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1.
Nature ; 626(8000): 827-835, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38355791

RESUMO

Individuals differ widely in their immune responses, with age, sex and genetic factors having major roles in this inherent variability1-6. However, the variables that drive such differences in cytokine secretion-a crucial component of the host response to immune challenges-remain poorly defined. Here we investigated 136 variables and identified smoking, cytomegalovirus latent infection and body mass index as major contributors to variability in cytokine response, with effects of comparable magnitudes with age, sex and genetics. We find that smoking influences both innate and adaptive immune responses. Notably, its effect on innate responses is quickly lost after smoking cessation and is specifically associated with plasma levels of CEACAM6, whereas its effect on adaptive responses persists long after individuals quit smoking and is associated with epigenetic memory. This is supported by the association of the past smoking effect on cytokine responses with DNA methylation at specific signal trans-activators and regulators of metabolism. Our findings identify three novel variables associated with cytokine secretion variability and reveal roles for smoking in the short- and long-term regulation of immune responses. These results have potential clinical implications for the risk of developing infections, cancers or autoimmune diseases.


Assuntos
Imunidade Adaptativa , Fumar , Feminino , Humanos , Masculino , Imunidade Adaptativa/efeitos dos fármacos , Imunidade Adaptativa/genética , Doenças Autoimunes/etiologia , Doenças Autoimunes/imunologia , Índice de Massa Corporal , Citocinas/sangue , Citocinas/imunologia , Citomegalovirus/imunologia , Citomegalovirus/patogenicidade , Citomegalovirus/fisiologia , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/genética , Infecções/etiologia , Infecções/imunologia , Neoplasias/etiologia , Neoplasias/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Fumar/efeitos adversos , Fumar/sangue , Fumar/genética , Fumar/imunologia
2.
Surg Endosc ; 37(12): 9483-9508, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37700015

RESUMO

BACKGROUND: Transanal TME (taTME) combines abdominal and transanal dissection to facilitate sphincter preservation in patients with low rectal tumors. Few phase II/III trials report long-term oncologic and functional results. We report early results from a North American prospective multicenter phase II trial of taTME (NCT03144765). METHODS: 100 patients with stage I-III rectal adenocarcinoma located ≤ 10 cm from the anal verge (AV) were enrolled across 11 centers. Primary and secondary endpoints were TME quality, pathologic outcomes, 30-day and 90-day outcomes, and stoma closure rate. Univariable regression analysis was performed to assess risk factors for incomplete TME and anastomotic complications. RESULTS: Between September 2017 and April 2022, 70 males and 30 females with median age of 58 (IQR 49-62) years and BMI 27.8 (IQR 23.9-31.8) kg/m2 underwent 2-team taTME for tumors located a median 5.8 (IQR 4.5-7.0) cm from the AV. Neoadjuvant radiotherapy was completed in 69%. Intersphincteric resection was performed in 36% and all patients were diverted. Intraoperative complications occurred in 8% including 3 organ injuries, 2 abdominal and 1 transanal conversion. The 30-day and 90-day morbidity rates were 49% (Clavien-Dindo (CD) ≥ 3 in 28.6%) and 56% (CD ≥ 3 in 30.4% including 1 mortality), respectively. Anastomotic complications were reported in 18% including 10% diagnosed within 30 days. Higher anastomotic risk was noted among males (p = 0.05). At a median follow-up of 5 (IQR 3.1-7.4) months, 98% of stomas were closed. TME grade was complete or near complete in 90%, with positive margins in 2 cases (3%). Risk factors for incomplete TME were ASA ≥ 3 (p = 0.01), increased time between NRT and surgery (p = 0.03), and higher operative blood loss (p = 0.003). CONCLUSION: When performed at expert centers, 2-team taTME in patients with low rectal tumors is safe with low conversion rates and high stoma closure rate. Mid-term results will further evaluate oncologic and functional outcomes.


Assuntos
Laparoscopia , Protectomia , Neoplasias Retais , Cirurgia Endoscópica Transanal , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Reto/cirurgia , Reto/patologia , Estudos Prospectivos , Cirurgia Endoscópica Transanal/métodos , Neoplasias Retais/patologia , Protectomia/métodos , Laparoscopia/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/patologia , Resultado do Tratamento
3.
Ann Surg ; 278(3): 452-463, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37450694

RESUMO

OBJECTIVES: To report the results of a rigorous quality control (QC) process in the grading of total mesorectal excision (TME) specimens during a multicenter prospective phase 2 trial of transanal TME. BACKGROUND: Grading of TME specimens is based on the macroscopic assessment of the mesorectum and standardized through synoptic pathology reporting. TME grade is a strong predictor of outcomes with incomplete (IC) TME associated with increased rates of local recurrence relative to complete or near complete (NC) TME. Although TME grade serves as an endpoint in most rectal cancer trials, in protocols incorporating centralized review of TME specimens for quality assurance, discordance in grading and the management thereof has not been previously described. METHODS: A phase 2 prospective transanal TME trial was conducted from 2017 to 2022 across 11 North American centers with TME quality as the primary study endpoint. QC measures included (1) training of site pathologists in TME protocols, (2) blinded grading of de-identified TME specimen photographs by central pathologists, and (3) reconciliation of major discordance before trial reporting. Cohen Kappa statistic was used to assess agreement in grading. RESULTS: Overall agreement in grading of 100 TME specimens between site and central reviewer was rated as fair, (κ = 0.35; 95% CI: 0.10-0.61; P < 0.0001). Concordance was noted in 54%, with minor and major discordance in 32% and 14% of cases, respectively. Upon reconciliation, 13/14 (93%) major discordances were resolved. Pre versus postreconciliation rates of complete or NC and IC TME are 77%/16% and 7% versus 69%/21% and 10%. Reconciliation resulted in a major upgrade (IC-NC; N = 1) or major downgrade (NC/C-IC, N = 4) in 5 cases overall (5%). CONCLUSIONS: A 14% rate of major discordance was observed in TME grading between the site and central reviewers. The resolution resulted in a major change in final TME grade in 5% of cases, which suggests that reported rates or TME completeness are likely overestimated in trials. QC through a central review of TME photographs and reconciliation of major discordances is strongly recommended.


Assuntos
Laparoscopia , Mesocolo , Protectomia , Neoplasias Retais , Humanos , Reto/cirurgia , Estudos Prospectivos , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia , Protectomia/métodos , Mesocolo/cirurgia , Resultado do Tratamento , Laparoscopia/métodos
4.
Surg Endosc ; 37(9): 7336-7347, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37474823

RESUMO

BACKGROUND: Intraoperative ureteral injury, a serious complication of abdominopelvic surgeries, can be avoided through ureter visualization. Near-infrared fluorescence imaging offers real-time anatomical visualization of ureters during surgery. Pudexacianinium (ASP5354) chloride is an indocyanine green derivative under investigation for intraoperative ureter visualization during colorectal or gynecologic surgery in adult and pediatric patients. METHODS: In this phase 2 study (NCT04238481), adults undergoing laparoscopic colorectal surgery were randomized to receive one intravenous dose of pudexacianinium 0.3 mg, 1.0 mg, or 3.0 mg. The primary endpoint was successful intraoperative ureter visualization, defined as observation of ureter fluorescence 30 min after pudexacianinium administration and at end of surgery. Safety and pharmacokinetics were also assessed. RESULTS: Participants received pudexacianinium 0.3 mg (n = 3), 1.0 mg (n = 6), or 3.0 mg (n = 3). Most participants were female (n = 10; 83.3%); median age was 54 years (range 24-69) and median BMI was 29.3 kg/m2 (range 18.7-38.1). Successful intraoperative ureter visualization occurred in 2/3, 5/6, and 3/3 participants who received pudexacianinium 0.3 mg, 1.0 mg, or 3.0 mg, respectively. Median intensity values per surgeon assessment were 1 (mild) with the 0.3-mg dose, 2 (moderate) with the 1.0-mg dose, and 3 (strong) with the 3.0-mg dose. A correlation was observed between qualitative (surgeon's recognition/identification of the ureter during surgery) and quantitative (video recordings of the surgeries after study completion) assessment of fluorescence intensity. Two participants experienced serious adverse events, none of which were drug-related toxicities. One adverse event (grade 1 proteinuria) was related to pudexacianinium. Plasma pudexacianinium concentrations were dose-dependent and the mean (± SD) percent excreted into urine during surgery was 22.3% ± 8.0% (0.3-mg dose), 15.6% ± 10.0% (1.0-mg dose), and 39.5% ± 12.4% (3.0-mg dose). CONCLUSIONS: In this study, 1.0 and 3.0 mg pudexacianinium provided ureteral visualization for the duration of minimally invasive, laparoscopic colorectal procedures and was safe and well tolerated.


Assuntos
Neoplasias Colorretais , Cirurgia Colorretal , Laparoscopia , Ureter , Adulto , Humanos , Feminino , Criança , Adulto Jovem , Pessoa de Meia-Idade , Idoso , Masculino , Ureter/diagnóstico por imagem , Ureter/cirurgia , Ureter/lesões , Cloretos , Cirurgia Colorretal/efeitos adversos , Corantes Fluorescentes , Laparoscopia/métodos , Verde de Indocianina , Neoplasias Colorretais/cirurgia
5.
Transl Cancer Res ; 12(4): 1049-1053, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37180674

RESUMO

Background: Rectal diverticula are a very rare occurrence compared to diverticula of the colon. They are reported to account for only 0.08% of all diverticulosis. Diverticula of the rectum can be caused by congenital or acquired factors. The majority are asymptomatic, diagnosed incidentally, and require no treatment. The low incidence of rectal diverticulosis may be attributed to the unique anatomical structure and physiological environment of the rectum. However, complications can arise and may necessitate surgical or endoscopic treatment. Case Description: We report the case of a 72-year-old female with a history of diabetes mellitus, hyperlipidemia, and hypothyroidism who presented to the colorectal surgery clinic with symptoms of constipation of nearly a 50-year duration. The patient underwent an anorectal exam under anesthesia which revealed a 3 cm defect in the left levator muscles with herniated rectal wall. A large left lateral rectal diverticulum was diagnosed during the work-up for pelvic organ prolapse on defecography. She underwent robotic assisted ventral mesh rectopexy and recovered uneventfully. After 1 year of follow-up, the patient is asymptomatic, and the control colonoscopy shows no signs of the rectal diverticulum. Conclusions: Rectal diverticula can present in the setting of pelvic organ prolapse and can be safely managed with ventral mesh rectopexy.

6.
Opt Express ; 31(1): 564-571, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36606992

RESUMO

A design method for the creation of photons with fractional orbital angular momentum (FOAM) is reported through the use of a metal-wedge optical fiber. The main focus was on a limiting zero-degree metal wedge, the case of light beams carrying ±â„2 OAM per photon. We compared this ideal case with a one-degree metal wedge in hopes of encouraging experimentalists to fabricate this type of waveguide. Various intensity and the Poynting vector plots for different modes and varying wedge angles were obtained and analyzed. We found that the Poynting vectors in the transverse direction for the zero and one degree metal wedges were essentially identical. In addition, as the metal wedge angle was increased, the real propagation constant decreased. Furthermore, the metal wedge enables a new method to obtain a local field enhancement in the center of the core of this waveguide, thus providing a wide range of applications in other fields. Finally, we found discrete complex propagation constants leading to discrete leaky modes with potentially an infinite number of these modes.

7.
Cell Rep Med ; 4(2): 100920, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36706753

RESUMO

While the association between colorectal cancer (CRC) features and Fusobacterium has been extensively studied, less is known of other intratumoral bacteria. Here, we leverage whole transcriptomes from 807 CRC samples to dually characterize tumor gene expression and 74 intratumoral bacteria. Seventeen of these species, including 4 Fusobacterium spp., are classified as orally derived and are enriched among right-sided, microsatellite instability-high (MSI-H), and BRAF-mutant tumors. Across consensus molecular subtypes (CMSs), integration of Fusobacterium animalis (Fa) presence and tumor expression reveals that Fa has the most significant associations in mesenchymal CMS4 tumors despite a lower prevalence than in immune CMS1. Within CMS4, the prevalence of Fa is uniquely associated with collagen- and immune-related pathways. Additional Fa pangenome analysis reveals that stress response genes and the adhesion FadA are commonly expressed intratumorally. Overall, this study identifies oral-derived bacteria as enriched in inflamed tumors, and the associations of bacteria and tumor expression are context and species specific.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/genética , Fusobacterium/genética , Instabilidade de Microssatélites , Transcriptoma
9.
Am Surg ; 89(11): 4908-4909, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34455863

RESUMO

Rhodococcus hoagii (formerly Rhodococcus equi), originally isolated from equine species, is primarily transmitted through inhalation of contaminated aerosols such as dust and even breath of infected livestock. Pasteurella multocida is a common cause of cellulitis secondary to canine and feline bites. These are 2 zoonotic microbes that can present with potentially life-threatening, systematic illness in immunocompromised patients.In this brief report, we delineate the clinical course of a 42-year-old post-operative patient (status post-elective exploratory laparotomy, extensive adhesiolysis, and excision of enterocutaneous fistula with creation of an end ileostomy) who developed multiple infections involving these two zoonotic microbes. The patient is an enthusiast of exotic animals with an extensive occupational history as a zookeeper. She was determined to be HIV negative but has a significant history of Crohn's disease managed with systemic immunosuppressive therapy. This case highlights her unusual constellation of post-operative infections and her subsequent medical management.


Assuntos
Doenças do Gato , Doenças do Cão , Infecções por Pasteurella , Pasteurella multocida , Humanos , Feminino , Animais , Gatos , Cães , Cavalos , Adulto , Infecções por Pasteurella/tratamento farmacológico , Infecção da Ferida Cirúrgica/diagnóstico , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/terapia
10.
Nat Commun ; 13(1): 5895, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36202838

RESUMO

Epigenetic changes are required for normal development, yet the nature and respective contribution of factors that drive epigenetic variation in humans remain to be fully characterized. Here, we assessed how the blood DNA methylome of 884 adults is affected by DNA sequence variation, age, sex and 139 factors relating to life habits and immunity. Furthermore, we investigated whether these effects are mediated or not by changes in cellular composition, measured by deep immunophenotyping. We show that DNA methylation differs substantially between naïve and memory T cells, supporting the need for adjustment on these cell-types. By doing so, we find that latent cytomegalovirus infection drives DNA methylation variation and provide further support that the increased dispersion of DNA methylation with aging is due to epigenetic drift. Finally, our results indicate that cellular composition and DNA sequence variation are the strongest predictors of DNA methylation, highlighting critical factors for medical epigenomics studies.


Assuntos
Metilação de DNA , Epigenômica , Adulto , Envelhecimento/genética , Epigênese Genética , Epigenômica/métodos , Humanos , Fatores Imunológicos
11.
Cell Rep ; 39(13): 110989, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35767946

RESUMO

The interleukin-12 (IL-12) family comprises the only heterodimeric cytokines mediating diverse functional effects. We previously reported a striking bimodal IL-12p70 response to lipopolysaccharide (LPS) stimulation in healthy donors. Herein, we demonstrate that interferon ß (IFNß) is a major upstream determinant of IL-12p70 production, which is also associated with numbers and activation of circulating monocytes. Integrative modeling of proteomic, genetic, epigenomic, and cellular data confirms IFNß as key for LPS-induced IL-12p70 and allowed us to compare the relative effects of each of these parameters on variable cytokine responses. Clinical relevance of our findings is supported by reduced IFNß-IL-12p70 responses in patients hospitalized with acute severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or chronically infected with hepatitis C (HCV). Importantly, these responses are resolved after viral clearance. Our systems immunology approach defines a better understanding of IL-12p70 and IFNß in healthy and infected persons, providing insights into how common genetic and epigenetic variation may impact immune responses to bacterial infection.


Assuntos
Interferon beta , Interleucina-12 , Receptor 4 Toll-Like , COVID-19/imunologia , COVID-19/metabolismo , COVID-19/virologia , Citocinas/imunologia , Citocinas/metabolismo , Humanos , Interferon beta/imunologia , Interferon beta/metabolismo , Interleucina-12/imunologia , Interleucina-12/metabolismo , Lipopolissacarídeos/farmacologia , Proteômica , SARS-CoV-2/imunologia
13.
Nat Immunol ; 23(4): 568-580, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35314846

RESUMO

Tumor-associated macrophages are composed of distinct populations arising from monocytes or tissue macrophages, with a poorly understood link to disease pathogenesis. Here, we demonstrate that mouse monocyte migration was supported by glutaminyl-peptide cyclotransferase-like (QPCTL), an intracellular enzyme that mediates N-terminal modification of several substrates, including the monocyte chemoattractants CCL2 and CCL7, protecting them from proteolytic inactivation. Knockout of Qpctl disrupted monocyte homeostasis, attenuated tumor growth and reshaped myeloid cell infiltration, with loss of monocyte-derived populations with immunosuppressive and pro-angiogenic profiles. Antibody targeting of the receptor CSF1R, which more broadly eliminates tumor-associated macrophages, reversed tumor growth inhibition in Qpctl-/- mice and prevented lymphocyte infiltration. Modulation of QPCTL synergized with anti-PD-L1 to expand CD8+ T cells and limit tumor growth. QPCTL inhibition constitutes an effective approach for myeloid cell-targeted cancer immunotherapy.


Assuntos
Aminoaciltransferases , Linfócitos T CD8-Positivos , Quimiocinas , Neoplasias , Aminoaciltransferases/genética , Aminoaciltransferases/metabolismo , Animais , Linfócitos T CD8-Positivos/patologia , Quimiocinas/metabolismo , Imunoterapia , Infiltração Leucêmica , Camundongos , Camundongos Knockout , Monócitos , Neoplasias/imunologia
14.
Genome Med ; 14(1): 28, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35264221

RESUMO

BACKGROUND: Blood plasma proteins play an important role in immune defense against pathogens, including cytokine signaling, the complement system, and the acute-phase response. Recent large-scale studies have reported genetic (i.e., protein quantitative trait loci, pQTLs) and non-genetic factors, such as age and sex, as major determinants to inter-individual variability in immune response variation. However, the contribution of blood-cell composition to plasma protein heterogeneity has not been fully characterized and may act as a mediating factor in association studies. METHODS: Here, we evaluated plasma protein levels from 400 unrelated healthy individuals of western European ancestry, who were stratified by sex and two decades of life (20-29 and 60-69 years), from the Milieu Intérieur cohort. We quantified 229 proteins by Luminex in a clinically certified laboratory and their levels of variation were analyzed together with 5.2 million single-nucleotide polymorphisms. With respect to non-genetic variables, we included 254 lifestyle and biochemical factors, as well as counts of seven circulating immune cell populations measured by hemogram and standardized flow cytometry. RESULTS: Collectively, we found 152 significant associations involving 49 proteins and 20 non-genetic variables. Consistent with previous studies, age and sex showed a global, pervasive impact on plasma protein heterogeneity, while body mass index and other health status variables were among the non-genetic factors with the highest number of associations. After controlling for these covariates, we identified 100 and 12 pQTLs acting in cis and trans, respectively, collectively associated with 87 plasma proteins and including 19 novel genetic associations. Genetic factors explained the largest fraction of the variability of plasma protein levels, as compared to non-genetic factors. In addition, blood-cell fractions, including leukocytes, lymphocytes, monocytes, neutrophils, eosinophils, basophils, and platelets, had a larger contribution to inter-individual variability than age and sex and appeared as confounders of specific genetic associations. Finally, we identified new genetic associations with plasma protein levels of five monogenic Mendelian disease genes including two primary immunodeficiency genes (Ficolin-3 and FAS). CONCLUSIONS: Our study identified novel genetic and non-genetic factors associated to plasma protein levels which may inform health status and disease management.


Assuntos
Proteínas Sanguíneas , Doenças da Imunodeficiência Primária , Proteínas Sanguíneas/genética , Estudo de Associação Genômica Ampla , Nível de Saúde , Humanos , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
15.
Clin Colon Rectal Surg ; 35(2): 93-98, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35237103

RESUMO

Transanal endoscopic surgery encompasses the minimally invasive surgical techniques used to operate in the rectum under magnification while maintaining pneumorectum via a resectoscope or port. The view, magnification, and surgical precision afforded by these advanced transanal techniques have resulted in excellent specimen quality and low recurrence rates, especially compared with traditional transanal surgery. For rigid platforms, the surgeon operates through a rigid 4-cm diameter steel proctoscope of varying lengths that is clamped to the operating table with an articulating arm. Transanal minimally invasive surgery (TAMIS) is a newer flexible platform using a disposable port which "hooks" into the anorectal ring to remain in place. The cost-effectiveness and versatility of the TAMIS platform have resulted in its popularity and use in more advanced applications such as transanal total mesorectal excision. Ultimately, the choice of operating platform should be based on surgeon preference, patient characteristics, availability, and cost. The pros and cons of each platform will be discussed in this article.

17.
Front Immunol ; 13: 897193, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36591308

RESUMO

Tuberculosis (TB) remains a major public health problem and we lack a comprehensive understanding of how Mycobacterium tuberculosis (M. tb) infection impacts host immune responses. We compared the induced immune response to TB antigen, BCG and IL-1ß stimulation between latently M. tb infected individuals (LTBI) and active TB patients. This revealed distinct responses between TB/LTBI at transcriptomic, proteomic and metabolomic levels. At baseline, we identified a novel immune-metabolic association between pregnane steroids, the PPARγ pathway and elevated plasma IL-1ra in TB. We observed dysregulated IL-1 responses after BCG stimulation in TB patients, with elevated IL-1ra responses being explained by upstream TNF differences. Additionally, distinct secretion of IL-1α/IL-1ß in LTBI/TB after BCG stimulation was associated with downstream differences in granzyme mediated cleavage. Finally, IL-1ß driven signalling was dramatically perturbed in TB disease but was completely restored after successful treatment. This study improves our knowledge of how immune responses are altered during TB disease, and may support the design of improved preventive and therapeutic tools, including host-directed strategies.


Assuntos
Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-1 , Tuberculose , Humanos , Vacina BCG , Proteína Antagonista do Receptor de Interleucina 1/genética , Proteína Antagonista do Receptor de Interleucina 1/imunologia , Interleucina-1/genética , Interleucina-1/imunologia , Redes e Vias Metabólicas , Proteômica , Tuberculose/tratamento farmacológico , Tuberculose/genética , Tuberculose/imunologia
18.
Bioorg Chem ; 116: 105376, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34560560

RESUMO

Antitumor immune responses depend on the infiltration of solid tumors by effector T cells, a process guided by chemokines. In particular, the chemokine CXCL10 has been shown to play a critical role in mediating recruitment of CXCR3 + cytolytic T and NK cells in tumors, though its use as a therapeutic agent has not been widely explored. One of the limitations is due to the rapid inactivation of CXCL10 by dipeptidyl peptidase 4 (DPP4), a broadly expressed enzyme that is active in plasma and other bodily fluids. In the present study, we describe a novel method to produce synthetic CXCL10 that is resistant to DPP4 N-terminal truncation. Using a Fmoc solid-phase peptide synthesis approach, synthetic murine WT CXCL10 was produced, showing similar biochemical and biological properties to the recombinant protein. This synthesis method supported production of natural (amino acid substitution, insertion or deletion) and non-natural (chemical modifications) variants of CXCL10. In association with a functional screening cascade that assessed DPP4-mediated cleavage, CXCR3 signaling potency and chemotactic activity, we successfully generated 20 murine CXCL10 variants. Among those, two non-natural variants with N-methylated Leu3 (MeLeu3) and a reduced amide bond between Pro2 and Leu3 (rLeu3), respectively, showed resistance to DPP4 truncation but decreased CXCR3 signaling and chemotactic activity. Interestingly, MeLeu3 and rLeu3 CXCL10 behaved as DPP4 inhibitors, preventing the truncation of WT CXCL10. This study highlights the potential of using Fmoc solid-phase chemistry in association with biochemical and biological characterization to rapidly identify CXCL10 variants with desired properties. These novel methods unlock the opportunity to develop DPP4 resistant CXCL10 variants, as well as other chemokine substrates, while maintaining chemotactic properties.


Assuntos
Quimiocina CXCL10/farmacologia , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/farmacologia , Quimiocina CXCL10/síntese química , Quimiocina CXCL10/química , Inibidores da Dipeptidil Peptidase IV/síntese química , Inibidores da Dipeptidil Peptidase IV/química , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
19.
Surg Technol Int ; 39: 137-145, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34380172

RESUMO

Colorectal cancer remains the 3rd most common cancer diagnosed among men and women in the United States. With improved screening, premalignant rectal lesions and rectal cancers are being detected at earlier stages. In addition, the use of neoadjuvant chemo- and radiotherapy has led to downstaging of larger lesions. There is growing interest among colorectal surgeons in local excision with organ preservation for patients with rectal cancer. There are multiple platforms for local excision of rectal cancers, including transanal excision (TAE), transanal endoscopic microsurgery (TEM) and transanal minimally invasive surgery (TAMIS). TAMIS was developed as an affordable platform that uses conventional laparoscopic equipment familiar to many colorectal surgeons. TAMIS allows for full-thickness benign or malignant lesion excision in any quadrant without the need for patient repositioning. The literature has shown that, for appropriately selected patients, TAMIS provides superior excision quality compared to TAE. Furthermore, TAMIS has oncologic outcomes equivalent to TEM at a fraction of the cost. Recently, robotic TAMIS has been introduced, which takes advantage of the articulating instruments of the robotic platform without the need for a skilled assistant. This article will cover multiple technical aspects for TAMIS including patient selection and preparation, technical tips for successful excision and defect closure, and recent advances, including robotic TAMIS.


Assuntos
Laparoscopia , Neoplasias Retais , Robótica , Cirurgia Endoscópica Transanal , Feminino , Humanos , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos , Neoplasias Retais/cirurgia , Reto
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