Immune Response After SARS-CoV-2 (COVID-19) Vaccination in a Context of Non-Hodgkin Lymphoma

The specific immune response to SARS-CoV-2 includes a humoral response - specific IgM appearing 5 days after the onset of symptoms while IgG appears after 14 days - and a T lymphocyte component, with specific activated CD8 and CD4 T lymphocytes. Mortality from infection varies greatly depending on the age of the affected subjects and their comorbidities including a history of cancer. Among these cancers, a history of malignant hemopathy in the 5 years preceding the onset of Covid-19 increases the risk of death by a factor of 3. Among them, lymphoid hemopathies induce hypogammaglobulinemia and / or lymphopenia. These factors combined with chemotherapy and immunotherapy treatments promote the development of infections in affected individuals. Among these, are the anti-CD20 monoclonal antibodies, widely prescribed for treating B-cell non-Hodgkin lymphomas (B-NHL). They induce a deep and lasting B-cell lymphopenia, which can promote infections. They reduce the production of antibodies and the constitution of memory responses to a new pathogen or to a vaccination. In addition, B lymphocytes likely have a key immunomodulatory role in the control of viral infections. A retrospective study in 89 patients with lymphoma and Covid-19 were conducted after the first phase of the epidemic in different centers in the Île-de-France and eastern France regions. With a 6-month follow-up, a pejorative prognostic impact of anti-CD20 monoclonal antibody treatment on Covid-19-related mortality were showed. Vaccination of these at-risk patients is therefore essential. A growing concern is how patients with B-NHL who have been vaccinated with a SARS-CoV-2 mRNA vaccine are protected against infection, depending on whether or not they have received anti-CD20 monoclonal drugs and / or chemotherapy. Knowing the medium-term immunological evolution after vaccination against SARS-CoV-2 in patients with B-cell NHL is necessary in order to be able to adapt the therapeutic and vaccine recommendat