Matthew S. Miller

Passive immunization is an important tool for protecting individuals with primary immune deficiencies from infectious diseases and offers a rapid response strategy for protecting vulnerable populations, particularly during the interval between pathogen emergence and vaccine deployment. Current approaches rely on intravenous delivery of IgG-enriched plasma or monoclonal antibodies, which limits accessibility, scalability, and effectiveness at mucosal surfaces, the primary entry point for respiratory viruses. Here, we tested LCTG-001, a polyclonal secretory IgA preparation derived from pooled human breast milk, to address these limitations. LCTG-001 demonstrated broad antiviral activity against clinically relevant respiratory viruses, including respiratory syncytial virus, adenovirus, and influenza A virus. LCTG-001 effectively recognized both group 1 and group 2 influenza A subtypes, including the highly pathogenic H5N1 clade 2.3.4.4b, and engaged nonneutralizing effector mechanisms such as neuraminidase inhibition and neutrophil activation. When administered intranasally, LCTG-001 conferred complete protection against influenza A challenge in both immunocompetent and antibody-deficient murine models, preventing morbidity and mortality through a transient early reduction in viral burden followed by sustained improvements in lung pathology and lung barrier integrity. These findings highlight the potential of breast milk–derived secretory IgA as a scalable, mucosa-targeted passive immunization strategy capable of addressing both endemic and emerging respiratory viral threats.

While several viral infections have been associated with amyotrophic lateral sclerosis (ALS), the mechanism(s) through which they promote disease remains elusive. Here we investigate the impact of common, acute viral infections on ALS disease onset and progression in the SOD1^G93A mouse model. A single sublethal infection prior to onset of ALS clinical signs is associated with markedly accelerated ALS disease progression characterized by rapid loss of hindlimb function. Prior infection results in gliosis in the lumbar spine and upregulation of transcriptional pathways involved in inflammatory responses, metabolic dysregulation, and muscular dysfunction. Therapeutic suppression of gliosis with an anti-inflammatory small molecule, or administration of a direct-acting antiviral, is associated with significantly improved ALS clinical signs, akin to what is observed in uninfected animals. Our study provides causal and mechanistic evidence that the immune response elicited by acute viral infections may be an important etiological factor that alters ALS disease trajectory.

The urgent need for rapid infectious disease tests that effectively combine sensitivity, specificity, speed, and ease of operation is increasingly recognized. Aptamers present a promising solution for the specific identification of infectious disease targets, such as viruses; however, the development of aptamer-based assays poses significant challenges. In the realm of electrochemical readout, these challenges stem from the difficulty of translating target capture into an electrochemical signal, particularly when large viral targets hinder the application of structure-switching aptamers or sandwich assays. In this study, we introduce the steric hindrance aptamer assay, which leverages viral capture to enhance steric hindrance between two complementary DNA strands, thereby modulating the electrochemical signal. This innovative assay achieves a limit of detection of 89 copies/mL in buffer and 1505 copies/mL in saliva for the identification of SARS-CoV-2 Omicron pseudovirus and 364 and 1704 copies/mL for detecting influenza A in buffer and saliva, respectively. Furthermore, this assay is evaluated using 20 clinical samples (10 positives and 10 negatives), successfully identifying patients infected with SARS-CoV-2 with 100% sensitivity and specificity when compared to reverse transcription quantitative polymerase chain reaction. The reported viral analysis is achieved within a timeframe of less than 1 h while maintaining high specificity against other respiratory viruses.

A major limitation of therapeutic delivery is the cold chain storage requirement. Adenoviruses (AdV) have been demonstrated to be an effective delivery vector for several indications including COVID-19 vaccines but are limited by storage and transportation conditions. Previous work has demonstrated formulation and drying of vectored vaccines with pullulan and trehalose-based (PT) films significantly improves thermostabilization. To increase the accessibility of AdV based therapeutics, we developed a vacuum based drying methodology with optimized PT excipients resulting in a shelf stable product. We demonstrate the thermostability of formulated and dried AdV at 55 ^o C for 7 weeks with less than 0.5 total log IU loss, and over 44 weeks at 37 ^o C with less than 0.25 total log IU loss. Additionally, murine vaccination with the ChAd-TriCoV/Mac vaccine showed no difference in response between fresh and aged at 37 ^o C for 44 weeks. These data demonstrate our formulation methodology’s performance, resulting in a shelf stable formulation for AdV based therapeutics.

The current COVID-19 vaccines are suboptimal against the evolving SARS-CoV-2 variants, particularly in high-risk populations. A next-generation vaccine strategy capable of effective induction of respiratory mucosal immunity remains to be clinically developed. Here, we report an open-label, multi-arm phase 1 study (NCT05094609) to evaluate a multi-antigenic COVID-19 vaccine delivered once via inhaled aerosol to the lung of intramuscular mRNA-vaccinated humans without or with prior SARS-CoV-2 infection (uninfected vs infected). Escalating doses of a human adenoviral (HuAd)-vectored or chimpanzee Ad (ChAd)-vectored vaccine are evaluated in the uninfected cohort. A selected Ad vaccine is further evaluated in the infected cohort. The safety is assessed as a primary outcome. Ag-specific immune responses (secondary outcome) are assessed in peripheral blood and in respiratory tract via bronchoscopy at baseline and at timepoint(s) post-vaccination. Eighteen-65-year-old, healthy participants who have received at least 3 doses of mRNA COVID-19 vaccine are enrolled with those vaccinated with any Ad-vectored COVID-19 vaccine excluded. At baseline, there is minimally detectable mucosal immunity in the lung of uninfected or infected humans. While all tested doses (1 × 10⁵ to 1 × 10⁸ TCID₅₀) of HuAd and ChAd vaccines are safe, ChAd vaccine markedly outperforms the HuAd counterpart in immunogenicity. Thus, an optimal aerosol dose of ChAd vaccine induces the tripartite respiratory mucosal immunity consisting of T cell, trained innate and antibody immunity. Our study thus presents a promising next-generation aerosol COVID-19 vaccine strategy for further clinical development.

Background: Common cold coronaviruses were a frequent cause of respiratory infections in older adults living in congregate care homes before the coronavirus disease 2019 pandemic, which may influence immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination and infection. We investigated humoral and cellular immune responses to prior common cold coronaviruses and SARS-CoV-2, how they are affected by SARS-CoV-2 vaccination and infection, and their associations with Omicron BA.1 SARS-CoV-2 infections in residents of long-term care and retirement homes. Methods: In SARS-CoV-2 infection–naive residents with 3 monovalent messenger RNA SARS-CoV-2 vaccinations, we measured serum anti–receptor binding domain (RBD) immunoglobulin (Ig) G and IgA antibody titers against SARS-CoV-2 and common cold human coronavirus (HCoV) NL63, HCoV-OC43, and HCoV-229E; ancestral and Omicron BA.1 neutralizing antibodies; and CD4+ and CD8+ T-cell activation responses to membrane, nucleocapsid, and spike proteins. We examined the relationships of common cold coronavirus and SARS-CoV-2 humoral immune responses, whether antibody and T-cell responses changed after SARS-CoV-2 messenger RNA vaccination or infection, and their associations with Omicron BA.1 infection. Results: Anti-RBD IgG HCoV-OC43 titers were positively correlated with SARS-CoV-2 anti-RBD IgG and neutralizing antibody titers. Common cold coronavirus anti-RBD IgA titers, but not anti-RBD IgG titers, increased after SARS-CoV-2 vaccination or infection, and many residents had cross-reactive T cells. Common cold coronavirus humoral immunity was similar in residents without and those with subsequent Omicron BA.1 infection. Conclusions: Despite frequent exposure, and associations of common cold coronavirus and vaccine-induced SARS-CoV-2 humoral immunity, preexisting common cold coronavirus immunity was not associated with Omicron BA.1 infection in residents of long-term care and retirement communities.

While several viral infections have been associated with amyotrophic lateral sclerosis (ALS), the mechanism(s) through which they promote disease has remained almost entirely elusive. This study investigated the impact of common, acute viral infections prior to disease onset on ALS progression in the SOD1G93A mouse model. A single sublethal infection prior to onset of ALS clinical signs was associated with markedly accelerated ALS disease progression characterized by rapid loss of hindlimb function. Prior infection resulted in gliosis in the lumbar spine and upregulation of transcriptional pathways involved in inflammatory responses, metabolic dysregulation, and muscular dysfunction. Therapeutic suppression of gliosis with an anti-inflammatory small molecule, or administration of a direct-acting antiviral, was associated with significantly improved ALS clinical signs, akin to what was observed in uninfected animals. This study provides causal and mechanistic evidence that the immune response elicited by acute viral infections may be an important etiological factor that alters ALS disease trajectory, and provides insight into novel therapeutic and preventative strategies for ALS.

Hemagglutinin (HA)-inhibiting antibodies contribute to the immune defense against influenza infection. However, there are insufficient data on the extent of correlation between vaccine-elicited HA antibodies and protection in children against different influenza strains, particularly when comparing live attenuated influenza vaccines (LAIV) versus inactivated influenza vaccines (IIV). We measured postvaccination hemagglutination-inhibition (HAI) titers in 3–15-year-old participants of a cluster-randomized controlled trial of trivalent LAIV(3) versus IIV(3) in Canadian Hutterite colonies. We assessed HAI titers as predictors of symptomatic, reverse transcription polymerase chain reaction (RT-PCR)-confirmed influenza over 3 influenza seasons using Cox proportional hazards regression models with vaccine type as a covariate. For each log₂ unit increase in postvaccination HAI against A/H1N1 in 2013–2014, A/H3N2 2014–2015, and B/Yamagata in 2013–2014 (each the predominant circulating strain for the respective influenza season), the reduction in the risk of confirmed influenza was equal to 29.6% (95% confidence interval [CI], 17.1%–39.5%), 34.8% (95% CI, 17.2%–47.9%), and 31.8% (95% CI, 23.8%–38.5%), respectively. No reduction in the risk of influenza was observed with B/Yamagata-specific HAI titers in 2012–2013, which was dominated by a mixture of Yamagata and Victoria strains. Despite the overall lower HAI titers in the LAIV3 group, both H1N1 and H3N2 HAI titers were associated with protection against subtype matched influenza. Both LAIV3- and IIV3-elicited HA antibodies are associated with protection against influenza infection in seasons when the vaccine strains match the circulating influenza strain subtypes, supporting the use of HAI as a correlate of protection for both vaccine types in children.

Summary: While several viral infections have been associated with amyotrophic lateral sclerosis (ALS), the mechanism(s) through which they promote disease has remained almost entirely elusive. This study investigated the impact of common, acute viral infections prior to disease onset on ALS progression in the SOD1 ^G93A mouse model. A single sublethal infection prior to onset of ALS clinical signs was associated with markedly accelerated ALS disease progression characterized by rapid loss of hindlimb function. Prior infection resulted in gliosis in the lumbar spine and upregulation of transcriptional pathways involved in inflammatory responses, metabolic dysregulation, and muscular dysfunction. Therapeutic suppression of gliosis with an anti-inflammatory small molecule, or administration of a direct-acting antiviral, was associated with significantly improved ALS clinical signs, akin to what was observed in uninfected animals. This study provides causal and mechanistic evidence that the immune response elicited by acute viral infections may be an important etiological factor that alters ALS disease trajectory, and provides insight into novel therapeutic and preventative strategies for ALS. One Sentence Summary: Acute viral infection with influenza A virus and SARS-CoV-2 accelerates the progression of ALS in SOD1 ^G93A mice.