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Carlock, M. A.

Publications and source records attributed to Carlock, M. A..

5 recordsLinked to original sources

Intranasal administration of split-inactivated influenza virus vaccine mixed with a novel adjuvant elicits protective antibodies against seasonal influenza viruses.

Seasonal influenza remains a persistent global health concern, and despite the availability of vaccines, there are both limitations in vaccine effectiveness and needle-associated hesitancy that reduce vaccine uptake. To address these challenges, this study evaluated the intranasal delivery of Fluzone, a commercially licensed split-inactivated influenza vaccine, formulated with or without adjuvant. Mice were vaccinated intranasally with Fluzone alone or combined with either Infectimune, a cationic lipid nanoparticle adjuvant, or TRAC478, a synthetic dual toll-like receptor liposome adjuvant containing TLR4 and TLR7/8 agonists. In immunologically naive mice, a higher inoculation volume was more effective at eliciting protective antibody responses even though the same dose of vaccine antigen was used for vaccination. Fluzone mixed with adjuvant enhanced hemagglutination-inhibition (HAI) titers and all mice were protected against influenza virus challenge. Mice with pre-existing anti-influenza virus immunity that was elicited by prior infection with historical influenza strains had modest antibody responses and full protection following immunization with unadjuvanted vaccine. However, the inclusion of an adjuvant with Fluzone significantly raised HAI titers and HA- specific IgG levels. Pre-immune mice vaccinated with Fluzone mixed with either adjuvant had low to undetectable viral lung titers following challenge. Overall, intranasally delivered split-inactivated influenza vaccines paired with a mucosal adjuvant is a promising strategy to enhance vaccine effectiveness.

immunology↗

Differential cross-reactivity to the influenza B virus haemagglutinin underpins lineage-specific susceptibility between birth cohorts

Influenza exposures early in life are believed to shape future susceptibility to influenza infections by imprinting immunological biases that engender differential cross-reactivity to future influenza viruses, but direct serological evidence linked to susceptibility is limited. We analysed hemagglutination-inhibition titres in 1451 cross-sectional samples collected between 1992-2020, from individuals born between 1917-2008, against influenza B virus (IBV) isolates from 1940-2021, including future isolates that circulated after sample collection. We demonstrate that immunological biases are conferred by early life IBV infection and result in lineage-specific cross-reactivity of a birth cohort towards future IBV isolates. This translates into differential estimates of susceptibility between birth cohorts towards the two IBV antigenic lineages, explaining lineage-specific age distributions of observed medically attended IBV infections. Our data bridge a critical gap between early life exposure, cross-reactivity, and influenza epidemiology and identify a plausible model to further dissect the interplay between host immunity, viral evolution and epidemiology.

immunology↗

Complex changes in serum protein levels upon recovery from SARS-CoV2 infection

The COVID-19 pandemic, triggered by severe acute respiratory syndrome coronavirus 2, has affected millions of people worldwide. Much research has been dedicated to our understanding of COVID-19 disease heterogeneity and severity, but less is known about recovery associated changes. To address this gap in knowledge, we quantified the proteome from serum samples from 29 COVID-19 convalescents and 29 age-, race-, and sex-matched healthy controls. Samples were acquired within the first months of the pandemic. Many proteins from pathways known to change during acute COVID-19 illness, such as from the complement cascade, coagulation system, inflammation and adaptive immune system, had returned to levels seen in healthy controls. In comparison, we identified 22 and 15 proteins with significantly elevated and lowered levels, respectively, amongst COVID-19 convalescents compared to healthy controls. Some of the changes were similar to those observed for the acute phase of the disease, i.e. elevated levels of proteins from hemolysis, the adaptive immune systems, and inflammation. In contrast, some alterations opposed those in the acute phase, e.g. elevated levels of CETP and APOA1 which function in lipid/cholesterol metabolism, and decreased levels of proteins from the complement cascade (e.g. C1R, C1S, and VWF), the coagulation system (e.g. THBS1 and VWF), and the regulation of the actin cytoskeleton (e.g. PFN1 and CFL1) amongst COVID-19 convalescents. We speculate that some of these shifts might originate from a transient decrease in platelet counts upon recovery from the disease. Finally, we observed race-specific changes, e.g. with respect to immunoglobulins and proteins related to cholesterol metabolism.

immunology↗

Proteomic signatures of the serological response to flu vaccination in a large human cohort study

The serological response to the influenza virus vaccine is highly heterogeneous for reasons that are not entirely clear. While the impact of demographic factors such as age, body mass index (BMI), sex, prior vaccination and titer levels are known to impact seroconversion, they only explain a fraction of the response. To identify signatures of the vaccine response, we quantified 273 proteins from serum samples of 160 flu vaccine recipients (2019-2020 season). We found that levels of proteins functioning in cholesterol transport were positively associated with seroconversion, likely linking to the known impact of BMI. When adjusting seroconversion for the demographic factors, we identified additional, unexpected signatures: proteins regulating actin cytoskeleton dynamics were significantly elevated in participants with high adjusted seroconversion. Viral strain specific analysis showed that this trend was largely driven by the H3N2 strain. Further, we identified complex associations between adjusted seroconversion and other factors: levels of proteins of the complement system associated positively with adjusted seroconversion in younger participants, while they were associated negatively in the older population. We observed the opposite trends for proteins of high density lipoprotein remodeling, transcription, and hemostasis. In sum, careful integrative modeling can extract new signatures of seroconversion from highly variable data that suggest links between the humoral response as well as immune cell communication and migration.

immunology↗

Immunisation of ferrets and mice with recombinant SARS-CoV-2 spike protein formulated with Advax-SM adjuvant protects against COVID-19 infection

The development of a safe and effective vaccine is a key requirement to overcoming the COVID-19 pandemic. Recombinant proteins represent the most reliable and safe vaccine approach but generally require a suitable adjuvant for robust and durable immunity. We used the SARS-CoV-2 genomic sequence and in silico structural modelling to design a recombinant spike protein vaccine (Covax-19). A synthetic gene encoding the spike extracellular domain (ECD) was inserted into a baculovirus backbone to express the protein in insect cell cultures. The spike ECD was formulated with Advax-SM adjuvant and first tested for immunogenicity in C57BL/6 and BALB/c mice. The Advax-SM adjuvanted vaccine induced high titers of binding antibody against spike protein that were able to neutralise the original wildtype virus on which the vaccine was based as well as the variant B.1.1.7 lineage virus. The Covax-19 vaccine also induced potent spike-specific CD4+ and CD8+ memory T-cells with a dominant Th1 phenotype, and this was shown to be associated with cytotoxic T lymphocyte killing of spike labelled target cells in vivo. Ferrets immunised with Covax-19 vaccine intramuscularly twice 2 weeks apart made spike receptor binding domain (RBD) IgG and were protected against an intranasal challenge with SARS-CoV-2 virus 2 weeks after the second immunisation. Notably, ferrets that received two 25 or 50g doses of Covax-19 vaccine had no detectable virus in their lungs or in nasal washes at day 3 post-challenge, suggesting the possibility that Covax-19 vaccine may in addition to protection against lung infection also have the potential to block virus transmission. This data supports advancement of Covax-19 vaccine into human clinical trials.

immunology↗