B lymphocytes in COVID-19: a tale of harmony and discordance

Abstract

B lymphocytes play a vital role in the human defense against viral infections by producing specific antibodies. They are also critical for the prevention of infectious diseases by vaccination, and their activation influences the efficacy of the vaccination. Since the beginning of coronavirus disease 2019 (COVID-19), which became the main concern of the world health system, many efforts have been made to treat and prevent the disease. However, for the development of successful therapeutics and vaccines, it is necessary to understand the interplay between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, and the immune system. The innate immune system provides primary and nonspecific defense against the virus, but within several days after infection, a virus-specific immune response is provided first by antibody-producing B cells, which are converted after the resolution of disease to memory B cells, which provide long-term immunity. Although a failure in B cell activation or B cell dysfunction can cause a severe form of the disease and also lead to vaccination inefficiency, some individuals with B cell immunodeficiency have shown less production of the cytokine IL-6, resulting in a better disease outcome. In this review, we present the latest findings on the interaction between SARS-CoV-2 and B lymphocytes during COVID-19 infection.

Immune Response after Anti-SARS-CoV-2 mRNA Vaccination in Relation to Cellular Immunity, Vitamin D and Comorbidities in Hemodialysis Patients

“…B lymphocytes play a pivotal role in the human defense against viral infections by generating targeted antibodies. Additionally, they are crucial for preventing infectious diseases through vaccination [27]. Therefore, it is no coincidence that a positive correlation between B lymphocytes (CD19+) and anti-SARS-CoV-2 antibodies IgG titers in the maintenance dialysis patients group was obtained.…”

COVID-19 infection characteristics, risk factors and its potential impacts on Takayasu arteritis: a web-based survey in a large cohort

“…In line with this, we found that the percentage of CD19 + B cells was lowest in patients on GCs and csDMARDs. As B cells play a fundamental role in the prevention of COVID-19 ( 35 ), whether the low proportion of B cells is associated with a high rate of infection in these patients requires further validation.…”

Genes, inflammatory response, tolerance, and resistance to virus infections in migratory birds, bats, and rodents

“…The humoral immune response by B-lymphocytes is part of the adaptive immune mechanisms, controlling viral infections through the neutralizing antibodies and antibody-dependent cellular toxicity ( 212 , 213 ). The elimination of viral infection and the apoptosis of virally infected cells is also provided by B lymphocytes through effector molecules, exhibiting antibody-independent functions ( 214 ).…”

“…The elimination of viral infection and the apoptosis of virally infected cells is also provided by B lymphocytes through effector molecules, exhibiting antibody-independent functions ( 214 ). However, lack of B cells has been associated with a mild form of COVID-19 suggesting that inflammatory cytokines, especially IL-6, may have a central role in the disease severity ( 213 ). In fact, patients with agammaglobulinemia (caused by a lack of B lymphocytes), show mild symptoms, short duration, and no need of treatment by IL-6 inhibitors, while patients exhibiting variable immune deficiencies with dysfunctional B lymphocytes, (also showing significant low levels of immunoglobulins in the serum), show severe outcomes and require mechanical ventilation, antiretroviral agents and IL-6-blocking agents ( 215 ).…”