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Bayarri-Olmos, R.

Publications and source records attributed to Bayarri-Olmos, R..

4 recordsLinked to original sources

Bioactive Enhanced Adjuvant Chemokine Oligonucleotide Nanoparticles (BEACONs) for Mucosal Vaccination Against Genital Herpes

Genital herpes, caused by herpes simplex virus-2 (HSV-2), remains a prevalent sexually transmitted infection with no available vaccine. Effective local immunity--including tissue-resident memory T cells (TRMs) and luminal antibodies--provides immediate viral control. Here, we developed Bioactive Enhanced Adjuvant Chemokine Oligonucleotide Nanoparticles (BEACON) formed via electrostatic interactions between CpG oligodeoxynucleotides (CpG ODN) and the chemokine CXCL9. This adjuvant enhances antigen-presenting cell engagement and innate immune signaling, promotes CD8+ T cell recruitment, and reduces local neutrophilic inflammation relative to CpG ODN. Co-administered vaginally with HSV-2 glycoproteins following intramuscular priming, BEACON improved protection against HSV-2 by increasing local CD8+ TRM populations and mucosal IgG and IgA responses. Vaccine-mediated protection required local delivery of both antigen and adjuvant, and was significantly reduced by CD8+ T cell or B cell depletion. These findings highlight the potential of engineered mucosal adjuvants for vaccines targeting genital herpes and other sexually transmitted infections. One-sentence summaryWe developed BEACON, a mucosal adjuvant that elicits protective immunity against genital herpes simplex virus 2 infection in mice.

immunology↗

C1q/MASP complexes - hybrid complexes of classical and lectin pathway proteins are found in the circulation

Complement pathways, traditionally regarded as separate entities in vitro, are increasingly noted for cross-communication and bypass mechanisms. Among these, the MBL/Ficolin/CL associated serine protease-3 (MASP-3) -- a component of lectin pathway pattern recognition receptors (PRMs) -- has shown the ability to process critical substrates like pro-factor D and insulin growth factor binding protein-5 (IGFBP-5). Given shared features between lectin pathway PRMs and C1q from the classical pathway, we hypothesized that C1q might be a viable in vivo binding partner for the MASPs. We used microscale thermophoresis, ELISA and immunoprecipitation assays to detect C1q/MASP complexes and functionally assessed the complexes through enzymatic cleavage assays. C1q/MASP-3 complexes were detected in human serum and correlated well with MASP-3 serum levels in healthy individuals. The binding affinity between MASP-3 and C1q in vitro was in the nanomolar range, and the interaction was calcium-dependent, as demonstrated by their dissociation in the presence of EDTA. Furthermore, most of the circulating C1q-bound MASP-3 was activated. Based on immunoprecipitatin, also C1q/MASP-2 complexes appereared to be present in serum. Finally, C1q/MASP-2 and C1q/MASP-3 in vitro complexes were able to cleave C4 and pro-factor D, respectively. Our study reveals the existence of C1q/MASP complexes in the circulation of healthy individuals and both C1q/MASP-2 and C1q/MASP-3 complexes display proteolytic activity. Hence, this study uncovers a crosstalk route between complement pathways not previously described.

immunology↗

The SARS-CoV-2 Y453F mink variant displays a striking increase in ACE-2 affinity but does not challenge antibody neutralization

SARS-CoV-2 transmission from humans to animals has been reported for many domesticated species, including cats, dogs and minks. Identification of novel spike gene mutations appearing in minks has raised major concerns about potential immune evasion and challenges for the global vaccine strategy. The genetic variant, known as "cluster-five", arose among farmed minks in Denmark and resulted in a complete shutdown of the worlds largest mink production. However, the functional properties of this new variant are not established. Here we present functional data on the Y453F cluster-five receptor-binding domain (RBD) and show that it does not decrease established humoral immunity or affect the neutralizing response in a vaccine model based on wild-type RBD or spike. However, it binds the human ACE-2 receptor with a four-fold higher affinity suggesting an enhanced transmission capacity and a possible challenge for viral control.

immunology↗

Proteomics-based comparative mapping of the human brown and white adipocyte secretome reveals EPDR1 as a novel batokine

Secreted proteins from adipose tissue play a role in metabolic cross-talk and homeostasis. We performed high sensitivity mass spectrometry-based proteomics on the cell media of in vitro differentiated, non-immortalized brown adipocytes derived from supraclavicular adipose of adult humans and white adipocytes derived from subcutaneous adipose of adult humans. We identified 471 potentially secreted proteins covering interesting protein categories such as hormones, growth factors, growth factor binding proteins, cytokines, extracellular matrix proteins, and proteins of the complement system, which were differentially regulated in brown and white adipocytes. A total of 101 proteins were exclusively quantified in brown adipocytes, among these ependymin-related protein 1 (EPDR1). Ablation of EPDR1 impaired the induction of thermogenic transcripts in response to norepinephrine in brown adipocytes, while EPDR1-treated mice increased their energy consumption, suggesting a role in brown fat commitment and activation. Our work reveals substantial differences between the secretomes of brown and white human adipocytes and identifies novel candidate batokines.

physiology↗