| 1. |
- Bortz, Robert H., et al.
(author)
-
Single-Dilution COVID-19 Antibody Test with Qualitative and Quantitative Readouts
- 2021
-
In: mSphere. - : American Society for Microbiology. - 2379-5042. ; 6:2
-
Journal article (peer-reviewed)abstract
- The coronavirus disease 2019 (COVID-19) global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to place an immense burden on societies and health care systems. A key component of COVID-19 control efforts is serological testing to determine the community prevalence of SARS-CoV-2 exposure and quantify individual immune responses to prior SARS-CoV-2 infection or vaccination. Here, we describe a laboratory-developed antibody test that uses readily available research-grade reagents to detect SARS-CoV-2 exposure in patient blood samples with high sensitivity and specificity. We further show that this sensitive test affords the estimation of viral spike-specific IgG titers from a single sample measurement, thereby providing a simple and scalable method to measure the strength of an individual's immune response. The accuracy, adaptability, and cost-effectiveness of this test make it an excellent option for clinical deployment in the ongoing COVID-19 pandemic.IMPORTANCE Serological surveillance has become an important public health tool during the COVID-19 pandemic. Detection of protective antibodies and seroconversion after SARS-CoV-2 infection or vaccination can help guide patient care plans and public health policies. Serology tests can detect antibodies against past infections; consequently, they can help overcome the shortcomings of molecular tests, which can detect only active infections. This is important, especially when considering that many COVID-19 patients are asymptomatic. In this study, we describe an enzyme-linked immunosorbent assay (ELISA)-based qualitative and quantitative serology test developed to measure IgG and IgA antibodies against the SARS-CoV-2 spike glycoprotein. The test can be deployed using commonly available laboratory reagents and equipment and displays high specificity and sensitivity. Furthermore, we demonstrate that IgG titers in patient samples can be estimated from a single measurement, enabling the assay's use in high-throughput clinical environments.
|
|
| 2. |
- Kerkman, Priscilla, et al.
(author)
-
Generation of plasma cells and CD27-IgD- B cells during hantavirus infection is associated with distinct pathological findings
- 2021
-
In: Clinical & Translational Immunology (CTI). - : John Wiley & Sons. - 2050-0068. ; 10
-
Journal article (peer-reviewed)abstract
- Objective: Human hantavirus infections can cause haemorrhagic fever with renal syndrome (HFRS). The pathogenic mechanisms arenot fully understood, nor if they affect the humoral immune system. The objective of this study was to investigate humoral immune responses to hantavirus infection and to correlate them to the typical features of HFRS: thrombocytopenia and transient kidney dysfunction.Methods: We performed a comprehensive characterisation of longitudinal antiviral B-cell responses of 26 hantavirus patients and combined this with paired clinical data. In addition, we measured extracellular adenosine triphosphate (ATP)and its breakdown products in circulation and performed in vitro stimulations to address its effect on B cells.Results: We found that thrombocytopenia was correlated to an elevated frequency of plasmablasts in circulation. In contrast, kidney dysfunction was indicative of an accumulation of CD27-IgD- B cells and CD27/low plasmablasts. Finally, we provide evidence that high levels of extracellular ATP and matrix metalloproteinase 8 can contribute to shedding of CD27 during human hantavirus infection.Conclusion: Our findings demonstrate that thrombocytopenia and kidneydysfunction associate with distinctly different effects on the humoral immune system. Moreover, hantavirus-infectedindividuals have significantly elevated levels of extracellular ATP incirculation.
|
|
| 3. |
|
|
| 4. |
- Mittler, Eva, et al.
(author)
-
Human antibody recognizing a quaternary epitope in the Puumala virus glycoprotein provides broad protection against orthohantaviruses
- 2022
-
In: Science Translational Medicine. - : American Association for the Advancement of Science. - 1946-6234 .- 1946-6242. ; 14:636
-
Journal article (peer-reviewed)abstract
- The rodent-borne hantavirus Puumala virus (PUUV) and related agents cause hemorrhagic fever with renal syndrome (HFRS) in humans. Other hantaviruses, including Andes virus (ANDV) and Sin Nombre virus, cause a distinct zoonotic disease, hantavirus cardiopulmonary syndrome (HCPS). Although these infections are severe and have substantial case fatality rates, no FDA-approved hantavirus countermeasures are available. Recent work suggests that monoclonal antibodies may have therapeutic utility. We describe here the isolation of human neutralizing antibodies (nAbs) against tetrameric Gn/Gc glycoprotein spikes from PUUV-experienced donors. We define a dominant class of nAbs recognizing the "capping loop" of Gn that masks the hydrophobic fusion loops in Gc. A subset of nAbs in this class, including ADI-42898, bound Gn/Gc complexes but not Gn alone, strongly suggesting that they recognize a quaternary epitope encompassing both Gn and Gc. ADI-42898 blocked the cell entry of seven HCPS- and HFRS-associated hantaviruses, and single doses of this nAb could protect Syrian hamsters and bank voles challenged with the highly virulent HCPS-causing ANDV and HFRS-causing PUUV, respectively. ADI-42898 is a promising candidate for clinical development as a countermeasure for both HCPS and HFRS, and its mode of Gn/Gc recognition informs the development of broadly protective hantavirus vaccines.
|
|
| 5. |
- Mittler, Eva, et al.
(author)
-
Structural and mechanistic basis of neutralization by a pan-hantavirus protective antibody
- 2023
-
In: Science Translational Medicine. - : American Association for the Advancement of Science (AAAS). - 1946-6234 .- 1946-6242. ; 15:700
-
Journal article (peer-reviewed)abstract
- Emerging rodent-borne hantaviruses cause severe diseases in humans with no approved vaccines or therapeutics. We recently isolated a monoclonal broadly neutralizing antibody (nAb) from a Puumala virus-experienced human donor. Here, we report its structure bound to its target, the Gn/Gc glycoprotein heterodimer comprising the viral fusion complex. The structure explains the broad activity of the nAb: It recognizes conserved Gc fusion loop sequences and the main chain of variable Gn sequences, thereby straddling the Gn/Gc heterodimer and locking it in its prefusion conformation. We show that the nAb's accelerated dissociation from the divergent Andes virus Gn/Gc at endosomal acidic pH limits its potency against this highly lethal virus and correct this liability by engineering an optimized variant that sets a benchmark as a candidate pan-hantavirus therapeutic.
|
|
| 6. |
- Wec, Anna Z., et al.
(author)
-
Longitudinal dynamics of the human B cell response to the yellow fever 17D vaccine
- 2020
-
In: Proceedings of the National Academy of Sciences of the United States of America. - Washington : National Academy of Science. - 0027-8424 .- 1091-6490. ; 117:12, s. 6675-6685
-
Journal article (peer-reviewed)abstract
- A comprehensive understanding of the development and evolution of human B cell responses duced by pathogen exposure will facilitate the design of next-generation vaccines. Here, we utilized a gh-throughput single B cell cloning technology to longitudinally track the human B cell response to the llow fever virus 17D (YFV-17D) vaccine. The earlymemory B cell (MBC) response was mediated by both assical immunoglobulin M (IgM) (IgM(+)CD27(+)) and switched immunoglobulin (swIg(+)) MBC pulations; however, classical IgM MBCs waned rapidly, whereas swIg(+) and atypical IgM(+) and IgD(+) MBCs were stable over time. Affinity maturation continued for 6 to 9 mo following vaccination, providing evidence for the persistence of germinal center activity long after the period of active viral replication in peripheral blood. Finally, a substantial fraction of the neutralizing antibody response was mediated by public clones that recognize a fusion loop-proximal antigenic site within domain II of the viral envelope glycoprotein. Overall, our findings provide a framework for understanding the dynamics and complexity of human B cell responses elicited by infection and vaccination.
|
|
