Publications by authors named "Robert Carnahan"

Article Synopsis
  • The N-terminal domain (NTD) of the spike protein in coronaviruses like SARS-CoV-2 is not well understood, but some rare antibodies targeting it can neutralize the virus, indicating its potential role in immune protection.
  • A specific monoclonal antibody, COV1-65, has been identified that effectively recognizes the NTD of the SARS-CoV spike protein and demonstrated disease prevention in mice when administered before viral exposure.
  • The interaction between COV1-65 and the SARS-CoV spike protein reveals key structural details that could inform the development of effective vaccines against various sarbecoviruses.
View Article and Find Full Text PDF

Human respiratory syncytial virus (RSV) and human metapneumovirus (hMPV) are frequent drivers of morbidity and mortality in susceptible populations, most often infantile, older adults, and immunocompromised. The primary target of neutralizing antibodies is the fusion (F) glycoprotein on the surface of the RSV and hMPV virion. As a result of the structural conservation between RSV and hMPV F, three antigenic regions are known to induce cross-neutralizing responses: sites III, IV, and V.

View Article and Find Full Text PDF
Article Synopsis
  • Zika virus (ZIKV), a mosquito-borne virus, led to a global outbreak in 2016-2017 and continues to circulate at lower levels in some regions as there is no approved vaccine.
  • Researchers investigated a modified monoclonal antibody (mAb) known as ZIKV-117-LALA-YTE, which has been engineered to improve its effectiveness and longevity in the body.
  • In tests on rhesus macaques, this antibody showed complete protection against ZIKV at a very low dose, highlighting its potential as a new treatment option for the virus.
View Article and Find Full Text PDF

The sudden rise of the SARS-CoV-2 virus and the delay in the development of effective therapeutics to mitigate it made evident a need for ways to screen for compounds that can block infection and prevent further pathogenesis and spread. Yet, identifying effective drugs efficacious against viral infection and replication with minimal toxicity for the patient can be difficult. Monoclonal antibodies were shown to be effective, yet as the SARS-CoV-2 mutated, these antibodies became ineffective.

View Article and Find Full Text PDF
Article Synopsis
  • - The research focuses on developing pan-coronavirus interventions by identifying 50 antibodies from human B cells, particularly highlighting the antibody 54043-5, which binds to a common part of spike proteins in various coronaviruses.
  • - A structural analysis revealed that 54043-5 recognizes a specific, highly conserved region of the S2 subunit in SARS-CoV-2, which is critical for understanding how this antibody can potentially provide protection.
  • - Although 54043-5 does not neutralize the virus directly, it activates immune responses that help combat infections, and certain modifications to this antibody showed protective effects in mouse models of SARS-CoV-2 disease.
View Article and Find Full Text PDF

Antibodies to Ebola virus glycoprotein (EBOV GP) represent an important correlate of the vaccine efficiency and infection survival. Both neutralization and some of the Fc-mediated effects are known to contribute the protection conferred by antibodies of various epitope specificities. At the same time, the role of the complement system remains unclear.

View Article and Find Full Text PDF

Human parainfluenza virus type 3 (hPIV3) is a respiratory pathogen that can cause severe disease in older people and infants. Currently, vaccines against hPIV3 are in clinical trials but none have been approved yet. The haemagglutinin-neuraminidase (HN) and fusion (F) surface glycoproteins of hPIV3 are major antigenic determinants.

View Article and Find Full Text PDF

The COVID-19 pandemic underscored the promise of monoclonal antibody-based prophylactic and therapeutic drugs and revealed how quickly viral escape can curtail effective options. When the SARS-CoV-2 Omicron variant emerged in 2021, many antibody drug products lost potency, including Evusheld and its constituent, cilgavimab. Cilgavimab, like its progenitor COV2-2130, is a class 3 antibody that is compatible with other antibodies in combination and is challenging to replace with existing approaches.

View Article and Find Full Text PDF

Human parainfluenza virus 3 (HPIV3) is a widespread pathogen causing severe and lethal respiratory illness in at-risk populations. Effective countermeasures are in various stages of development; however, licensed therapeutic and prophylactic options are not available. The fusion glycoprotein (HPIV3 F), responsible for facilitating viral entry into host cells, is a major target of neutralizing Abs that inhibit infection.

View Article and Find Full Text PDF

Three coronaviruses have spilled over from animal reservoirs into the human population and caused deadly epidemics or pandemics. The continued emergence of coronaviruses highlights the need for pan-coronavirus interventions for effective pandemic preparedness. Here, using LIBRA-seq, we report a panel of 50 coronavirus antibodies isolated from human B cells.

View Article and Find Full Text PDF

From the beginning of the COVID-19 pandemic, children have exhibited different susceptibility to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, reinfection, and disease compared with adults. Motivated by the established significance of SARS-CoV-2-neutralizing antibodies in adults, here we characterize SARS-CoV-2-specific antibody repertoires in a young cohort of individuals aged from 5 months to 18 years old. Our results show that neutralizing antibodies in children possess similar genetic features compared to antibodies identified in adults, with multiple antibodies from children belonging to previously established public antibody clonotypes in adults.

View Article and Find Full Text PDF

Passively administered monoclonal antibodies (mAbs) given before or after viral infection can prevent or blunt disease. Here, we examine the efficacy of aerosol mAb delivery to prevent infection and disease in rhesus macaques inoculated with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant via intranasal and intratracheal routes. SARS-CoV-2 human mAbs or a human mAb directed to respiratory syncytial virus (RSV) are nebulized and delivered using positive airflow via facemask to sedated macaques pre- and post-infection.

View Article and Find Full Text PDF

The Togaviridae family, genus, Alphavirus, includes several mosquito-borne human pathogens with the potential to spread to near pandemic proportions. Most of these are zoonotic, with spillover infections of humans and domestic animals, but a few such as chikungunya virus (CHIKV) have the ability to use humans as amplification hosts for transmission in urban settings and explosive outbreaks. Most alphaviruses cause nonspecific acute febrile illness, with pathogenesis sometimes leading to either encephalitis or arthralgic manifestations with severe and chronic morbidity and occasional mortality.

View Article and Find Full Text PDF

Respiratory syncytial virus (RSV) and human metapneumovirus (hMPV) infections pose a significant health burden. Using pre-fusion conformation fusion (F) proteins, we isolated a panel of anti-F antibodies from a human donor. One antibody (RSV-199) potently cross-neutralized 8 RSV and hMPV strains by recognizing antigenic site III, which is partially conserved in RSV and hMPV F.

View Article and Find Full Text PDF

Unlabelled: Immune checkpoint blockade therapy, one of the most promising cancer immunotherapies, has shown remarkable clinical impact in multiple cancer types. Despite the recent success of immune checkpoint blockade therapy, however, the response rates in patients with cancer are limited (∼20%-40%). To improve the success of immune checkpoint blockade therapy, relevant preclinical animal models are essential for the development and testing of multiple combination approaches and strategies.

View Article and Find Full Text PDF

In vaccinology, both mRNA-based delivery of genes encoding antigens as well as nanoparticle-based vaccines have shown great promise in tackling challenging pathogens. In this issue of Cell, Hoffmann et al. combine these two approaches, harnessing the same cellular pathway hijacked by many viruses to boost immune responses to SARS-CoV-2 vaccination.

View Article and Find Full Text PDF
Article Synopsis
  • Understanding how our body fights off new viruses, like Ebola, helps us prepare for outbreaks.
  • Scientists studied special immune cells called B cells to see how they make antibodies against the Ebola virus.
  • They found 73 types of antibodies that can fight off the virus, which can help create better vaccines and treatments in the future.
View Article and Find Full Text PDF
Article Synopsis
  • Respiratory syncytial virus (RSV) significantly affects infants, making vaccination important, but assessing past RSV infections is crucial for safety in vaccine trials due to the risk of enhanced disease in RSV-naive children.
  • Researchers developed tests to differentiate immune responses between maternal antibodies and those of infants by measuring responses to RSV's pre-fusion (F) protein.
  • In a study of 102 young children, different immune response patterns were observed, showing that the developed assays could effectively distinguish between maternally transferred antibodies and those generated by prior RSV infections in infants.
View Article and Find Full Text PDF

Sosuga virus (SOSV) is a recently discovered paramyxovirus with a single known human case of disease. There has been little laboratory research on SOSV pathogenesis or immunity, and no approved therapeutics or vaccines are available. Here, we report the discovery of human mAbs from the circulating memory B cells of the only known human case and survivor of SOSV infection.

View Article and Find Full Text PDF

Despite prolific efforts to characterize the antibody response to human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV) mono-infections, the response to chronic co-infection with these two ever-evolving viruses is poorly understood. Here, we investigate the antibody repertoire of a chronically HIV-1/HCV co-infected individual using linking B cell receptor to antigen specificity through sequencing (LIBRA-seq). We identify five HIV-1/HCV cross-reactive antibodies demonstrating binding and functional cross-reactivity between HIV-1 and HCV envelope glycoproteins.

View Article and Find Full Text PDF

Dengue is a major public health threat. There are four dengue virus (DENV) serotypes; therefore, efforts are focused on developing safe and effective tetravalent DENV vaccines. While neutralizing antibodies contribute to protective immunity, there are still important gaps in understanding of immune responses elicited by dengue infection and vaccination.

View Article and Find Full Text PDF

Cytochrome (cyt ) can undergo reversible conformational changes under biologically relevant conditions. Revealing these alternative cyt conformers at the cell and tissue level is challenging. A monoclonal antibody (mAb) identifying a key conformational change in cyt was previously reported, but the hybridoma was rendered nonviable.

View Article and Find Full Text PDF

The COVID-19 pandemic underscored the promise of monoclonal antibody-based prophylactic and therapeutic drugs, but also revealed how quickly viral escape can curtail effective options. With the emergence of the SARS-CoV-2 Omicron variant in late 2021, many clinically used antibody drug products lost potency, including Evusheld and its constituent, cilgavimab. Cilgavimab, like its progenitor COV2-2130, is a class 3 antibody that is compatible with other antibodies in combination and is challenging to replace with existing approaches.

View Article and Find Full Text PDF

Human monoclonal antibodies (mAbs) that target the spike glycoprotein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) offer a promising approach for the prevention and treatment of coronavirus disease 2019 (COVID-19). Given suboptimal global vaccination rates, waning immunity in vaccinated individuals, and the emergence of SARS-CoV-2 variants of concern, the use of mAbs for COVID-19 prevention may increase and may need to be administered together with vaccines in certain settings. However, it is unknown whether administration of mAbs will affect the immunogenicity of SARS-CoV-2 vaccines.

View Article and Find Full Text PDF