Pan-neutralizing, germline-encoded antibodies against SARS-CoV-2: Addressing the long-term problem of escape variants.

Despite the initially reported high efficacy of vaccines directed against ancestral SARS-CoV-2, repeated infections in both unvaccinated and vaccinated populations remain a major global health challenge. Because of mutation-mediated immune escape by variants-of-concern (VOC), approved neutralizing antibodies (neutAbs) effective against the original strains have been rendered non-protective. Identification and characterization of mutation-independent pan-neutralizing antibody responses are therefore essential for controlling the pandemic.

Longitudinal waning of mRNA vaccine-induced neutralizing antibodies against SARS-CoV-2 detected by an LFIA rapid test.

Although mRNA vaccines against SARS-CoV-2 were highly efficacious against severe illness and hospitalization, they seem to be less effective in preventing infection months after vaccination, especially with the Delta variant. Breakthrough infections might be due to higher infectivity of the variants, relaxed protective measures by the general public in "COVID-19 fatigue", and/or waning immunity post-vaccination. Determining the neutralizing antibody levels in a longitudinal manner may address this issue, but technical complexity of classic assays precludes easy detection and quick answers.

Structural and functional characterization of engineered bifunctional fusion proteins of CD39 and CD73 ectonucleotidases.

Extracellular diphosphate and triphosphate nucleotides are released from activated or injured cells to trigger vascular and immune P purinergic receptors, provoking inflammation and vascular thrombosis. These metabokines are scavenged by ectonucleoside triphosphate diphosphohydrolase-1 (E-NTPDase1 or CD39). Further degradation of the monophosphate nucleoside end products occurs by surface ecto-5'-nucleotidase (NMPase) or CD73.

Galactosylation of the Secondary Cell Wall Polysaccharide of Bacillus anthracis and Its Contribution to Anthrax Pathogenesis.

, the causative agent of anthrax disease, elaborates a secondary cell wall polysaccharide (SCWP) that is essential for bacterial growth and cell division. SCWP is comprised of trisaccharide repeats with the structure, [→4)-β-ManNAc-(1→4)-β-GlcNAc(3-α-Gal)-(1→6)-α-GlcNAc(3-α-Gal, 4-β-Gal)-(1→] The genes whose products promote the galactosylation of SCWP are not yet known. We show here that the expression of , encoding a UDP-glucose 4-epimerase necessary for the synthesis of UDP-galactose, is required for SCWP galactosylation.

LytR-CpsA-Psr enzymes as determinants of Bacillus anthracis secondary cell wall polysaccharide assembly.

Bacillus anthracis, the causative agent of anthrax, replicates as chains of vegetative cells by regulating the separation of septal peptidoglycan. Surface (S)-layer proteins and associated proteins (BSLs) function as chain length determinants and bind to the secondary cell wall polysaccharide (SCWP). In this study, we identified the B.