Randomised trial of same vs opposite arm co-administration of inactivated influenza and SARS-CoV-2 mRNA vaccines.

Background: The immunogenicity of current influenza vaccines need improvement. Inactivated influenza and COVID-19 mRNA vaccines can be co-administered but randomized controlled trial data is lacking on whether the two vaccines are more immunogenic if given in the same or opposite arms. Murine studies suggest mRNA vaccines can adjuvant influenza vaccines when co-formulated and delivered together.

Blood Distribution of SARS-CoV-2 Lipid Nanoparticle mRNA Vaccine in Humans.

Lipid nanoparticle mRNA vaccines are an exciting but emerging technology used in humans. There is limited understanding of the factors that influence their biodistribution and immunogenicity. Antibodies to poly(ethylene glycol) (PEG), which is on the surface of the lipid nanoparticle, are detectable in humans and boosted by human mRNA vaccination.

Mucosal antibody responses following Vaxzevria vaccination.

Mucosal antibodies play a key role in protection against breakthrough COVID-19 infections and emerging viral variants. Intramuscular adenovirus-based vaccination (Vaxzevria) only weakly induces nasal IgG and IgA responses, unless vaccinees have been previously infected. However, little is known about how Vaxzevria vaccination impacts the ability of mucosal antibodies to induce Fc responses, particularly against SARS-CoV-2 variants of concern (VoCs).

Durable reprogramming of neutralizing antibody responses following Omicron breakthrough infection.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) breakthrough infection of vaccinated individuals is increasingly common with the circulation of highly immune evasive and transmissible Omicron variants. Here, we report the dynamics and durability of recalled spike-specific humoral immunity following Omicron BA.1 or BA.

SARS-CoV-2 breakthrough infection induces rapid memory and de novo T cell responses.

Although the protective role of neutralizing antibodies against COVID-19 is well established, questions remain about the relative importance of cellular immunity. Using 6 pMHC multimers in a cohort with early and frequent sampling, we define the phenotype and kinetics of recalled and primary T cell responses following Delta or Omicron breakthrough infection in previously vaccinated individuals. Recall of spike-specific CD4 T cells was rapid, with cellular proliferation and extensive activation evident as early as 1 day post symptom onset.

The magnitude and timing of recalled immunity after breakthrough infection is shaped by SARS-CoV-2 variants.

Vaccination against SARS-CoV-2 protects from infection and improves clinical outcomes in breakthrough infections, likely reflecting residual vaccine-elicited immunity and recall of immunological memory. Here, we define the early kinetics of spike-specific humoral and cellular immunity after vaccination of seropositive individuals and after Delta or Omicron breakthrough infection in vaccinated individuals. Early longitudinal sampling revealed the timing and magnitude of recall, with the phenotypic activation of B cells preceding an increase in neutralizing antibody titers.

Establishment and recall of SARS-CoV-2 spike epitope-specific CD4 T cell memory.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and vaccination elicit CD4 T cell responses to the spike protein, including circulating follicular helper T (cT) cells that correlate with neutralizing antibodies. Using a novel HLA-DRB1*15:01/S tetramer to track spike-specific CD4 T cells, we show that primary infection or vaccination induces robust S-specific CXCR5 and cT cell memory responses. Secondary exposure induced recall of CD4 T cells with a transitory CXCR3 phenotype, and drove expansion of cT cells transiently expressing ICOS, CD38 and PD-1.

Tear antibodies to SARS-CoV-2: implications for transmission.

Objectives: SARS-CoV-2 can be transmitted by aerosols, and the ocular surface may be an important route of transmission. Little is known about protective antibody responses to SARS-CoV-2 in tears after infection or vaccination. We analysed the SARS-CoV-2-specific IgG and IgA responses in human tears after either COVID-19 infection or vaccination.

Intra-Anal Imiquimod Cream against Human Papillomavirus Infection in Men Who Have Sex with Men Living with HIV: A Single-Arm, Open-Label Pilot Study.

Men who have sex with men (MSM) living with HIV have a high prevalence and incidence of anal high-risk human papillomavirus (hrHPV) and anal cancer. We conducted an open-label, single-arm pilot study to examine the tolerability of imiquimod cream among MSM aged ≥18 years, living with HIV, who tested positive for anal hrHPV at Melbourne Sexual Health Centre between April 2018 and June 2020. We instructed men to apply 6.

Evolution of immune responses to SARS-CoV-2 in mild-moderate COVID-19.

The durability of infection-induced SARS-CoV-2 immunity has major implications for reinfection and vaccine development. Here, we show a comprehensive profile of antibody, B cell and T cell dynamics over time in a cohort of patients who have recovered from mild-moderate COVID-19. Binding and neutralising antibody responses, together with individual serum clonotypes, decay over the first 4 months post-infection.

Humoral and circulating follicular helper T cell responses in recovered patients with COVID-19.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has dramatically expedited global vaccine development efforts, most targeting the viral 'spike' glycoprotein (S). S localizes on the virion surface and mediates recognition of cellular receptor angiotensin-converting enzyme 2 (ACE2). Eliciting neutralizing antibodies that block S-ACE2 interaction, or indirectly prevent membrane fusion, constitute an attractive modality for vaccine-elicited protection.

Meibomian gland dropout is associated with immunodeficiency at HIV diagnosis: Implications for dry eye disease.

Aim: To characterize anterior eye health and tear film characteristics in individuals with human immunodeficiency virus (HIV) undergoing anti-retroviral therapy.

Methods: This cross-sectional study involved 35 adults, categorized as healthy controls (n = 18) or as HIV-positive patients (n = 17), with no history of opportunistic infection or current ocular fundus abnormalities. Participants underwent a comprehensive anterior eye assessment.

Hsc70-induced changes in clathrin-auxilin cage structure suggest a role for clathrin light chains in cage disassembly.

The molecular chaperone, Hsc70, together with its co-factor, auxilin, facilitates the ATP-dependent removal of clathrin during clathrin-mediated endocytosis in cells. We have used cryo-electron microscopy to determine the 3D structure of a complex of clathrin, auxilin(401-910) and Hsc70 at pH 6 in the presence of ATP, frozen within 20 seconds of adding Hsc70 in order to visualize events that follow the binding of Hsc70 to clathrin and auxilin before clathrin disassembly. In this map, we observe density beneath the vertex of the cage that we attribute to bound Hsc70.

Architecture of the Pol III-clamp-exonuclease complex reveals key roles of the exonuclease subunit in processive DNA synthesis and repair.

DNA polymerase III (Pol III) is the catalytic α subunit of the bacterial DNA Polymerase III holoenzyme. To reach maximum activity, Pol III binds to the DNA sliding clamp β and the exonuclease ε that provide processivity and proofreading, respectively. Here, we characterize the architecture of the Pol III-clamp-exonuclease complex by chemical crosslinking combined with mass spectrometry and biochemical methods, providing the first structural view of the trimeric complex.

Molecular basis for recognition of dilysine trafficking motifs by COPI.

COPI mediates retrograde trafficking from the Golgi to the endoplasmic reticulum (ER) and within the Golgi stack, sorting transmembrane proteins bearing C-terminal KKxx or KxKxx motifs. The structure of KxKxx motifs bound to the N-terminal WD-repeat domain of β'-COP identifies electrostatic contacts between the motif and complementary patches at the center of the β'-COP propeller. An absolute requirement of a two-residue spacing between the terminal carboxylate group and first lysine residue results from interactions of carbonyl groups in the motif backbone with basic side chains of β'-COP.

Structural basis of the intracellular sorting of the SNARE VAMP7 by the AP3 adaptor complex.

VAMP7 is involved in the fusion of late endocytic compartments with other membranes. One possible mechanism of VAMP7 delivery to these late compartments is via the AP3 trafficking adaptor. We show that the linker of the δ-adaptin subunit of AP3 binds the VAMP7 longin domain and determines the structure of their complex.

Role of the nurse immuniser in implementing and maintaining the National Human Papillomavirus 'Cervical Cancer' Vaccine rollout through a school-based program in Victoria.

In an effort to understand the strengths and limitations of current approaches to human papillomavirus vaccine (HPV) delivery in schools, we conducted an audit of nurse immunisers (NI). In this survey of 159 Victorian NI, the NI perceived that knowledge, safety and side effects were among the most important issues raised by parents, schoolgirls, and teachers in the school setting. The most common concern identified by NIs was the physical layout of the vaccination setting (41%), followed by safety, then knowledge of the vaccine.

Prevalence of HSV-2 antibody in a Melbourne antenatal population attending a tertiary obstetric hospital.

Objective: To determine the herpes simplex virus 2 (HSV-2) seroprevalence rate in a Melbourne antenatal cohort.

Design: Prospective collection of serum and questionnaires in 1371 women attending an outpatient antenatal clinic.

Setting: A tertiary obstetric hospital in metropolitan Melbourne.

Structure and analysis of FCHo2 F-BAR domain: a dimerizing and membrane recruitment module that effects membrane curvature.

A spectrum of membrane curvatures exists within cells, and proteins have evolved different modules to detect, create, and maintain these curvatures. Here we present the crystal structure of one such module found within human FCHo2. This F-BAR (extended FCH) module consists of two F-BAR domains, forming an intrinsically curved all-helical antiparallel dimer with a Kd of 2.

Mechanism of endophilin N-BAR domain-mediated membrane curvature.

Endophilin-A1 is a BAR domain-containing protein enriched at synapses and is implicated in synaptic vesicle endocytosis. It binds to dynamin and synaptojanin via a C-terminal SH3 domain. We examine the mechanism by which the BAR domain and an N-terminal amphipathic helix, which folds upon membrane binding, work as a functional unit (the N-BAR domain) to promote dimerisation and membrane curvature generation.

Structural analysis of the interaction between the SNARE Tlg1 and Vps51.

Membrane fusion in cells involves the interaction of SNARE proteins on apposing membranes. Formation of SNARE complexes is preceded by tethering events, and a number of protein complexes that are thought to mediate this have been identified. The VFT or GARP complex is required for endosome-Golgi traffic in yeast.

Location of auxilin within a clathrin cage.

The Dna J homologue, auxilin, acts as a co-chaperone for Hsc70 in the uncoating of clathrin-coated vesicles during endocytosis. Biochemical studies have aided understanding of the uncoating mechanism but until now there was no structural information on how auxilin interacts with the clathrin cage. Here we have determined the three-dimensional structure of a complex of auxilin with clathrin cages by cryo-electron microscopy and single particle analysis.