Varenicline for Tobacco-Dependent Adults Who Are Not Ready to Discontinue Use: A Systematic Review and Meta-Analysis.

Rationale: Not all individuals with tobacco dependence are ready to give up smoking. Research reveals behavioral differences between adults ready to discontinue tobacco use and those who are not. Thus, the interventions applied to these populations might differ. However, the evidence of using varenicline in individuals who are not ready to discontinue tobacco use is uncertain. Objectives: To determine if, in tobacco-dependent adults who report not being ready to discontinue tobacco use, clinicians should begin treatment with varenicline or wait until subjects are ready to discontinue tobacco use. Methods: We conducted a systematic review to assess the effectiveness and safety of treatment with varenicline in tobacco-dependent adults who are not ready to discontinue tobacco use. We systematically searched the Cumulative Index to Nursing and Allied Health Literature, Embase, MEDLINE, and the Cochrane Central Register of Controlled Trials to identify randomized controlled trials comparing varenicline versus placebo for individuals who were not ready to discontinue tobacco use. Outcomes of interest include point prevalence abstinence during treatment or at six months or longer, smoking reduction, motivation to quit, adverse events, and withdrawal symptoms. Two authors independently extracted data and assessed eligibility and risk of bias using a standardized data collection form. We followed the Grading of Recommendations, Assessment, Development and Evaluations approach to assess the certainty of evidence. Results: Five trials met our inclusion criteria. All 2,616 participants were adults who were not ready to discontinue tobacco use at study entry. For 7-day point prevalence abstinence at six months or longer, high-certainty evidence suggested that varenicline increased abstinence compared with placebo (relative risk, 2.00 [95% confidence interval (CI), 1.70-2.35]; absolute risk reduction, 173 more per 1,000 [95% CI, 121 more to 234 more]). We identified moderate-certainty evidence suggesting that varenicline increased serious adverse events (relative risk, 1.75 [95% CI, 0.98-3.13]; absolute risk reduction, 12 more per 1,000 [95% CI, 0 fewer to 35 more]). For withdrawal, low-certainty evidence suggested that varenicline treatment was associated with a lower symptom score (mean difference, 1.54 points lower; 95% CI, 2.15-0.93 points lower; low certainty) assessed using the Brief Questionnaire of Smoking Urges. Conclusions: In tobacco-dependent adults who are not ready to discontinue tobacco use, initiating varenicline treatment results in a large increase in abstinence and likely results in a slight increase in serious adverse events.

Leveraging the antiviral type I interferon system as a first line of defense against SARS-CoV-2 pathogenicity.

The emergence and spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in significant global morbidity, mortality, and societal disruption. A better understanding of virus-host interactions may potentiate therapeutic insights toward limiting this infection. Here we investigated the dynamics of the systemic response to SARS-CoV-2 in hamsters by histological analysis and transcriptional profiling. Infection resulted in consistently high levels of virus in the upper and lower respiratory tracts and sporadic occurrence in other distal tissues. A longitudinal cohort revealed a wave of inflammation, including a type I interferon (IFN-I) response, that was evident in all tissues regardless of viral presence but was insufficient to prevent disease progression. Bolstering the antiviral response with intranasal administration of recombinant IFN-I reduced viral disease, prevented transmission, and lowered inflammation in vivo. This study defines the systemic host response to SARS-CoV-2 infection and supports use of intranasal IFN-I as an effective means of early treatment.

Cutaneous leukocyte lineages in tolerant large animal and immunosuppressed clinical vascularized composite allograft recipients.

Vascularized composite allografts (VCAs) can restore fully functional anatomic units in patients with limb amputations or severe facial tissue loss. However, acute rejection of the skin is frequently observed and underscores the importance of developing tolerance induction protocols. In this study, we have characterized the skin immune system in VCAs. We demonstrate infiltration of recipient leukocytes, regardless of rejection status, and in tolerant mixed hematopoietic chimeras, the co-existence of these cells with donor leukocytes in the absence of rejection. Here we characterize the dermal T cell and epidermal Langerhans cell components of the skin immune system in our porcine model of VCA tolerance, and the kinetics of cutaneous chimerism in both of these populations in VCAs transplanted to tolerant and nontolerant recipients, as well as in host skin. Furthermore, in biopsies from the first patient to receive a hand transplant in our program, we demonstrate the presence of recipient T cells in the skin of the transplanted limb in the absence of clinical or histological evidence of rejection.

Genome-wide transposon mutagenesis of paramyxoviruses reveals constraints on genomic plasticity.

The antigenic and genomic stability of paramyxoviruses remains a mystery. Here, we evaluate the genetic plasticity of Sendai virus (SeV) and mumps virus (MuV), sialic acid-using paramyxoviruses that infect mammals from two Paramyxoviridae subfamilies (Orthoparamyxovirinae and Rubulavirinae). We performed saturating whole-genome transposon insertional mutagenesis, and identified important commonalities: disordered regions in the N and P genes near the 3' genomic end were more tolerant to insertional disruptions; but the envelope glycoproteins were not, highlighting structural constraints that contribute to the restricted antigenic drift in paramyxoviruses. Nonetheless, when we applied our strategy to a fusion-defective Newcastle disease virus (Avulavirinae subfamily), we could select for F-revertants and other insertants in the 5' end of the genome. Our genome-wide interrogation of representative paramyxovirus genomes from all three Paramyxoviridae subfamilies provides a family-wide context in which to explore specific variations within and among paramyxovirus genera and species.

Initiating Pharmacologic Treatment in Tobacco-Dependent Adults. An Official American Thoracic Society Clinical Practice Guideline.

Background: Current tobacco treatment guidelines have established the efficacy of available interventions, but they do not provide detailed guidance for common implementation questions frequently faced in the clinic. An evidence-based guideline was created that addresses several pharmacotherapy-initiation questions that routinely confront treatment teams.Methods: Individuals with diverse expertise related to smoking cessation were empaneled to prioritize questions and outcomes important to clinicians. An evidence-synthesis team conducted systematic reviews, which informed recommendations to answer the questions. The GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach was used to rate the certainty in the estimated effects and the strength of recommendations.Results: The guideline panel formulated five strong recommendations and two conditional recommendations regarding pharmacotherapy choices. Strong recommendations include using varenicline rather than a nicotine patch, using varenicline rather than bupropion, using varenicline rather than a nicotine patch in adults with a comorbid psychiatric condition, initiating varenicline in adults even if they are unready to quit, and using controller therapy for an extended treatment duration greater than 12 weeks. Conditional recommendations include combining a nicotine patch with varenicline rather than using varenicline alone and using varenicline rather than electronic cigarettes.Conclusions: Seven recommendations are provided, which represent simple practice changes that are likely to increase the effectiveness of tobacco-dependence pharmacotherapy.

Transgenic expression of human CD47 reduces phagocytosis of porcine endothelial cells and podocytes by baboon and human macrophages.

BACKGROUND: Our initial studies utilizing a galactosyl-α1-3-galactosyltransferase gene knockout (GalTKO) pig-to-baboon renal transplant model demonstrated that the early development of nephrotic syndrome has been a significant obstacle to the long-term survival of baboon recipients. We have recently documented that sphingomyelin phosphodiesterase-3 (SMPDL3b) and CD80 expressed on podocytes in porcine kidney grafts contribute to this complication. We have hypothesized that one regulator of immune function is CD47 and that incompatibilities in CD47 between pig and baboon could potentially affect macrophage function, increasing the susceptibility of the kidney grafts to immunologically induced injury. METHODS: In order to address this hypothesis in vitro, we isolated and cultured porcine podocytes and ECs from GalTKO alone, human CD47 (hCD47)/hCD55 expressing transgenic (Tg) GalTKO swine, and GalTKO hCD46/hCD55 Tg swine along with baboon or human macrophages. RESULTS: We found that baboon macrophages phagocytosed porcine ECs in a similar manner to human macrophages, and this response was significantly reduced when porcine ECs and podocytes expressed hCD47/hCD55 but not hCD46/hCD55 without hCD47. Furthermore, masking hCD47 by anti-hCD47 antibody on hCD47/hCD55Tg ECs restored phagocytosis. These results are consistent with the hypothesis that CD47 incompatibility plays an important role in promoting macrophage phagocytosis of endogenous cells from the transplanted kidney. CONCLUSIONS: The similar levels of phagocytosis of porcine cells by baboon and human macrophages suggest that the expression of hCD47Tg on glomerular cells in donor porcine kidneys may prove to be a key strategy for preventing proteinuria following kidney xenotransplantation in a pig-to-human as well as a pig-to-baboon model.

Intra-bone bone marrow transplantation from hCD47 transgenic pigs to baboons prolongs chimerism to >60 days and promotes increased porcine lung transplant survival.

BACKGROUND: We have recently demonstrated that human-CD47 (hCD47) expressed on endothelial cells of porcine lung xenografts extended median graft survival from 3.5 days to 8.7 days in baboons. Intra-bone bone marrow transplantation (IBBMTx) in a pig-to-baboon model was previously shown to markedly prolong the duration of macrochimerism up to 21 days from 1 to 4 days by intravenous BMTx. We now examined whether the use of hCD47 transgenic (Tg) BM further prolonged the duration of chimerism following IBBMTx. We then tested if lung xenograft survival was prolonged following IBBMTx. METHODS: Baboons received GalTKO-hCD47/hCD55Tg (n = 5) or -hCD55Tg (n = 1) or -hCD46/HLA-E Tg (n = 1) pig IBBMTx. Macrochimerism, anti-pig T cells and antibody responses were assessed. Animals received lung xenografts from either hCD47+ or hCD47- porcine lungs 1-3 months later. RESULTS: All baboons that received hCD47Tg porcine IBBM maintained durable macrochimerism >30 days, and two maintained chimerism for >8 weeks. Notably, anti-pig antibody levels decreased over time and anti-pig cellular unresponsiveness developed following IBBMTx. Lungs from hCD47Tg IBBMTx matched pigs were transplanted at day 33 or day 49 after IBBMTx. These animals showed extended survival up to 13 and 14 days, while animals that received lungs from hCD47 negative pigs displayed no prolonged survival (1-4 days). CONCLUSION: This is the first report demonstrating durable macrochimerism beyond 8 weeks, as well as evidence for B cell tolerance in large animal xenotransplantation. Using hCD47Tg pigs as both IBBMTx and lung donors prolongs lung xenograft survival. However, additional strategies are required to control the acute loss of lung xenografts.

Pharmacokinetic and pharmacodynamic study of a clinically effective anti-CD2 monoclonal antibody.

The humanized IgG1κ monoclonal antibody siplizumab and its rat parent monoclonal IgG2b antibody BTI-322 are directed against the CD2 antigen. Siplizumab is species-specific, reacting with human and chimpanzee cells but not with cells from any other species, including other non-human primates. Because siplizumab treatment has recently shown great potential in clinical transplantation, we now present the results of our previous pharmacokinetic, pharmacodynamic and safety studies of both antibodies. Fourteen chimpanzees received 1-3 doses of 0.143 to 5.0 mg/kg iv The effects were followed with flow cytometry on peripheral lymphocytes and staining of lymph nodes. Side effects were recorded. Serum antibody concentrations were followed. Across the doses, a rapid, transient depletion of CD2, CD3, CD4 and CD8 lymphocytes and NK cells was observed for both antibodies. Immune reconstitution was more rapid for BTI-322 compared to siplizumab. Paracortical lymph node T cell depletion was moderate, estimated at 45% with doses of >0.6 mg/kg. Restoration of lymph node architecture was seen after two weeks to two months for all animals. All four subjects receiving BTI-322 experienced AEs on the first dosing day, while the eight subjects dosed with siplizumab experienced few mild, transient AEs. Infusion with siplizumab and BTI-322 resulted in rapid depletion of CD2+ cells in circulation and tissue. Siplizumab had a longer t1/2 and fewer AEs compared to BTI-322.

Development of transplantable B-cell lymphomas in the MHC-defined miniature swine model.

BACKGROUND: Establishment of transplantable tumors in clinically relevant large animals allows translational studies of novel cancer therapeutics. METHODS: Here we describe the establishment, characterization, and serial transplantation of a naturally occurring B-cell lymphoma derived from a unique, highly inbred sub-line of Massachusetts General Hospital (MGH) major histocompatibility complex (MHC)-defined miniature swine. RESULTS: The lymphoblastic cell line (LCL) originated from peripheral blood of a 2.5 year old female swine leukocyte antigen (SLA)dd-inbred miniature swine breeder demonstrating clinical signs of malignancy. Flow cytometric phenotypic analysis of subclones derived from the original cell line revealed surface markers commonly expressed in a B-cell lineage neoplasm. A subclone of the original LCL was transplanted into mildly-conditioned histocompatible miniature swine and immunocompromised NOD.Cg-Prkdc scid Il2rg tm1Wjl /SzJ (NSG) mice. Tissue and blood samples harvested 2 weeks following subcutaneous and intravenous injection in a highly inbred SLAdd pig were cultured for tumor growth and phenotypic analysis before serial transfer into NSG mice. Evidence of tumor growth in vivo was found in all tumor cell recipients. In vitro growth characteristics and surface phenotype were comparable between the original and serially transplanted tumor cell lines. CONCLUSIONS: These results indicate the feasibility of developing a large-animal transplantable tumor model using cells derived from spontaneously occurring hematologic malignancies within the highly inbred miniature swine herd.

Induction of human hemogenesis in adult fibroblasts by defined factors and hematopoietic coculture.

Transcription factor (TF)-based reprogramming of somatic tissues holds great promise for regenerative medicine. Previously, we demonstrated that the TFs GATA2, GFI1B, and FOS convert mouse and human fibroblasts to hemogenic endothelial-like precursors that generate hematopoietic stem progenitor (HSPC)-like cells over time. This conversion is lacking in robustness both in yield and biological function. Herein, we show that inclusion of GFI1 to the reprogramming cocktail significantly expands the HSPC-like population. AFT024 coculture imparts functional potential to these cells and allows quantification of stem cell frequency. Altogether, we demonstrate an improved human hemogenic induction protocol that could provide a valuable human in vitro model of hematopoiesis for disease modeling and a platform for cell-based therapeutics. DATABASE: Gene expression data are available in the Gene Expression Omnibus (GEO) database under the accession number GSE130361.

Haploidentical hematopoietic cell and kidney transplantation for hematological malignancies and end-stage renal failure.

At Massachusetts General Hospital, we pioneered simultaneous hematopoietic cell (HCT)/kidney transplantation from HLA-identical related donors for the treatment of hematological malignancies with end-stage renal failure. We have now extended this to HLA-haploidentical donors in a pilot trial. Six recipients, 5 of whom were conditioned with fludarabine, cyclophosphamide, and total-body irradiation, underwent combined HCT/kidney transplantation from haploidentical donors; graft-versus-host disease (GVHD) prophylaxis included post-HCT cyclophosphamide, tacrolimus, and mycophenolate mofetil. One patient died as a result of complications of fludarabine neurological toxicity. No neurological toxicity was observed in subsequent patients who received lower fludarabine doses and more intense postfludarabine dialysis. There were no cases of grade 2 to 4 acute GVHD and 1 case of moderate chronic GVHD by 12 months. One patient experienced relapse of multiple myeloma at 30 months after HCT and died 4 years posttransplantation. Overall, 4 of 6 patients remain alive, without disease relapse and with long-term renal rejection-free survival. This trial was registered at www.clinicaltrials.gov as #NCT01758042.

Twenty-year Follow-up of Histocompatibility Leukocyte Antigen-matched Kidney and Bone Marrow Cotransplantation for Multiple Myeloma With End-stage Renal Disease: Lessons Learned.

BACKGROUND: Specific immune tolerance of transplanted organs in association with either transient or sustained lymphohematopoietic chimerism has been demonstrated in several preclinical animal models and clinically in patients who are full donor chimeras after hematopoietic stem cell transplantation and subsequently received kidney transplants from the same donor. Most recently, tolerance induction has been extended to patients in whom chimerism was intentionally induced at the time of kidney transplantation. METHODS: Twenty years ago, we reported the first successful histocompatibility leukocyte antigen-matched sibling donor bone marrow and kidney transplant following nonmyeloablative conditioning in a patient with multiple myeloma and end-stage renal disease (ESRD). After 2 decades, she has normal renal function in the absence of ongoing systemic immunosuppressive therapy. Nine patients have subsequently undergone similar treatment for multiple myeloma with ESRD. RESULTS: In the initial patient, hematopoietic chimerism was detectable for only 105 days after the transplant. In subsequent patients, chimerism detection ranged from 49 days to >14 years. Nevertheless, a long remission of the myeloma and long-term immunosuppression-free survival of the kidney allograft were achieved in 7 of the 10 patients, 5 of whom currently survive. CONCLUSIONS: This initial patient demonstrated the feasibility of performing combined histocompatibility leukocyte antigen-matched, sibling donor bone marrow and kidney transplantation for ESRD due to multiple myeloma. This experience paved the way for extending the initial trial to 9 additional patients with multiple myeloma and ESRD and, more recently, to tolerance induction strategies involving combined bone marrow and kidney transplantation for patients with and without an underlying malignancy.

Recommendations for the Appropriate Structure, Communication, and Investigation of Tobacco Harm Reduction Claims. An Official American Thoracic Society Policy Statement.

RATIONALE: The tobacco harm reduction literature is replete with vague language, far-reaching claims, and unwarranted certainty. The American Thoracic Society has increasingly recognized the need for a framework for reliably making such claims. Evidence-based standards improving the scientific value and transparency of harm reduction claims are expected to improve their trustworthiness, clarity, and consistency. METHODS: Experts from relevant American Thoracic Society committees identified key topic areas for discussion. Literature search strategy included English language articles across Medline, Google Scholar, and the Cochrane Collaborative databases, with expanded search terms including tobacco, addiction, smoking, cigarettes, nicotine, and harm reduction. Workgroup members synthesized their evidentiary summaries into a list of candidate topics suitable for inclusion in the final report. Breakout groups developed detailed content maps of each topic area, including points to be considered for suggested recommendations. Successive draft recommendations were modified using an iterative consensus process until unanimous approval was achieved. Patient representatives ensured the document's relevance to the lay public. RESULTS: Fifteen recommendations were identified, organized into four framework elements dealing with: estimating harm reduction among individuals, making claims on the basis of population impact, appropriately careful use of language, and ethical considerations in harm reduction. DISCUSSION: This statement clarifies important principles guiding valid direct and inferential harm reduction claims. Ideals for effective communication with the lay public and attention to unique ethical concerns are also delineated. The authors call for formal systems of grading harm reduction evidence and regulatory assurances of longitudinal surveillance systems to document the impact of harm reduction policies.

Transplantation tolerance through mixed chimerism: From allo to xeno.

To date, the only successful means of achieving allogeneic transplantation tolerance in the clinic has involved induction of mixed lymphohematopoietic chimerism. Such chimerism was first achieved in mice and subsequently in large animals, including miniature swine, monkeys and most recently humans. The mechanism of tolerance has differed between models, involving both deletional and regulatory mechanisms, in varying proportions, depending on the model. Considerable progress has also been made toward induction of tolerance across the xenogeneic pig-to-primate barrier, although complete success has not yet been achieved. The two approaches toward xenograft tolerance currently being investigated both involve establishment of a mixture of host and donor cells in the thymus, in one case through administration of donor bone marrow to the recipient and in the other through vascularized donor thymus transplantation to a thymectomized recipient. Hopefully, a combination of these approaches may provide an effective means for achieving full tolerance and thereby bringing xenograft organ transplantation to the clinic.

Dosing optimization of CCR4 immunotoxin for improved depletion of CCR4+ Treg in nonhuman primates.

Recently, we have developed a diphtheria toxin-based recombinant anti-human CCR4 immunotoxin for targeting CCR4+ tumors and Tregs. In this study, we further optimized the dosing schedule for improved CCR4+ Treg depletion. We have demonstrated that up to a 90% depletion was achieved and the depletion extended to approximately 2 weeks in the peripheral blood and more than 48 days in the lymph node at 25 µg·kg-1 , BID for 8 consecutive days in cynomolgus monkeys. Expansion was observed including monocytes and NK cells. Antibody against the CCR4 immunotoxin was detected after approximately 2 weeks, affecting further depletion efficacy for multiple course treatment.

Upregulation of CD80 on glomerular podocytes plays an important role in development of proteinuria following pig-to-baboon xeno-renal transplantation - an experimental study.

We have previously reported that co-transplantation of the kidney with vascularized donor thymus from α-1,3-galactosyltransferase gene knockout pigs with an anti-CD154 with rituximab-based regimen led to improved xenograft survival in baboons with donor-specific unresponsiveness. However, nephrotic syndrome emerged as a complication in which the glomeruli showed mild mesangial expansion with similarities to minimal change disease (MCD) in humans. Since MCD is associated with CD80 expression in glomeruli and elevated urinary excretion, we evaluated a potential role for CD80 in xenograft nephropathy. Study 1 confirmed high urinary CD80 excretion in nephrotic animals with renal xenografts showing CD80 expression in glomeruli. In Study 2, baboons receiving xenografts received CTLA4-Ig once a week from the second postoperative week or no CTLA4-Ig. The non-CTLA4-Ig group developed severe proteinuria with modest mesangial expansion with high urinary excretion of CD80 and documented CD80 expression in glomerular podocytes. All of the recipients in non-CTLA4-Ig groups had to be euthanized before POD 60. In contrast, CTLA4-Ig group showed a marked reduction in proteinuria and survived significantly longer, up to 193 days. These results demonstrate that anti-CD80 targeted therapy represents a promising strategy for reduction of proteinuria following renal xeno-transplantation with improved survival.

Absence of interaction between porcine endogenous retrovirus and porcine cytomegalovirus in pig-to-baboon renal xenotransplantation in vivo.

BACKGROUND: Studies of xenotransplantation from swine have identified porcine viruses as potential barriers to clinical trials. The biology of these viruses has not been extensively investigated in the in vivo xeno-environment. Enhancement of viral gene expression by viral and cellular factors acting in trans has been demonstrated for certain viruses, including bidirectional interactions between human herpesviruses and endogenous (HERV) and exogenous (HIV) retroviruses. Both porcine cytomegalovirus (PCMV) and porcine endogenous retrovirus (PERV) infections have been identified in xenografts from swine. PERV receptors exist on human cells with productive infection in vitro in permissive human target cell lines. PCMV is largely species-specific with infection restricted to the xenograft in pig-to-baboon transplants. It is unknown whether coinfection by PCMV affects the replication of PERV within xenograft tissues which might have implications for the risk of retroviral infection in the human host. METHODS: A series of 11 functioning, life-supporting pig-to-baboon kidney xenografts from PERV-positive miniature swine were studied with and without PCMV co-infection. Frozen biopsy samples were analyzed using quantitative, real-time PCR with internal controls. RESULTS: PERV replication was not altered in the presence of PCMV coinfection (P = .70). The absence of variation with coinfection was confirmed when PERV quantitation was expressed relative to simultaneous cellular GAPDH levels with or without PCMV coinfection (P = .59). CONCLUSIONS: PCMV coinfection does not alter the replication of PERV in life-supporting renal xenotransplantation in vivo in baboons.

The effects of galectin-3 depletion apheresis on induced skin inflammation in a porcine model.

Galectin-3 (Gal-3), a ß-galactoside-binding lectin that is expressed in mammalian cells, is known to modulate several biological functions such as cell-cell adhesion, macrophage activation, angiogenesis, metastasis, and fibrosis. The goal of this study was to evaluate the ability of Gal-3 depletion apheresis using an adsorption column with immobilized anti-Gal-3-antibody to reduce inflammation induced by Complete Freund's Adjuvant injection in a skin inflammation porcine model. Here, we report that plasma perfusion by apheresis through a Gal-3 binding immuno-affinity column reduces plasma Gal-3 levels to below limits of quantitative detection, and results in significant decrease in skin inflammation, including degree and duration of inflammatory lesions. Human plasma was tested ex vivo and found to be efficiently depleted using the anti-Gal-3 affinity column. This study demonstrates the potential of Gal-3 depletion apheresis as a therapeutic method for inflammation-mediated disease, supporting continued research in this area for clinical application.