1. |
- Piao, H. L., et al.
(author)
-
Affinity-matured recombinant immunotoxin targeting gangliosides 3 '-isoLM1 and 3 ', 6 '-isoLD1 on malignant gliomas
- 2013
-
In: Mabs. - : Informa UK Limited. - 1942-0862 .- 1942-0870. ; 5:5, s. 748-762
-
Journal article (peer-reviewed)abstract
- About 60 percent of glioblastomas highly express the gangliosides 3-isoLM1 and 3,6-isoLD1 on the cell surface, providing ideal targets for brain tumor immunotherapy. A novel recombinant immunotoxin, DmAb14m-(scFv)-PE38KDEL (DmAb14m-IT), specific for the gangliosides 3-isoLM1 and 3,6-isoLD1, was constructed with improved affinity and increased cytotoxicity for immunotherapeutic targeting of glioblastoma. We isolated an scFv parental clone from a previously established murine hybridoma, DmAb14, that is specific to both 3-isoLM1 and 3,6-isoLD1. We then performed in vitro affinity maturation by CDR hotspot random mutagenesis. The binding affinity and specificity of affinity-matured DmAb14m-IT were measured by surface-plasmon resonance, flow cytometry, and immunohistochemical analysis. In vitro cytotoxicity of DmAb14m-IT was measured by protein synthesis inhibition and cell death assays in human cell lines expressing gangliosides 3-isoLM1 and 3,6-isoLD1 (D54MG and D336MG) and xenograft-derived cells (D2224MG). As a result, the K-D of DmAb14m-IT for gangliosides 3-isoLM1 and 3,6-isoLD1 was 2.6 x 10(-9)M. Also, DmAb14m-IT showed a significantly higher internalization rate in cells expressing 3-isoLM1 and 3,6-isoLD1. The DmAb14m-IT IC50 was 80 ng/mL (1194 pM) on the D54MG cell line, 5 ng/ml (75 pM) on the D336MG cell line, and 0.5 ng/ml (7.5 pM) on the D2224MG xenograft-derived cells. There was no cytotoxicity on ganglioside-negative HEK293 cells. Immunohistochemical analysis confirmed the specific apparent affinity of DmAb14m-IT with 3-isoLM1 and 3,6-isoLD1. In conclusion, DmAb14m-IT showed specific binding affinity, a significantly high internalization rate, and selective cytotoxicity on glioma cell lines and xenograft-derived cells expressing 3-isoLM1 and 3,6-isoLD1, thereby displaying robust therapeutic potential for testing the antitumor efficacy of DmAb14m-IT at the preclinical level and eventually in the clinical setting.
|
|
2. |
|
|
3. |
- de Savigny, Don, et al.
(author)
-
Integrating community-based verbal autopsy into civil registration and vital statistics (CRVS) : system-level considerations
- 2017
-
In: Global Health Action. - : Informa UK Limited. - 1654-9716 .- 1654-9880. ; 10
-
Journal article (peer-reviewed)abstract
- Background: Reliable and representative cause of death (COD) statistics are essential to inform public health policy, respond to emerging health needs, and document progress towards Sustainable Development Goals. However, less than one-third of deaths worldwide are assigned a cause. Civil registration and vital statistics (CRVS) systems in low-and lowermiddle-income countries are failing to provide timely, complete and accurate vital statistics, and it will still be some time before they can provide physician-certified COD for every death.Proposals: Verbal autopsy (VA) is a method to ascertain the probable COD and, although imperfect, it is the best alternative in the absence of medical certification. There is extensive experience with VA in research settings but only a few examples of its use on a large scale. Data collection using electronic questionnaires on mobile devices and computer algorithms to analyse responses and estimate probable COD have increased the potential for VA to be routinely applied in CRVS systems. However, a number of CRVS and health system integration issues should be considered in planning, piloting and implementing a system-wide intervention such as VA. These include addressing the multiplicity of stakeholders and sub-systems involved, integration with existing CRVS work processes and information flows, linking VA results to civil registration records, information technology requirements and data quality assurance.Conclusions: Integrating VA within CRVS systems is not simply a technical undertaking. It will have profound system-wide effects that should be carefully considered when planning for an effective implementation. This paper identifies and discusses the major system-level issues and emerging practices, provides a planning checklist of system-level considerations and proposes an overview for how VA can be integrated into routine CRVS systems.
|
|
4. |
- Karat, Aaron S., et al.
(author)
-
Measuring mortality due to HIV-associated tuberculosis among adults in South Africa : Comparing verbal autopsy, minimally-invasive autopsy, and research data
- 2017
-
In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 12:3
-
Journal article (peer-reviewed)abstract
- Background The World Health Organization (WHO) aims to reduce tuberculosis (TB) deaths by 95% by 2035; tracking progress requires accurate measurement of TB mortality. International Classification of Diseases (ICD) codes do not differentiate between HIV-associated TB and HIV more generally. Verbal autopsy (VA) is used to estimate cause of death (CoD) patterns but has mostly been validated against a suboptimal gold standard for HIV and TB. This study, conducted among HIV-positive adults, aimed to estimate the accuracy of VA in ascertaining TB and HIV CoD when compared to a reference standard derived from a variety of clinical sources including, in some, minimally-invasive autopsy (MIA). Methods and findings Decedents were enrolled into a trial of empirical TB treatment or a cohort exploring diagnostic algorithms for TB in South Africa. The WHO 2012 instrument was used; VA CoD were assigned using physician-certified VA (PCVA), InterVA-4, and SmartVA-Analyze. Reference CoD were assigned using MIA, research, and health facility data, as available. 259 VAs were completed: 147 (57%) decedents were female; median age was 39 (interquartile range [IQR] 33-47) years and CD4 count 51 (IQR 22-102) cells/mu L. Compared to reference CoD that included MIA (n = 34), VA underestimated mortality due to HIV/AIDS (94% reference, 74% PCVA, 47% InterVA-4, and 41% SmartVA-Analyze; chance-corrected concordance [CCC] 0.71, 0.42, and 0.31, respectively) and HIV-associated TB (41% reference, 32% PCVA; CCC 0.23). For individual decedents, all VA methods agreed poorly with reference CoD that did not include MIA (n = 259; overall CCC 0.14, 0.06, and 0.15 for PCVA, InterVA-4, and SmartVA-Analyze); agreement was better at population level (cause-specific mortality fraction accuracy 0.78, 0.61, and 0.57, for the three methods, respectively). Conclusions Current VA methods underestimate mortality due to HIV-associated TB. ICD and VA methods need modifications that allow for more specific evaluation of HIV-related deaths and direct estimation of mortality due to HIV-associated TB.
|
|
5. |
- Karat, Aaron S., et al.
(author)
-
Performance of verbal autopsy methods in estimating HIV-associated mortality among adults in South Africa
- 2018
-
In: BMJ Global Health. - : BMJ Publishing Group Ltd. - 2059-7908. ; 3:4
-
Journal article (peer-reviewed)abstract
- Introduction: Verbal autopsy (VA) can be integrated into civil registration and vital statistics systems, but its accuracy in determining HIV-associated causes of death (CoD) is uncertain. We assessed the sensitivity and specificity of VA questions in determining HIV status and antiretroviral therapy (ART) initiation and compared HIV-associated mortality fractions assigned by different VA interpretation methods.Methods: Using the WHO 2012 instrument with added ART questions, VA was conducted for deaths among adults with known HIV status (356 HIV positive and 103 HIV negative) in South Africa. CoD were assigned using physician-certified VA (PCVA) and computer-coded VA (CCVA) methods and compared with documented HIV status.Results: The sensitivity of VA questions in detecting HIV status and ART initiation was 84.3% (95% CI 80 to 88) and 91.0% (95% CI 86 to 95); 283/356 (79.5%) HIV-positive individuals were assigned HIV-associated CoD by PCVA, 166 (46.6%) by InterVA-4.03, 201 (56.5%) by InterVA-5, and 80 (22.5%) and 289 (81.2%) by SmartVA-Analyze V.1.1.1 and V.1.2.1. Agreement between PCVA and older CCVA methods was poor (chance-corrected concordance [CCC] <0; cause-specific mortality fraction [CSMF] accuracy <= 56%) but better between PCVA and updated methods (CCC 0.21-0.75; CSMF accuracy 65%-98%). All methods were specific (specificity 87% to 96%) in assigning HIV-associated CoD.Conclusion: All CCVA interpretation methods underestimated the HIV-associated mortality fraction compared with PCVA; InterVA-5 and SmartVA-Analyze V. 1.2.1 performed better than earlier versions. Changes to VA methods and classification systems are needed to track progress towards targets for reducing HIV-associated mortality.
|
|
6. |
- Kato, Yukinari, et al.
(author)
-
GMab-1, a high-affinity anti-3'-isoLM1/3',6'-isoLD1 IgG monoclonal antibody, raised in lacto-series ganglioside-defective knockout mice
- 2010
-
In: Biochemical and biophysical research communications. - : Elsevier BV. - 1090-2104 .- 0006-291X. ; 391:1, s. 750-5
-
Journal article (peer-reviewed)abstract
- The lacto-series gangliosides 3'-isoLM1 and 3',6'-isoLD1 have been identified as tumor-associated antigens whose formation is initiated by the Lc3-synthase. Until now, high-affinity IgG monoclonal antibodies (mAbs) against 3'-isoLM1 and 3',6'-isoLD1, which are highly expressed in gliomas, have not been developed, although mAbs against lacto-series gangliosides are powerful tools for functional studies. We previously produced the Lc3-synthase gene beta3Gn-T5 knockout mice. In this study, we immunized beta3Gn-T5 knockout mice with 3'-isoLM1/3',6'-isoLD1 and produced the anti-3'-isoLM1/3',6'-isoLD1 mAb GMab-1, of the IgG(3) subclass, which should be useful for functional analysis of lacto-series gangliosides and for antibody-based therapy of gliomas.
|
|
7. |
|
|
8. |
- Nichols, Erin K., et al.
(author)
-
The WHO 2016 verbal autopsy instrument : An international standard suitable for automated analysis by InterVA, InSilicoVA, and Tariff 2.0
- 2018
-
In: PLoS Medicine. - : PUBLIC LIBRARY SCIENCE. - 1549-1277 .- 1549-1676. ; 15:1
-
Research review (peer-reviewed)abstract
- Background: Verbal autopsy (VA) is a practical method for determining probable causes of death at the population level in places where systems for medical certification of cause of death are weak. VA methods suitable for use in routine settings, such as civil registration and vital statistics (CRVS) systems, have developed rapidly in the last decade. These developments have been part of a growing global momentum to strengthen CRVS systems in low-income countries. With this momentum have come pressure for continued research and development of VA methods and the need for a single standard VA instrument on which multiple automated diagnostic methods can be developed.Methods and findings: In 2016, partners harmonized a WHO VA standard instrument that fully incorporates the indicators necessary to run currently available automated diagnostic algorithms. The WHO 2016 VA instrument, together with validated approaches to analyzing VA data, offers countries solutions to improving information about patterns of cause-specific mortality. This VA instrument offers the opportunity to harmonize the automated diagnostic algorithms in the future.Conclusions: Despite all improvements in design and technology, VA is only recommended where medical certification of cause of death is not possible. The method can nevertheless provide sufficient information to guide public health priorities in communities in which physician certification of deaths is largely unavailable. The WHO 2016 VA instrument, together with validated approaches to analyzing VA data, offers countries solutions to improving information about patterns of cause-specific mortality.
|
|
9. |
|
|
10. |
- Slater, HC, et al.
(author)
-
The temporal dynamics and infectiousness of subpatent Plasmodium falciparum infections in relation to parasite density
- 2019
-
In: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1, s. 1433-
-
Journal article (peer-reviewed)abstract
- Malaria infections occurring below the limit of detection of standard diagnostics are common in all endemic settings. However, key questions remain surrounding their contribution to sustaining transmission and whether they need to be detected and targeted to achieve malaria elimination. In this study we analyse a range of malaria datasets to quantify the density, detectability, course of infection and infectiousness of subpatent infections. Asymptomatically infected individuals have lower parasite densities on average in low transmission settings compared to individuals in higher transmission settings. In cohort studies, subpatent infections are found to be predictive of future periods of patent infection and in membrane feeding studies, individuals infected with subpatent asexual parasite densities are found to be approximately a third as infectious to mosquitoes as individuals with patent (asexual parasite) infection. These results indicate that subpatent infections contribute to the infectious reservoir, may be long lasting, and require more sensitive diagnostics to detect them in lower transmission settings.
|
|