SARS-CoV-2 Viral Load and Cytokine Dynamics Profile as Early Signatures of Long COVID Condition in Hospitalized Individuals.

Background: The global pandemic caused by SARS-CoV-2 has resulted in millions of people experiencing long COVID condition, a range of persistent symptoms following the acute phase, with an estimated prevalence of 27%-64%.

Materials And Methods: To understand its pathophysiology, we conducted a longitudinal study on viral load and cytokine dynamics in individuals with confirmed SARS-CoV-2 infection. We used reverse transcriptase droplet digital PCR to quantify viral RNA from nasopharyngeal swabs and employed multiplex technology to measure plasma cytokine levels in a cohort of people with SARS-CoV-2 infection.

Polymeric nanostructure vaccines: applications and challenges.

Introduction: The use of biocompatible polymers, from natural or synthetic sources, opened the door for a new era in vaccine research. These polymers offer the possibility to develop nanostructured antigen carriers that can be easily internalized by antigen-presenting cells, due to their nanometric size. Besides, the incorporation of an adjuvant allows increasing and modulating the immune response for both, polymers with or without self-adjuvant properties.

Multi-parameter flow cytometry immunophenotyping distinguishes different stages of tuberculosis infection.

Objectives: To identify new potential host biomarkers in blood to discriminate between active TB patients, uninfected (NoTBI) and latently infected contacts (LTBI).

Methods: A blood cell count was performed to study parent leukocyte populations. Peripheral blood mononuclear cells (PBMCs) were isolated and a multi-parameter flow cytometry assay was conducted to study the distribution of basal and Mycobacterium tuberculosis (Mtb)-stimulated lymphocytes.

The size and composition of polymeric nanocapsules dictate their interaction with macrophages and biodistribution in zebrafish.

Macrophages are pivotal cells of the innate immune system specialized in the phagocytosis of foreign elements. Nanoparticles intentionally designed to target macrophages and modulate their response are of especial interest in the case of chronic inflammatory diseases, cancer and for vaccine development. This work aimed to understand the role of size and shell composition of polymeric nanocapsules (NCs) in their interaction with macrophages, both in vitro and in vivo.

Protamine Nanocapsules for the Development of Thermostable Adjuvanted Nanovaccines.

One of the main challenges in the development of vaccine has been to improve their stability at room temperature and eliminate the limitations associated with the cold chain storage. In this paper, we describe the development and optimization of thermostable nanocarriers consisting of an oily core with immunostimulating activity, containing squalene or α tocopherol surrounded by a protamine shell. The results showed that these nanocapsules can efficiently associate the recombinant hepatitis B surface antigen (rHBsAg) without compromising its antigenicity.

Polymeric Nanocapsules for Vaccine Delivery: Influence of the Polymeric Shell on the Interaction With the Immune System.

The use of biomaterials and nanosystems in antigen delivery has played a major role in the development of novel vaccine formulations in the last few decades. In an effort to gain a deeper understanding of the interactions between these systems and immunocompetent cells, we describe here a systematic and study on three types of polymeric nanocapsules (NCs). These carriers, which contained protamine (PR), polyarginine (PARG), or chitosan (CS) in the external shell, and their corresponding nanoemulsion were prepared, and their main physicochemical properties were characterized.

Highly versatile immunostimulating nanocapsules for specific immune potentiation.

Aim: To develop a new core-shell type (nanocapsules) adjuvant system composed of squalene and polyglucosamine (PG) and to evaluate its immunostimulant capacity.

Results: The defined PG nanocapsules exhibited the capacity to efficiently associate the selected antigens (recombinant hepatitis B surface antigen and hemagglutinin of influenza virus) onto their polymeric surface (70-75%), and the immunostimulant imiquimod within the oily core. The resulting nanovaccines, with a particle size of 200-250 nm and a positive zeta-potential (∼+60 mV), were able to significantly potentiate and modulate the immune response to the selected antigens upon intramuscular administration to mice.

Co-delivery of viral proteins and a TLR7 agonist from polysaccharide nanocapsules: a needle-free vaccination strategy.

Here we report a new nanotechnology-based nasal vaccination concept intended to elicit both, specific humoral and cellular immune responses. The concept relies on the use of a multifunctional antigen nanocarrier consisting of a hydrophobic nanocore, which can allocate lipophilic immunostimulants, and a polymeric corona made of chitosan (CS), intended to associate antigens and facilitate their transport across the nasal mucosa. The Toll-like receptor 7 (TLR7) agonist, imiquimod, and the recombinant hepatitis B surface antigen (HB), were selected as model molecules for the validation of the concept.

A polymer/oil based nanovaccine as a single-dose immunization approach.

The recognized necessity for new antigen delivery carriers with the capacity to boost, modulate and prolong neutralizing immune responses prompted our approach, in which we describe a multifunctional nanocarrier consisting of an oily nanocontainer protected by a polymeric shell made of chitosan (CS), named CS nanocapsules (CSNC). The CS shell can associate the antigen on its surface, whereas the oily core might provide additional immunostimulating properties. In this first characterization of the system, we intended to study the influence of different antigen organizations on the nanocarrier's surface (using the recombinant hepatitis B surface antigen -rHBsAg- as a model antigen) on their long-term immunopotentiating effect, without any additional immunostimulant.