed to up-regulate FcgammaRIIB. These results suggest that the inhibitory receptor, FcgammaRIIB, may be impaired at a critical checkpoint in SLE in the regulation of memory B cells; thus, FcgammaRIIB represents a novel target for therapeutic interventions in this disease.


Subject(s)
B-Lymphocyte Subsets/immunology , Immunologic Memory , Lupus Erythematosus, Systemic/immunology , Receptors, IgG/metabolism , Adult , Black or African American , Animals , B-Lymphocyte Subsets/cytology , B-Lymphocyte Subsets/physiology , Calcium/metabolism , Female , Humans , Lymphocyte Activation , Male , Mice , Middle Aged , Receptors, Antigen, B-Cell/immunology
9.
Lancet ; 378(9790): 487-97, 2011 Aug 06.
Article in English | MEDLINE | ID: mdl-21719095

ABSTRACT

BACKGROUND: Findings of small studies have suggested that short treatments with anti-CD3 monoclonal antibodies that are mutated to reduce Fc receptor binding preserve ß-cell function and decrease insulin needs in patients with recent-onset type 1 diabetes. In this phase 3 trial, we assessed the safety and efficacy of one such antibody, teplizumab. METHODS: In this 2-year trial, patients aged 8-35 years who had been diagnosed with type 1 diabetes for 12 weeks or fewer were enrolled and treated at 83 clinical centres in North America, Europe, Israel, and India. Participants were allocated (2:1:1:1 ratio) by an interactive telephone system, according to computer-generated block randomisation, to receive one of three regimens of teplizumab infusions (14-day full dose, 14-day low dose, or 6-day full dose) or placebo at baseline and at 26 weeks. The Protégé study is still underway, and patients and study staff remain masked through to study closure. The primary composite outcome was the percentage of patients with insulin use of less than 0·5 U/kg per day and glycated haemoglobin A(1c) (HbA(1C)) of less than 6·5% at 1 year. Analyses included all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT00385697. FINDINGS: 763 patients were screened, of whom 516 were randomised to receive 14-day full-dose teplizumab (n=209), 14-day low-dose teplizumab (n=102), 6-day full-dose teplizumab (n=106), or placebo (n=99). Two patients in the 14-day full-dose group and one patient in the placebo group did not start treatment, so 513 patients were eligible for efficacy analyses. The primary outcome did not differ between groups at 1 year: 19·8% (41/207) in the 14-day full-dose group; 13·7% (14/102) in the 14-day low-dose group; 20·8% (22/106) in the 6-day full-dose group; and 20·4% (20/98) in the placebo group. 5% (19/415) of patients in the teplizumab groups were not taking insulin at 1 year, compared with no patients in the placebo group at 1 year (p=0·03). Across the four study groups, similar proportions of patients had adverse events (414/417 [99%] in the teplizumab groups vs 98/99 [99%] in the placebo group) and serious adverse events (42/417 [10%] vs 9/99 [9%]). The most common clinical adverse event in the teplizumab groups was rash (220/417 [53%] vs 20/99 [20%] in the placebo group). INTERPRETATION: Findings of exploratory analyses suggest that future studies of immunotherapeutic intervention with teplizumab might have increased success in prevention of a decline in ß-cell function (measured by C-peptide) and provision of glycaemic control at reduced doses of insulin if they target patients early after diagnosis of diabetes and children. FUNDING: MacroGenics, the Juvenile Diabetes Research Foundation, and Eli Lilly.


Subject(s)
CD3 Complex/drug effects , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 1/immunology , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use , Muromonab-CD3/therapeutic use , Adolescent , Adult , Antibodies, Monoclonal, Humanized , C-Peptide/blood , CD3 Complex/immunology , Canada , Child , Diabetes Mellitus, Type 1/blood , Drug Administration Schedule , Drug Eruptions/etiology , Europe , Female , Glycated Hemoglobin/metabolism , Humans , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/adverse effects , Hypoglycemic Agents/immunology , India , Insulin/administration & dosage , Insulin-Secreting Cells/drug effects , Insulin-Secreting Cells/immunology , Israel , Male , Mexico , Muromonab-CD3/administration & dosage , Muromonab-CD3/adverse effects , Muromonab-CD3/immunology , Treatment Outcome , United States , Young Adult
10.
J Knee Surg ; 35(5): 521-528, 2022 Apr.
Article in English | MEDLINE | ID: mdl-32898902

ABSTRACT

The purpose of this study was to evaluate Patient-Reported Outcomes Measurement Information System physical function (PROMIS PF) 2 years following knee surgery, and identify preoperative factors associated with postoperative PROMIS PF. Three hundred and sixty-five patients, age 17 years and older, undergoing knee surgery at one institution were studied. Patients completed multiple questionnaires prior to surgery and again 2 years postoperatively including PROMIS PF, International Knee Documentation Committee (IKDC), joint and body numeric pain scales (NPS), Tegner's activity scale (TAS), and Marx's activity rating scale (MARS). Mean PROMIS PF improved from 41.4 to 50.9 at 2 years postoperatively (p < 0.001) and was strongly correlated with 2-year IKDC scores. Older age, female gender, non-Hispanic ethnicity, unemployment, lower income, government insurance, smoking, preoperative opioid use, having a legal claim, comorbidities, previous surgeries, higher body mass index (BMI), and knee arthroplasty were associated with worse 2-year PROMIS PF. Multivariable analysis confirmed that lower BMI, less NPS body pain, and higher MARS were independent predictors of greater 2-year PROMIS PF and better improvement in PROMIS PF. In this large, broad cohort of knee surgery patients, multiple preoperative factors were associated with PROMIS PF 2 years postoperatively. PROMIS PF scores improved significantly, but worse 2 year PROMIS PF scores and less improvement from baseline were independently predicted by higher BMI, greater NPS body pain, and lower MARS activity level. PROMIS PF can be implemented as an efficient means to assess outcomes after knee surgery.


Subject(s)
Orthopedic Procedures , Patient Reported Outcome Measures , Adolescent , Female , Humans , Knee/surgery , Knee Joint/surgery , Pain
11.
Mol Cancer Ther ; 21(7): 1047-1059, 2022 07 05.
Article in English | MEDLINE | ID: mdl-35511740

ABSTRACT

ADAM metallopeptidase domain 9 (ADAM9) is a member of the ADAM family of multifunctional, multidomain type 1 transmembrane proteins. ADAM9 is overexpressed in many cancers, including non-small cell lung, pancreatic, gastric, breast, ovarian, and colorectal cancer, but exhibits limited expression in normal tissues. A target-unbiased discovery platform based on intact tumor and progenitor cell immunizations, followed by an IHC screen, led to the identification of anti-ADAM9 antibodies with selective tumor-versus-normal tissue binding. Subsequent analysis revealed anti-ADAM9 antibodies were efficiently internalized and processed by tumor cells making ADAM9 an attractive target for antibody-drug conjugate (ADC) development. Here, we describe the preclinical evaluation of IMGC936, a novel ADC targeted against ADAM9. IMGC936 is comprised of a high-affinity humanized antibody site-specifically conjugated to DM21-C, a next-generation linker-payload that combines a maytansinoid microtubule-disrupting payload with a stable tripeptide linker, at a drug antibody ratio of approximately 2.0. In addition, the YTE mutation (M252Y/S254T/T256E) was introduced into the CH2 domain of the antibody Fc to maximize in vivo plasma half-life and exposure. IMGC936 exhibited cytotoxicity toward ADAM9-positive human tumor cell lines, as well as bystander killing, potent antitumor activity in human cell line-derived xenograft and patient-derived xenograft tumor models, and an acceptable safety profile in cynomolgus monkeys with favorable pharmacokinetic properties. Our preclinical data provide a strong scientific rationale for the further development of IMGC936 as a therapeutic candidate for the treatment of ADAM9-positive cancers. A first-in-human study of IMGC936 in patients with advanced solid tumors has been initiated (NCT04622774).


Subject(s)
Immunoconjugates , ADAM Proteins , Cell Line, Tumor , Heterografts , Humans , Immunoconjugates/chemistry , Membrane Proteins/genetics , Xenograft Model Antitumor Assays
12.
Breast Cancer Res ; 13(6): R123, 2011.
Article in English | MEDLINE | ID: mdl-22129105

ABSTRACT

INTRODUCTION: Response to trastuzumab in metastatic breast cancer correlates with expression of the high binding variant (158V) of the activating Fcγ receptor IIIA (CD16A). We engineered MGAH22, a chimeric anti-HER2 monoclonal antibody with specificity and affinity similar to trastuzumab, with an Fc domain engineered for increased binding to both alleles of human CD16A. METHODS: MGAH22 was compared to an identical anti-HER2 mAb except for a wild type Fc domain. Antibody-dependent cell cytotoxicity (ADCC) assays were performed with HER2-expressing cancer cells as targets and human PBMC or purified NK cells as effectors. Xenograft studies were conducted in mice with wild type murine FcγRs; in mice lacking murine CD16; or in mice lacking murine CD16 but transgenic for human CD16A-158F, the low-binding variant. The latter model reproduces the differential binding between wild type and the Fc-optimized mAb for human CD16A. The JIMT-1 human breast tumor line, derived from a patient that progressed on trastuzumab therapy, was used in these studies. Single and repeat dose toxicology studies with MGAH22 administered intravenously at high dose were conducted in cynomolgus monkeys. RESULTS: The optimized Fc domain confers enhanced ADCC against all HER2-positive tumor cells tested, including cells resistant to trastuzumab's anti-proliferative activity or expressing low HER2 levels. The greatest improvement occurs with effector cells isolated from donors homozygous or heterozygous for CD16A-158F, the low-binding allele. MGAH22 demonstrates increased activity against HER2-expressing tumors in mice transgenic for human CD16A-158F. In single and repeat-dose toxicology studies in cynomolgus monkeys, a species with a HER2 expression pattern comparable to that in humans and Fcγ receptors that exhibit enhanced binding to the optimized Fc domain, MGAH22 was well tolerated at all doses tested (15-150 mg/kg) and exhibited pharmacokinetic parameters similar to that of other anti-HER2 antibodies. Induction of cytokine release by MGAH22 in vivo or in vitro was similar to that induced by the corresponding wild type mAb or trastuzumab. CONCLUSIONS: The data support the clinical development of MGAH22, which may have utility in patients with low HER2 expressing tumors or carrying the CD16A low-binding allele.


Subject(s)
Antibodies, Monoclonal/pharmacology , Antineoplastic Agents/pharmacology , Receptor, ErbB-2/antagonists & inhibitors , Receptors, IgG/metabolism , Animals , Antibodies, Monoclonal/metabolism , Antibodies, Monoclonal/toxicity , Antibodies, Monoclonal, Humanized/pharmacology , Antibody-Dependent Cell Cytotoxicity , Antineoplastic Agents/metabolism , Antineoplastic Agents/toxicity , Cell Line, Tumor , Cell Proliferation/drug effects , Female , Humans , Macaca fascicularis , Male , Mice , Mice, Inbred BALB C , Mice, Transgenic , Neoplasms/metabolism , Protein Binding , Receptor, ErbB-2/immunology , Receptor, ErbB-2/metabolism , Trastuzumab
13.
Arthritis Rheum ; 62(7): 1933-43, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20506263

ABSTRACT

OBJECTIVE: To exploit the physiologic Fcgamma receptor IIb (CD32B) inhibitory coupling mechanism to control B cell activation by constructing a novel bispecific diabody scaffold, termed a dual-affinity retargeting (DART) molecule, for therapeutic applications. METHODS: DART molecules were constructed by pairing an Fv region from a monoclonal antibody (mAb) directed against CD32B with an Fv region from a mAb directed against CD79B, the beta-chain of the invariant signal-transducing dimer of the B cell receptor complex. DART molecules were characterized physicochemically and for their ability to simultaneously bind the target receptors in vitro and in intact cells. The ability of the DART molecules to negatively control B cell activation was determined by calcium mobilization, by tyrosine phosphorylation of signaling molecules, and by proliferation and Ig secretion assays. A DART molecule specific for the mouse ortholog of CD32B and CD79B was also constructed and tested for its ability to inhibit B cell proliferation in vitro and to control disease severity in a collagen-induced arthritis (CIA) model. RESULTS: DART molecules were able to specifically bind and coligate their target molecules on the surface of B cells and demonstrated a preferential simultaneous binding to both receptors on the same cell. DART molecules triggered the CD32B-mediated inhibitory signaling pathway in activated B cells, which translated into inhibition of B cell proliferation and Ig secretion. A DART molecule directed against the mouse orthologs was effective in inhibiting the development of CIA in DBA/1 mice. CONCLUSION: This innovative bispecific antibody scaffold that simultaneously engages activating and inhibitory receptors enables novel therapeutic approaches for the treatment of rheumatoid arthritis and potentially other autoimmune and inflammatory diseases in humans.


Subject(s)
Antibodies, Bispecific/pharmacology , Antibodies, Monoclonal/pharmacology , B-Lymphocytes/drug effects , Immunosuppressive Agents/pharmacology , Lymphocyte Activation/drug effects , Receptors, IgG , Animals , Antibodies, Bispecific/immunology , Antibodies, Bispecific/pharmacokinetics , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/pharmacokinetics , Antigen-Antibody Complex/immunology , Antigen-Antibody Complex/metabolism , Arthritis, Experimental/drug therapy , Arthritis, Experimental/immunology , B-Lymphocytes/cytology , B-Lymphocytes/immunology , CD79 Antigens/immunology , Cell Proliferation/drug effects , Cells, Cultured , Dimerization , Female , Humans , Immunoglobulins/metabolism , Immunosuppressive Agents/immunology , Immunosuppressive Agents/pharmacokinetics , Lymphocyte Activation/immunology , Male , Mice , Mice, Knockout , Receptors, IgG/immunology , Signal Transduction , Spleen/cytology , Tissue Scaffolds
14.
J Immunol ; 183(7): 4509-20, 2009 Oct 01.
Article in English | MEDLINE | ID: mdl-19734236

ABSTRACT

Rheumatoid arthritis (RA) is a common autoimmune disease leading to profound disability and premature death. Although a role for FcgammaRs and TLRs is accepted, their precise involvement remains to be elucidated. FcgammaRIIb is an inhibitory FcR important in the maintenance of tolerance. We hypothesized that the inhibitory FcgammaRIIb inhibits TLR responses on monocyte-derived dendritic cells (DC) and serves as a counterregulatory mechanism to dampen inflammation, and we surmised that this mechanism might be defective in RA. The expression of the inhibitory FcgammaRIIb was found to be significantly higher on DCs from RA patients having low RA disease activity in the absence of treatment with antirheumatic drugs. The expression of activating FcgammaRs was similarly distributed among all RA patients and healthy controls. Intriguingly, only DCs with a high expression of FcgammaRIIb were able to inhibit TLR4-mediated secretion of proinflammatory cytokines when stimulated with immune complexes. In addition, when these DCs were coincubated with the combination of a TLR4 agonist and immune complexes, a markedly inhibited T cell proliferation was apparent, regulatory T cell development was promoted, and T cells were primed to produce high levels of IL-13 compared with stimulation of the DCs with the TLR4 agonist alone. Blocking FcgammaRIIb with specific Abs fully abrogated these effects demonstrating the full dependence on the inhibitory FcgammaRIIb in the induction of these phenomena. This TLR4-FcgammaRIIb interaction was shown to dependent on the PI3K and Akt pathway.


Subject(s)
Arthritis, Rheumatoid/immunology , Dendritic Cells/immunology , Down-Regulation/immunology , Growth Inhibitors/physiology , Receptors, IgG/physiology , Toll-Like Receptor 4/antagonists & inhibitors , Toll-Like Receptor 4/physiology , Up-Regulation/immunology , Aged , Antigen-Antibody Complex/physiology , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/metabolism , Cells, Cultured , Cohort Studies , Cytokines/metabolism , Dendritic Cells/metabolism , Dendritic Cells/pathology , Down-Regulation/genetics , Growth Inhibitors/biosynthesis , Growth Inhibitors/genetics , Humans , Inflammation Mediators/metabolism , Lymphocyte Activation/genetics , Lymphocyte Activation/immunology , Prospective Studies , Receptors, IgG/biosynthesis , Receptors, IgG/genetics , Up-Regulation/genetics
15.
Arthroplast Today ; 8: 128-131, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33748372

ABSTRACT

Revision total knee arthroplasty often necessitates removing well-fixed components. Tibial tray removal is challenging becaue of 1) physical barriers posed by the component pegs, keel, or stem in accessing the implant-bone interface circumferentially and 2) proximity of vulnerable structures including the patellar tendon, collateral ligaments, popliteal artery, and distal femur. In this report, we present a step-by-step technique for removal of a well-fixed tibial component using a single-sided reciprocating saw.

16.
J Orthop ; 25: 88-92, 2021.
Article in English | MEDLINE | ID: mdl-33994704

ABSTRACT

For septic arthritis of the knee, we attempted to determine: the preferred surgical technique in the United-States (US), the believed "gold-standard" treatment among others. This was performed by an electronic-survey distributed to all academic orthopaedic faculty throughout the US. The preferred method was arthroscopy (69.8%). Arthroscopy is believed to be the gold-standard in 27.0%, arthrotomy in 29.4%, while 43.5% believe no gold-standard exists. In conclusion the majority of surgeons prefer arthroscopy when managing a native, septic knee in an adult patient. However, there is no national consensus on a gold-standard treatment or the role of synovectomy.

17.
J Clin Orthop Trauma ; 20: 101486, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34277340

ABSTRACT

BACKGROUND: Patient satisfaction metrics are increasingly being utilized as tools to evaluate the quality of healthcare and affect reimbursements. The objectives of this study were to (1) identify factors associated with two-year patient satisfaction after elective knee surgery, (2) compare the Surgical Satisfaction Questionnaire-8 (SSQ-8) and a numeric satisfaction scale (NSS), and (3) determine if two-year patient satisfaction can be predicted based on preoperative factors. METHODS: A total of 365 patients undergoing elective knee surgery at a single center were administered questionnaires to assess demographics, medical history, and various patient-reported outcomes preoperatively and at two years postoperatively. Patient satisfaction was measured at two years postoperatively with SSQ-8 and NSS. Bivariate and multivariate statistical analyses were performed to identify significant associations and independent predictors of satisfaction. RESULTS: SSQ-8 and NSS scores were significantly correlated (rs = 0.68, P < 0.0001). Lower SSQ-8 and NSS scores were associated with black race, higher BMI, more comorbidities, unemployment, smoking, higher ASA score, and greater Met Expectations (P < 0.05). Better scores on patient-based outcome measures and better improvement from baseline were significantly correlated with higher satisfaction on both SSQ-8 and NSS. Multivariable analysis identified greater Met Expectations and higher two-year Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Interference scores as independent predictors of greater SSQ-8 scores (adjusted r2 = .52). Greater Met Expectations and better two-year PROMIS Social Satisfaction scores were independent predictors of NSS score (adjusted r2 = .41). In contrast, when only preoperative variables were considered, the multivariable regression model accounted for only 14% of the variance in SSQ-8 and 6% of the variance in NSS. CONCLUSION: While there are multiple preoperative factors that are associated with two-year patient satisfaction after knee surgery, those factors contribute relatively little to satisfaction. Meeting expectations and better patient-based outcomes at two years are more important.

18.
JAMA Oncol ; 7(4): 573-584, 2021 Apr 01.
Article in English | MEDLINE | ID: mdl-33480963

ABSTRACT

IMPORTANCE: ERRB2 (formerly HER2)-positive advanced breast cancer (ABC) remains typically incurable with optimal treatment undefined in later lines of therapy. The chimeric antibody margetuximab shares ERBB2 specificity with trastuzumab but incorporates an engineered Fc region to increase immune activation. OBJECTIVE: To compare the clinical efficacy of margetuximab vs trastuzumab, each with chemotherapy, in patients with pretreated ERBB2-positive ABC. DESIGN, SETTING, AND PARTICIPANTS: The SOPHIA phase 3 randomized open-label trial of margetuximab plus chemotherapy vs trastuzumab plus chemotherapy enrolled 536 patients from August 26, 2015, to October 10, 2018, at 166 sites in 17 countries. Eligible patients had disease progression on 2 or more prior anti-ERBB2 therapies and 1 to 3 lines of therapy for metastatic disease. Data were analyzed from February 2019 to October 2019. INTERVENTIONS: Investigators selected chemotherapy before 1:1 randomization to margetuximab, 15 mg/kg, or trastuzumab, 6 mg/kg (loading dose, 8 mg/kg), each in 3-week cycles. Stratification factors were metastatic sites (≤2, >2), lines of therapy (≤2, >2), and chemotherapy choice. MAIN OUTCOMES AND MEASURES: Sequential primary end points were progression-free survival (PFS) by central blinded analysis and overall survival (OS). All α was allocated to PFS, followed by OS. Secondary end points were investigator-assessed PFS and objective response rate by central blinded analysis. RESULTS: A total of 536 patients were randomized to receive margetuximab (n = 266) or trastuzumab (n = 270). The median age was 56 (27-86) years; 266 (100%) women were in the margetuximab group, while 267 (98.9%) women were in the trastuzumab group. Groups were balanced. All but 1 patient had received prior pertuzumab, and 489 (91.2%) had received prior ado-trastuzumab emtansine. Margetuximab improved primary PFS over trastuzumab with 24% relative risk reduction (hazard ratio [HR], 0.76; 95% CI, 0.59-0.98; P = .03; median, 5.8 [95% CI, 5.5-7.0] months vs 4.9 [95% CI, 4.2-5.6] months; October 10, 2018). After the second planned interim analysis of 270 deaths, median OS was 21.6 months with margetuximab vs 19.8 months with trastuzumab (HR, 0.89; 95% CI, 0.69-1.13; P = .33; September 10, 2019), and investigator-assessed PFS showed 29% relative risk reduction favoring margetuximab (HR, 0.71; 95% CI, 0.58-0.86; P < .001; median, 5.7 vs 4.4 months; September 10, 2019). Margetuximab improved objective response rate over trastuzumab: 22% vs 16% (P = .06; October 10, 2018), and 25% vs 14% (P < .001; September 10, 2019). Incidence of infusion-related reactions, mostly in cycle 1, was higher with margetuximab (35 [13.3%] vs 9 [3.4%]); otherwise, safety was comparable. CONCLUSIONS AND RELEVANCE: In this phase 3 randomized clinical trial, margetuximab plus chemotherapy had acceptable safety and a statistically significant improvement in PFS compared with trastuzumab plus chemotherapy in ERBB2-positive ABC after progression on 2 or more prior anti-ERBB2 therapies. Final OS analysis is expected in 2021. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02492711.


Subject(s)
Antibodies, Monoclonal , Breast Neoplasms , Trastuzumab , Ado-Trastuzumab Emtansine , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal/therapeutic use , Antineoplastic Combined Chemotherapy Protocols , Breast Neoplasms/drug therapy , Female , Humans , Middle Aged , Receptor, ErbB-2/analysis , Trastuzumab/adverse effects , Trastuzumab/therapeutic use
19.
Antimicrob Agents Chemother ; 54(6): 2431-6, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20350945

ABSTRACT

West Nile Virus (WNV) is a neurotropic flavivirus that can cause debilitating diseases, such as encephalitis, meningitis, or flaccid paralysis. We report the safety, pharmacokinetics, and immunogenicity of a recombinant humanized monoclonal antibody (MGAWN1) targeting the E protein of WNV in a phase 1 study, the first to be performed on humans. A single intravenous infusion of saline or of MGAWN1 at escalating doses (0.3, 1, 3, 10, or 30 mg/kg of body weight) was administered to 40 healthy volunteers (30 receiving MGAWN1; 10 receiving placebo). Subjects were evaluated on days 0, 1, 3, 7, 14, 21, 28, 42, 56, 91, 120, and 180 by clinical assessments, clinical laboratory studies, electrocardiograms (ECGs), and pharmacokinetic and immunogenicity assays. All 40 subjects tolerated the infusion of the study drug, and 39 subjects completed the study. One serious adverse event of schizophrenia occurred in the 0.3-mg/kg cohort. One grade 3 neutropenia occurred in the 3-mg/kg cohort. Six MGAWN1-treated subjects experienced 11 drug-related adverse events, including diarrhea (1 subject), chest discomfort (1), oral herpes (1), rhinitis (1), neutropenia (2), leukopenia (1), dizziness (1), headache (2), and somnolence (1). In the 30-mg/kg cohort, MGAWN1 had a half-life of 26.7 days and a maximum concentration in serum (C(max)) of 953 microg/ml. This study suggests that single infusions of MGAWN1 up to 30 mg/kg appear to be safe and well tolerated in healthy subjects. The C(max) of 953 microg/ml exceeds the target level in serum estimated from hamster studies by 28-fold and should provide excess WNV neutralizing activity and penetration into the brain and cerebrospinal fluid (CSF). Further evaluation of MGAWN1 for the treatment of West Nile virus infections is warranted.


Subject(s)
Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal/pharmacokinetics , Antibodies, Viral/adverse effects , West Nile virus/immunology , Adult , Animals , Antibodies, Anti-Idiotypic/biosynthesis , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/administration & dosage , Antibodies, Neutralizing/adverse effects , Antibodies, Neutralizing/blood , Antibodies, Neutralizing/immunology , Antibodies, Viral/administration & dosage , Antibodies, Viral/blood , Antibodies, Viral/immunology , Cricetinae , Double-Blind Method , Female , Humans , Infusions, Intravenous , Male , Middle Aged , Neutropenia/etiology , Recombinant Proteins/administration & dosage , Recombinant Proteins/adverse effects , Recombinant Proteins/immunology , Recombinant Proteins/pharmacokinetics , West Nile Fever/therapy , Young Adult
20.
J Health Care Finance ; 37(1): 30-4, 2010.
Article in English | MEDLINE | ID: mdl-20973371

ABSTRACT

The antidote for a healthy bottom line is a streamlined payment recovery process from self-pay patients. Due to the current high unemployment rate and a resulting spike in self-pay patients, CFOs must be proactive and identify self-pay debt recovery solutions to stay in the black. It is vital to design an effective and efficient process that works for the specific needs of the hospital or practice. Utilizing metrics, reconditioning patients to pay at point-of-service, training associates to appropriately request payment, and understanding the limitations of the business office are key elements to financial health. Identifying an accounts receivable management partner could significantly reduce headaches and strain on staff and time.


Subject(s)
Economics, Hospital , Financing, Personal , Patient Credit and Collection/organization & administration , Humans , Outsourced Services , Patient Satisfaction , United States
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