Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 73
Filtrar
1.
iScience ; 27(3): 109191, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38433928

RESUMEN

The paucity of preclinical models that recapitulate COVID-19 pathology without requiring SARS-COV-2 adaptation and humanized/transgenic mice limits research into new therapeutics against the frequently emerging variants-of-concern. We developed virus-free models by C57BL/6 mice receiving oropharyngeal instillations of a SARS-COV-2 ribo-oligonucleotide common in all variants or specific to Delta/Omicron variants, concurrently with low-dose bleomycin. Mice developed COVID-19-like lung pathologies including ground-glass opacities, interstitial fibrosis, congested alveoli, and became moribund. Lung tissues from these mice and bronchoalveolar lavage and lung tissues from patients with COVID-19 showed elevated levels of hyaluronic acid (HA), HA-family members, an inflammatory signature, and immune cell infiltration. 4-methylumbelliferone (4-MU), an oral drug for biliary-spasm treatment, inhibits HA-synthesis. At the human equivalent dose, 4-MU prevented/inhibited COVID-19-like pathologies and long-term morbidity; 4-MU and metabolites accumulated in mice lungs. Therefore, these versatile SARS-COV-2 ribo-oligonucleotide oropharyngeal models recapitulate COVID-19 pathology, with HA as its critical mediator and 4-MU as a potential therapeutic for COVID-19.

2.
J Appl Lab Med ; 9(2): 350-356, 2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38180079

RESUMEN

BACKGROUND: Examination of urine by immunofixation electrophoresis (UIFE) is one of the tests recommended for screening and monitoring of monoclonal gammopathies, especially multiple myeloma. Unlike the serum free light chain measurement, a positive result on urine immunofixation is diagnostic for monoclonal immunoglobulin light chains. Urine is usually concentrated, generally by membrane filtration, prior to electrophoresis. METHODS: Alternative methods to membrane filtration for urine concentration were examined. Residual urine specimens submitted for urine protein electrophoresis were concentrated by precipitation of the proteins by ammonium sulfate salt precipitation, precipitation with ethanol and acetonitrile, and by desiccation. The concentrated specimens were subjected to immunofixation electrophoresis using antisera to free light chains (FLC). The results were compared with those from conventional immunofixation electrophoresis using specimens concentrated by membrane filtration. RESULTS: Ammonium sulfate, ethanol, and acetonitrile precipitation results were less than satisfactory. Concentration by desiccation provided results comparable, if not better than, those by membrane filtration and conventional UIFE. The cost of desiccation is minimal compared to more than $5.00/specimen cost of concentration by membrane filtration. The differences in the results with conventional UIFE and the method described here are likely due to (a) variability in the reactivity of different antisera to free monoclonal light chains, and (b) obscuration of monoclonal free light chains by co-migration with intact immunoglobulin monoclonal proteins. CONCLUSIONS: Concentrating urine by desiccation for immunofixation electrophoresis is technically simple, inexpensive, and provides results comparable to concentrating by membrane filtration. Using FLC provides a more sensitive assay than using conventional antisera.


Asunto(s)
Gammopatía Monoclonal de Relevancia Indeterminada , Humanos , Sulfato de Amonio , Cadenas Ligeras de Inmunoglobulina , Acetonitrilos , Etanol , Sueros Inmunes
3.
J Appl Lab Med ; 8(6): 1101-1114, 2023 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-37725944

RESUMEN

BACKGROUND: The serum-free immunoglobulin light chain assay has been recommended as a screening test for monoclonal gammopathy. We evaluated the usefulness of urine free immunoglobulin light concentration for selection of specimens for immunofixation electrophoresis. METHODS: Using kits from The Binding Site for Freelite ®, we validated examination of urine for measuring free κ and λ light chains. The results of urine free light chain concentrations were evaluated to ascertain if the results could be used to reduce the number of specimens requiring urine protein immunofixation electrophoresis. RESULTS: In the 515 specimens examined, there was no evidence of monoclonal gammopathy or history of monoclonal gammopathy in 331. Monoclonal κ or λ light chains were detectable in 42 and 30 specimens, respectively. There was history of κ or λ chain associated monoclonal gammopathy in 62 and 50 patients, respectively. In the 38 monoclonal κ positive urine specimens, with light chain data, κ/λ ratio was >5.83 in all specimens. In 27 specimens positive for monoclonal λ light chains, with light chain data, the urine λ/κ ratio was > 0.17 in 24 of 27 specimens and > 0.041 in all specimens. In patients without monoclonal gammopathy all specimens had a κ/λ ratio of >5.83 or λ/κ ratio >0.17. CONCLUSIONS: The Freelite ® assay from The Binding Site is suitable for quantification of free light chains in urine. In patients with known history of monoclonal gammopathy, urine immunofixation electrophoresis may be omitted in specimens with κ/λ ratio of <5.83 for κ associated lesions and λ/κ ratio of <0.041 for λ associated lesions. However, the results do not support using this test for first-time urine testing for monoclonal light chains as it is not predictive of positive result, nor does it exclude a monoclonal light chain in urine.


Asunto(s)
Gammopatía Monoclonal de Relevancia Indeterminada , Paraproteinemias , Humanos , Cadenas Ligeras de Inmunoglobulina/orina , Paraproteinemias/diagnóstico , Cadenas lambda de Inmunoglobulina , Electroforesis/métodos
4.
Front Immunol ; 14: 1212209, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37435071

RESUMEN

The cell surface enzyme CD73 is increasingly appreciated as a pivotal non-redundant immune checkpoint (IC) in addition to PD-1/PD-L1 and CTLA-4. CD73 produces extracellular adenosine (eADO), which not only inhibits antitumor T cell activity via the adenosine receptor (AR) A2AR, but also enhances the immune inhibitory function of cancer-associated fibroblasts and myeloid cells via A2BR. Preclinical studies show that inhibition of the CD73-adenosinergic pathway in experimental models of many solid tumors either as a monotherapy or, more effectively, in combination with PD-1/PD-L1 or CTLA-4 IC blockades, improves antitumor immunity and tumor control. Consequently, approximately 50 ongoing phase I/II clinical trials targeting the CD73-adenosinergic IC are currently listed on https://clinicaltrials.gov. Most of the listed trials employ CD73 inhibitors or anti-CD73 antibodies alone, in combination with A2AR antagonists, and/or with PD-1/PD-L1 blockade. Recent evidence suggests that the distribution of CD73, A2AR and A2BR in tumor microenvironments (TME) is heterogeneous, and this distribution affects CD73-adenosinergic IC function. The new insights have implications for the optimally effective, carefully tailored approaches to therapeutic targeting of this essential IC. In the mini-review, we briefly discuss the cellular and molecular mechanisms of CD73/eADO-mediated immunosuppression during tumor progression and therapy in the spatial context of the TME. We include preclinical data regarding therapeutic CD73-eADO blockade in tumor models as well as available clinical data from completed trials that targeted CD73-adenosinergic IC with or without PD-1/PD-L1 inhibitors and discuss factors that are potentially important for optimal therapeutic outcomes in cancer patients.


Asunto(s)
Antiinfecciosos , Neoplasias , Surfactantes Pulmonares , Humanos , Antígeno B7-H1 , Antígeno CTLA-4 , Receptor de Muerte Celular Programada 1 , Penicilinas , Inmunoterapia , Neoplasias/tratamiento farmacológico , Fibrinolíticos , Anestésicos Locales , Microambiente Tumoral
5.
Lab Med ; 54(5): 527-533, 2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-36857478

RESUMEN

BACKGROUND: Immunoglobulin monoclonal light chains (MLCs) in serum and urine are markers for monoclonal gammopathy and could serve as markers of minimal residual disease (MRD) in multiple myeloma (MM). Excretion of MLCs in urine is known to result in renal damage and shorter survival in patients with LC-predominant MM. METHODS: Retrospective review of urine immunofixation in 1738 specimens at 3 medical centers was conducted to assess the utility of urinalysis for diagnosis and monitoring of monoclonal gammopathy. We tested 228 stored urine specimens via the modified urine immunofixation method, using antisera to assay free LCs (FLCs). RESULTS: Our review of urine immunofixation results and medical records validated the theory that the only meaningful value-added finding was detection of monoclonal free light chains. Examination of 228 urine specimens using our novel method revealed 18.4% additional positive results. The rate of incremental findings for lambda LCs was nearly 3-fold higher than for kappa LCs. CONCLUSIONS: The new method of urine immunofixation is significantly more sensitive and more efficient than the conventional method for detecting MLCs in urine. The new assay appears to be sensitive enough to prove that MLCs serve as a marker of MRD in MM.


Asunto(s)
Gammopatía Monoclonal de Relevancia Indeterminada , Mieloma Múltiple , Paraproteinemias , Humanos , Neoplasia Residual/diagnóstico , Cadenas Ligeras de Inmunoglobulina , Electroforesis , Paraproteinemias/diagnóstico , Mieloma Múltiple/diagnóstico , Urinálisis , Cadenas lambda de Inmunoglobulina
6.
Arch Pathol Lab Med ; 147(11): 1340-1343, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36602893

RESUMEN

CONTEXT.­: Pathology training is focused on the attainment of clinical, diagnostic, and administrative skills. Preparation for employment search and the interview process are often neglected. Given that a near majority of pathology trainees in the United States are graduates of foreign medical schools, training in the job search and interview process according to local customs, norms, and expectations has greater salience for individuals new to the United States. OBJECTIVE.­: To offer perspectives on 2 components of the job search process: (1) finding a suitable job opening in academic and private practice settings and (2) preparing for an interview. We have provided a set of common interview questions and suggested preparatory methodology. The differences in the process and expectations in academic settings and private practice operations are highlighted. Engaging in the job search process early and networking are emphasized. We have also suggested approaches for pathology teachers and mentors in guiding trainees in a job search and preparation for an interview. DATA SOURCES.­: The information and opinions expressed in this communication are based on the personal experiences of 4 senior pathologists in academic and private practice settings. CONCLUSIONS.­: Start networking early. Leverage contacts with teachers, attending pathologists, senior residents, and people at national meetings to locate appropriate job opportunities. Seek assistance from attending pathologists in preparing a curriculum vitae and cover letter. Prepare for the questions that may come up in an interview. A dress rehearsal for an interview is strongly recommended.

7.
J Appl Lab Med ; 7(6): 1290-1301, 2022 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-36006797

RESUMEN

BACKGROUND: Levels of free immunoglobulin light chains in serum and urine are a sensitive measure of dysregulated immunoglobulin synthesis. The development of an assay for free light chains in serum was a major advance in laboratory testing for monoclonal gammopathies. The original assay by The Binding Site, called Freelite®, has been in common use in laboratory monitoring of monoclonal gammopathies. Two clinical entities, myeloma-defining condition and light chain-predominant multiple myeloma, rely on quantitative measurements of serum free light chains. METHODS: Using polyclonal antisera specific to free light chains, Diazyme Laboratories developed a latex immunoturbidimetric assay for quantification of human kappa and lambda serum free light chains. We evaluated the Diazyme assay by comparing the results of kappa and lambda free light chain quantification, and kappa/lambda ratio with the results on the same specimens by the Freelite method. We also compared the correlation of the 2 methods to evaluate response to treatment and to changes in clinical status of patients with multiple myeloma. RESULTS: The results of Freelite and Diazyme methods are comparable. There was no statistically significant difference in the performance of the 2 assays for quantification of light chains, kappa/lambda ratio, or correlation of clinical parameters from patients with multiple myeloma at various stages of monitoring the disease in 2 geographically diverse laboratory and clinical environments. CONCLUSIONS: The Diazyme method is comparable to Freelite and provides an opportunity to add the test to front-end automation and improvement in efficiency of the assay.


Asunto(s)
Mieloma Múltiple , Paraproteinemias , Humanos , Cadenas kappa de Inmunoglobulina , Mieloma Múltiple/diagnóstico , Cadenas Ligeras de Inmunoglobulina , Cadenas lambda de Inmunoglobulina , Paraproteinemias/diagnóstico
8.
J Immunother Cancer ; 10(7)2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35882449

RESUMEN

BACKGROUND: Adoptive cell therapy (ACT) using genetically modified T cells has evolved into a promising treatment option for patients with cancer. However, even for the best-studied and clinically validated CD19-targeted chimeric antigen receptor (CAR) T-cell therapy, many patients face the challenge of lack of response or occurrence of relapse. There is increasing need to improve the efficacy of ACT so that durable, curative outcomes can be achieved in a broad patient population. METHODS: Here, we investigated the impact of indomethacin (indo), a non-steroidal anti-inflammatory drug (NSAID), on the efficacy of ACT in multiple preclinical models. Mice with established B-cell lymphoma received various combinations of preconditioning chemotherapy, infusion of suboptimal dose of tumor-reactive T cells, and indo administration. Donor T cells used in the ACT models included CD4+ T cells expressing a tumor-specific T cell receptor (TCR) and T cells engineered to express CD19CAR. Mice were monitored for tumor growth and survival. The effects of indo on donor T cell phenotype and function were evaluated. The molecular mechanisms by which indo may influence the outcome of ACT were investigated. RESULTS: ACT coupled with indo administration led to improved tumor growth control and prolonged mouse survival. Indo did not affect the activation status and tumor infiltration of the donor T cells. Moreover, the beneficial effect of indo in ACT did not rely on its inhibitory effect on the immunosuppressive cyclooxygenase 2 (COX2)/prostaglandin E2 (PGE2) axis. Instead, indo-induced oxidative stress boosted the expression of death receptor 5 (DR5) in tumor cells, rendering them susceptible to donor T cells expressing TNF-related apoptosis-inducing ligand (TRAIL). Furthermore, the ACT-potentiating effect of indo was diminished against DR5-deficient tumors, but was amplified by donor T cells engineered to overexpress TRAIL. CONCLUSION: Our results demonstrate that the pro-oxidative property of indo can be exploited to enhance death receptor signaling in cancer cells, providing rationale for combining indo with genetically modified T cells to intensify tumor cell killing through the TRAIL-DR5 axis. These findings implicate indo administration, and potentially similar use of other NSAIDs, as a readily applicable and cost-effective approach to augment the efficacy of ACT.


Asunto(s)
Indometacina , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF , Animales , Antiinflamatorios no Esteroideos/farmacología , Tratamiento Basado en Trasplante de Células y Tejidos , Humanos , Indometacina/farmacología , Ratones , Recurrencia Local de Neoplasia , Estrés Oxidativo , Ligando Inductor de Apoptosis Relacionado con TNF
9.
Metabolites ; 12(6)2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35736477

RESUMEN

Bladder Cancer (BLCA) is the ninth most frequently diagnosed cancer globally and the sixth most common cancer in the US. African Americans (AA) exhibit half the BLCA incidence compared to European Americans (EA), but they have a 70% higher risk of cancer-related death; unfortunately, this disparity in BLCA mortality remains poorly understood. In this study, we have used an ethnicity-balanced cohort for unbiased lipidomics profiling to study the changes in the lipid fingerprint for AA and EA BLCA tissues collected from similar geographical regions to determine a signature of ethnic-specific alterations. We identified 86 lipids significantly altered between self-reported AA and EA BLCA patients from Augusta University (AU) cohort. The majority of altered lipids belong to phosphatidylcholines (PCs), phosphatidylethanolamines (PEs), ly sophosphatidylcholines (lysoPCs), phosphatidylserines (PSs), and diglycerides (DGs). Interestingly, levels of four lysoPCs (lyso PCs 20:3, lyso PCs 22:1, lyso PCs 22:2, and lyso PCs 26:1) were elevated while, in contrast, the majority of the PCs were reduced in AA BLCA. Significant alterations in long-chain monounsaturated (MonoUN) and polyunsaturated (PolyUN) lipids were also observed between AA and EA BLCA tumor tissues. These first-in-field results implicate ethnic-specific lipid alterations in BLCA.

10.
Lab Med ; 53(2): 145-148, 2022 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-34388245

RESUMEN

OBJECTIVE: Patients with light chain-predominant multiple myeloma have been shown to exhibit shorter survival. Retrospective comparison of clinical and laboratory data was undertaken to ascertain the likely cause(s) of this observation. METHODS: Records of patients with multiple myeloma seen at 1 institution revealed 316 patients with conventional and 71 patients with light chain-predominant multiple myelomas with secretion of intact immunoglobulins. Laboratory and clinical findings in the 2 groups were compared. RESULTS: Patients with light chain-predominant multiple myeloma had a significantly higher death rate, a higher rate of chronic dialysis, a lower estimated glomerular filtration rate and serum albumin, a significantly higher urine protein concentration, and a significantly higher prevalence of hypertension and blood transfusion requirements. Other clinical and laboratory parameters surveyed were not significantly different between the 2 groups. CONCLUSION: The shorter survival of patients with light chain-predominant multiple myeloma is clearly associated with renal damage caused by excess free immunoglobulin light chains. Renal damage may be ameliorated by early aggressive treatment with chemotherapy, plasmapheresis, and dialysis; a multi-institutional prospective controlled trial would be needed to test this hypothesis.


Asunto(s)
Mieloma Múltiple , Insuficiencia Renal , Humanos , Cadenas Ligeras de Inmunoglobulina , Riñón/fisiopatología , Mieloma Múltiple/complicaciones , Mieloma Múltiple/mortalidad , Mieloma Múltiple/terapia , Estudios Prospectivos , Insuficiencia Renal/complicaciones , Estudios Retrospectivos , Tasa de Supervivencia
11.
Pract Lab Med ; 27: e00256, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34703870

RESUMEN

INTRODUCTION: Neoplastic monoclonal gammopathies are frequently associated with production of excess free monoclonal light chains. A sensitive method for detecting free monoclonal light chains in serum could provide a marker for residual/minimal residual disease and as an adjunct to serum protein electrophoresis to serve as a screening method for monoclonal gammopathies. METHODS: Conventional serum immunofixation electrophoresis was modified by applying undiluted serum samples, and staining for serum free light chains with antisera specific to free light chains. Washing/blotting of gels was enhanced to remove residual proteins that did not bind to the antibodies including intact monoclonal immunoglobulins. Results from this modified immunofixation electrophoresis were compared with results from commercially available MASS-FIX/MALDI assay. RESULTS: Monoclonal free kappa light chains could be detected to a concentration of about 1.78 mg/L and monoclonal free lambda light chains to a concentration of about 1.15 mg/L without the need for special equipment. Comparison of these thresholds with parallel results from a commercially available MASS-FIX/MALDI assay revealed the modified electrophoretic method to be more sensitive in the context of free monoclonal light chains. CONCLUSIONS: Modified serum immunofixation electrophoresis has been shown to detect low levels of monoclonal free light chains at a sensitivity suitable for the method to be used in detecting minimal residual disease, and potentially in a screening assay for monoclonal gammopathies. The disparity in the results with commercially available MASS-FIX/MALDI assay is postulated to be due to limited repertoire of reactivity of nanobodies of camelid origin.

12.
Immunity ; 54(10): 2354-2371.e8, 2021 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-34614413

RESUMEN

Monocytic-lineage inflammatory Ly6c+CD103+ dendritic cells (DCs) promote antitumor immunity, but these DCs are infrequent in tumors, even upon chemotherapy. Here, we examined how targeting pathways that inhibit the differentiation of inflammatory myeloid cells affect antitumor immunity. Pharmacologic inhibition of Bruton's tyrosine kinase (BTK) and the tryptophan-degrading enzyme indoleamine 2,3-dioxygenase (IDO) or deletion of Btk or Ido1 allowed robust differentiation of inflammatory Ly6c+CD103+ DCs during chemotherapy, promoting antitumor T cell responses and inhibiting tumor growth. Immature Ly6c+c-kit+ precursor cells had epigenetic profiles similar to conventional DC precursors; deletion of Btk or Ido1 promoted differentiation of these cells. Mechanistically, a BTK-IDO axis inhibited a tryptophan-sensitive differentiation pathway driven by GATOR2 and mTORC1, and disruption of the GATOR2 in monocyte-lineage precursors prevented differentiation into inflammatory DCs in vivo. IDO-expressing DCs and monocytic cells were present across a range of human tumors. Thus, a BTK-IDO axis represses differentiation of inflammatory DCs during chemotherapy, with implications for targeted therapies.


Asunto(s)
Diferenciación Celular/inmunología , Células Dendríticas/inmunología , Neoplasias/inmunología , Linfocitos T/inmunología , Agammaglobulinemia Tirosina Quinasa/inmunología , Agammaglobulinemia Tirosina Quinasa/metabolismo , Animales , Células Dendríticas/citología , Células Dendríticas/metabolismo , Femenino , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/inmunología , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Masculino , Ratones , Monocitos/citología , Monocitos/inmunología , Monocitos/metabolismo , Transducción de Señal/inmunología , Linfocitos T/metabolismo , Serina-Treonina Quinasas TOR/inmunología , Serina-Treonina Quinasas TOR/metabolismo
13.
J Appl Lab Med ; 6(6): 1592-1600, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34468749

RESUMEN

BACKGROUND: Monoclonal immunoglobulins provide an indication of the tumor burden in patients with plasma cell neoplasms. Higher concentrations of serum free light chains in light chain predominant multiple myeloma have been shown to correlate with a poorer outcome. We examined the correlations of serum free light chain concentrations in light chain myelomas with survival, estimated glomerular filtration rate (eGFR) and other clinical and pathological parameters. METHODS: Records of patients with light chain multiple myelomas were reviewed. Highest concentration of serum free light chains for each patient were plotted to ascertain an inflection/change point. Survival, eGFR, and other clinical and pathological parameters were compared between the low and high light chain concentration groups. RESULTS: Plotting serum free light chain concentrations revealed an inflection point at a concentration of 455 mg/L apportioning patients in to 2 subgroups: 39 patients with low light chain concentrations and 26 patients with high concentrations. The high concentration group had more unfavorable pathology in bone marrow examination in terms of higher neoplastic plasma cell burden and high-risk cytogenetics. The survival rate and eGFR in the high concentration group were significantly worse than in the low concentration group. CONCLUSIONS: As noted for light chain predominant multiple myeloma, high serum free light chain concentration in light chain multiple myelomas are associated with higher renal disease burden and shorter survival. Monitoring of serum free light chain concentrations and customizing treatments to address this parameter are warranted.


Asunto(s)
Enfermedades Renales , Mieloma Múltiple , Anticuerpos Monoclonales , Humanos , Cadenas Ligeras de Inmunoglobulina , Riñón , Mieloma Múltiple/diagnóstico
14.
Pract Lab Med ; 26: e00240, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34124325

RESUMEN

Heavy chain isotypes of low level monoclonal immunoglobulins are sometimes obscured in serum immunofixation electrophoresis (SIFE) by a heavy background of polyclonal immunoglobulins. However, accurate determination of the heavy chain isotype is essential for a complete diagnosis, as isotype determination of autoantibodies may have relevance in determining therapeutic procedures. Immune subtraction (IS) was employed in a patient with neuropathy and GD1a autoantibody. IS allowed identification of the cognate heavy chain related to a lambda light chain restriction noted on initial SIFE as well as isotype determination of the autoantibody. Antisera specific to individual heavy and light chains were used for depletion of specific immunoglobulin types. Depletion of kappa light chain associated immunoglobulins allowed unequivocal determination of the isotype of lambda light chain-associated low level monoclonal band to be IgG Lambda. Selective depletion of kappa, lambda, gamma and mu heavy chain immunoglobulins was employed to determine IgG Kappa isotype of the auto-antibody.

15.
Nat Commun ; 12(1): 3573, 2021 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-34117223

RESUMEN

O-GalNAc glycans (or mucin O-glycans) play pivotal roles in diverse biological and pathological processes, including tumor growth and progression. Structurally defined O-GalNAc glycans are essential for functional studies but synthetic challenges and their inherent structural diversity and complexity have limited access to these compounds. Herein, we report an efficient and robust chemoenzymatic modular assembly (CEMA) strategy to construct structurally diverse O-GalNAc glycans. The key to this strategy is the convergent assembly of O-GalNAc cores 1-4 and 6 from three chemical building blocks, followed by enzymatic diversification of the cores by 13 well-tailored enzyme modules. A total of 83 O-GalNAc glycans presenting various natural glycan epitopes are obtained and used to generate a unique synthetic mucin O-glycan microarray. Binding specificities of glycan-binding proteins (GBPs) including plant lectins and selected anti-glycan antibodies towards these O-GalNAc glycans are revealed by this microarray, promoting their applicability in functional O-glycomics. Serum samples from colorectal cancer patients and healthy controls are assayed using the array reveal higher bindings towards less common cores 3, 4, and 6 than abundant cores 1 and 2, providing insights into O-GalNAc glycan structure-activity relationships.


Asunto(s)
Glicómica , Mucinas/química , Mucinas/metabolismo , Polisacáridos/química , Polisacáridos/metabolismo , Carbohidratos , Proteínas Portadoras/metabolismo , Epítopos , Glicosilación , Humanos , Análisis por Micromatrices
16.
J Appl Lab Med ; 6(2): 522-531, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33674880

RESUMEN

BACKGROUND: Pathology residents are thought to show a lack of interest in clinical chemistry, therefore potentially graduating from training programs unprepared to function as laboratory directors and clinical consultants. METHODS: A structured program of tutorials based primarily on Henry's textbook, supplemented by recent review articles; a question bank of about 600 questions to emphasize key concepts; requirement for performing and presenting quality improvement projects; participation in on-site CAP inspections; review of reference laboratory test requests; and involving residents in scholarly activity have resulted in sustained, transferable, and significant improvements in engagement, knowledge, competence, and examination scores. RESULTS: The primary parameter for measuring change in resident competence and engagement were improvements in resident in-service examination (RISE) scores, publications in peer-reviewed journals, and receipt of awards. The revised program produced significant improvement in RISE scores in clinical chemistry, over and above the improvements in the general residency program. The residents were authors on 12 publications in peer-reviewed PubMed listed journals in the 5-year period since revision in the clinical chemistry curriculum compared to no publications in clinical chemistry in the 5-year period before the new curriculum. Over the past 2 years, 6 of the 11 publications by graduating residents were in clinical chemistry, and 6 of 7 awards for research were garnered by residents engaged in clinical chemistry investigations. All of the residents passed their clinical pathology boards on first attempt since the change compared to 2 failures in the prior 5-year period. CONCLUSIONS: The structured program described here is important as a template that could be adopted by any pathology training program. The question bank developed by this program is a valuable and transferable aid. However, success of such a program is dependent on the commitment of a knowledgeable, dedicated, and passionate teacher.


Asunto(s)
Investigación Biomédica , Internado y Residencia , Química Clínica , Curriculum , Humanos , Mejoramiento de la Calidad
18.
Anal Chem ; 93(10): 4449-4455, 2021 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-33630567

RESUMEN

Absolute glycoproteomics quantification has drawn tremendous attention owing to its prospects in biomarker discovery and clinical implementation but is impeded by a general lack of suitable heavy isotope-labeled glycopeptide standards. In this study, we devised a facile chemoenzymatic strategy to synthesize a total of 36 human IgG glycopeptides attached with well-defined glycoforms, including 15 isotope-labeled ones with a mass increment of 6 Da to their native counterparts. Spiking of these standards into human sera enabled simplified, robust, and precise absolute quantification of IgG glycopeptides in a subclass-specific fashion. Additionally, the implementation of the absolute quantification approach revealed subclass-dependent alteration of serum IgG galactosylation and sialylation in colon cancer samples.


Asunto(s)
Glicopéptidos , Inmunoglobulina G , Glicosilación , Humanos , Isótopos
19.
Cancers (Basel) ; 13(3)2021 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-33503830

RESUMEN

Gene expression profiling has been shown to be comparable to other molecular methods for glioma classification. We sought to validate a gene-expression based glioma classification method. Formalin-fixed paraffin embedded tissue and flash frozen tissue collected at the Augusta University (AU) Pathology Department between 2000-2019 were identified and 2 mm cores were taken. The RNA was extracted from these cores after deparaffinization and bead homogenization. One hundred sixty-eight genes were evaluated in the RNA samples on the nCounter instrument. Forty-eight gliomas were classified using a supervised learning algorithm trained by using data from The Cancer Genome Atlas. An ensemble of 1000 linear support vector models classified 30 glioma samples into TP1 with classification confidence of 0.99. Glioma patients in TP1 group have a poorer survival (HR (95% CI) = 4.5 (1.3-15.4), p = 0.005) with median survival time of 12.1 months, compared to non-TP1 groups. Network analysis revealed that cell cycle genes play an important role in distinguishing TP1 from non-TP1 cases and that these genes may play an important role in glioma survival. This could be a good clinical pipeline for molecular classification of gliomas.

20.
J Appl Lab Med ; 6(1): 304-306, 2021 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-33156913
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA