• vaccini
• vaccines
• covid-19
• pazienti
• patients
• sars-cov-2

Coronaviruses are ssRNA+ viruses belonging to the subfamily orthocoronavirinae, genus betacoronavirus.
The first epidemic caused by this family of viruses is dated on 2003, causing the “Severe Acute Respiratory Syndrome” or better known as SARS. Ten years later, a second related agent caused the “Middle East Respiratory Syndrome” (MERS) epidemic.
In the last months of 2019, another coronavirus, SARS-CoV-2, was able to produce the pandemic that is still ongoing, and its related disease, called CoViD-19, Corona VIrus Disease 19.
Usually, SARS-CoV-2 infection is asymptomatic or causes only flu-like clinical manifestations, but in 15% of cases, especially in elderly and/or comorbid patients, it can result in atypical interstitial pneumonia leading to acute respiratory distress syndrome (ARDS). with a lethality rate of 3%.
The sequence homology between SARS-CoV and SARS-CoV-2 is around 80%, which allowed the investigators to focus on highly immunogenic regions previously described especially on the SARS-CoV Spike protein.
Innate and adaptive immunity cooperate in the response to viral infection. Antibody production is critical in the control of infection and monoclonal anti- SARS-CoV-2 antibodies have been developed for therapeutic purposes.
Data obtained after 2003 SARS-CoV epidemic indicate that anti- virus antibodies react with the S1 region 303-625 (containing RDB) and S2 1029-1192. Furthermore, it has been shown that a subset of anti-S1 antibodies can have neutralizing properties, blocking the entry of viral cells. On the basis of these data, vaccines have been developed that aim at inducing an immune response to the Spike protein.

The aim of this thesis was to evaluate anti Spike/RBD reactivity in subjects affected by autoimmune diseases or haematological/oncological disorders and vaccinated with mRNA-based vaccines. Moreover, we focused therapies, such as Bruton kinase inhibitors or checkpoint inhibitors, that influencing the functionality of the immune system on the effect may affect vaccine efficacy.
Sera from medically fragile patients have been collected before first dose, and 20 days after second dose of Pfizer/Moderna vaccines. Sera from blood donors collected pre-pandemia have been used as control group.
Recombinant Spike and RBD were a kind gift of Gianpietro Corradin from the University of Lausanne, while synthetic peptides covering the RBD region have been obtained by conventional F-Moc synthesis, in collaboration with the Laboratory of Peptide & Protein Chemistry and Biology of the University of Florence.

Sera from all the subjects recruited in the project have been tested by ELISA on the recombinant proteins and on the selected panel of peptides. Sensitivity and specificity of each ELISA assay have been calculated.
The neutralizing antibody ability was evaluated using a commercial Spike protein inhibition assay already validated as SARS-CoV-2 surrogate virus neutralization assay.
Results obtained in laboratory have been correlated with patient’s clinical characteristics and therapies.

Preliminary results suggest that patients with autoimmune disorders generally develop a potent immune response after vaccination. In a few cases no anti-Spike/RBD activity was observed even after second dose of mRNA vaccine.
Studies are in progress to characterize in more detail the patient’s immune response.  
Coronaviruses are ssRNA+ viruses belonging to the subfamily orthocoronavirinae, genus betacoronavirus.
The first epidemic caused by this family of viruses is dated on 2003, causing the “Severe Acute Respiratory Syndrome” or better known as SARS. Ten years later, a second related agent caused the “Middle East Respiratory Syndrome” (MERS) epidemic.
In the last months of 2019, another coronavirus, SARS-CoV-2, was able to produce the pandemic that is still ongoing, and its related disease, called CoViD-19, Corona VIrus Disease 19.
Usually, SARS-CoV-2 infection is asymptomatic or causes only flu-like clinical manifestations, but in 15% of cases, especially in elderly and/or comorbid patients, it can result in atypical interstitial pneumonia leading to acute respiratory distress syndrome (ARDS). with a lethality rate of 3%.
The sequence homology between SARS-CoV and SARS-CoV-2 is around 80%, which allowed the investigators to focus on highly immunogenic regions previously described especially on the SARS-CoV Spike protein.
Innate and adaptive immunity cooperate in the response to viral infection. Antibody production is critical in the control of infection and monoclonal anti- SARS-CoV-2 antibodies have been developed for therapeutic purposes.
Data obtained after 2003 SARS-CoV epidemic indicate that anti- virus antibodies react with the S1 region 303-625 (containing RDB) and S2 1029-1192. Furthermore, it has been shown that a subset of anti-S1 antibodies can have neutralizing properties, blocking the entry of viral cells. On the basis of these data, vaccines have been developed that aim at inducing an immune response to the Spike protein.

The aim of this thesis was to evaluate anti Spike/RBD reactivity in subjects affected by autoimmune diseases or haematological/oncological disorders and vaccinated with mRNA-based vaccines. Moreover, we focused therapies, such as Bruton kinase inhibitors or checkpoint inhibitors, that influencing the functionality of the immune system on the effect may affect vaccine efficacy.
Sera from medically fragile patients have been collected before first dose, and 20 days after second dose of Pfizer/Moderna vaccines. Sera from blood donors collected pre-pandemia have been used as control group.
Recombinant Spike and RBD were a kind gift of Gianpietro Corradin from the University of Lausanne, while synthetic peptides covering the RBD region have been obtained by conventional F-Moc synthesis, in collaboration with the Laboratory of Peptide & Protein Chemistry and Biology of the University of Florence.

Sera from all the subjects recruited in the project have been tested by ELISA on the recombinant proteins and on the selected panel of peptides. Sensitivity and specificity of each ELISA assay have been calculated.
The neutralizing antibody ability was evaluated using a commercial Spike protein inhibition assay already validated as SARS-CoV-2 surrogate virus neutralization assay.
Results obtained in laboratory have been correlated with patient’s clinical characteristics and therapies.

Preliminary results suggest that patients with autoimmune disorders generally develop a potent immune response after vaccination. In a few cases no anti-Spike/RBD activity was observed even after second dose of mRNA vaccine.
Studies are in progress to characterize in more detail the patient’s immune response.