Molecular Classification
Immune Cell, Lymphocyte
Other Names
B Lymphocyte Function, B Cell Activity, Humoral Immunity
Disease Roles
InfectionAutoimmunityImmunodeficiency

B Cell Function Overview

B cells, also known as B lymphocytes, are a critical component of the adaptive immune system. Their primary function is to protect the body from infection by producing antibodies—specialized proteins that recognize and neutralize pathogens such as bacteria and viruses. B cells also play roles in immune regulation, antigen presentation, and maintenance of immune homeostasis. Upon encountering an antigen (a foreign molecule), B cells differentiate into plasma cells that secrete large quantities of antibodies specific to that antigen. Some activated B cells become memory B cells that persist long-term and enable rapid antibody production upon re-exposure to their specific antigen. B cells can internalize antigens via their surface receptors (B cell receptors or BCRs), process them, and present peptide fragments on MHC class II molecules to helper T-cells. Certain subsets of regulatory B-cells produce cytokines like IL-10 that modulate inflammation and help maintain immune balance.

Mechanism of Action

B cell depletion; inhibition of B cell signaling; blockade of B cell survival factors; modulation of B cell activity via cytokines

Biological Functions

Antibody production
Antigen presentation
Cytokine secretion
Immune regulation
Memory formation
Pathogen neutralization

Disease Associations

Infection
Autoimmunity
Immunodeficiency
Cancer
Inflammation

Safety Considerations

  • Increased risk of infection
  • Infusion reactions
  • Hypogammaglobulinemia
  • Progressive multifocal leukoencephalopathy (PML)
  • Cytokine release syndrome

Interacting Drugs

Rituximab
Belimumab
Obinutuzumab
Ofatumumab
Ibrutinib

Associated Biomarkers

Biomarker
B cell count
Antibody levels
Cytokine profiles
Expression of B cell surface markers (e.g., CD19, CD20)
BCR signaling activity