Describes b-cell, receptors and it's function in defense system

1. SEMINAR PRESENTATION
ON
B CELL RECEPTOR TARGETING IN DESEASES AND
VACCINE
BY
ADERIYE PRECIOUS OLUWADAMILOLA
MATRIC NUMBER: 178858057
Course code: BCH404
BIOCHEMISTRY DEPARTMENT
FACULTY OF SCIENCE
EKITI STATE UNIVERSITY

2. OUTLINES
 INTRODUCTION TO B CELLS
 DEVELOPMENT OF B CELLS
 ROLES OF B CELLS IN HEALTH AND DISEASES
 B CELL RESPONSE TO VACCINATION
 CONCLUSION
 RECOMMENDATION

3. INTRODUCTION TO B CELLS
 The immune system is composed of numerous cells that are required
to generate innate and adaptive immune responses.
 B cells are lymphocytes that recognize antigens through a molecule
called the B cell receptor (BCR).
 The BCR is a surface immunoglobulin (Ig) molecule that recognizes
the antigen and is associated with two additional proteins, which
transduce the signal.
 The B cell receptor (BCR) is a transmembrane protein on the surface
of a B cell. A B cell receptor is composed of a membrane-bound
immunoglobulin molecule and a signal transduction moiety

5. B CELLS IN HEALTH AND DISEASE
 B cells play a key role in regulating the immune system by producing
antibodies, acting as antigen-presenting cells, providing support to
other mononuclear cells, and contributing directly to inflammatory
pathways
 The use of monoclonal antibody treatment to target and selectively
deplete B cells is well established in the treatment of B-cell
malignancies and a similar approach is now being investigated in the
treatment of autoimmune disorders
 In addition to producing antibodies, B cells can act as efficient APCs
to stimulate T cells, and to allow optimal development of memory in
the CD4+ T-cell population

7. B CELL RESPONSE TO VACCINATION
 As one of the most important weapons against infectious diseases,
vaccines have saved countless lives since their first use in the late
eighteenth century.
 Antibodies produced by effector B cells upon vaccination play a
critical role in mediating protection
EXTRAFOLLICULAR RESPONSE AND GERMINAL CENTER RESPONSE
 In response to pathogen infection or vaccination, B cells can either differentiate into short-lived
plasmablasts (SLPBs) through the extrafollicular (EF) response or form germinal centers (GCs).
 The EF response can be T cell dependent or T cell independent
 The EF response generates SLPBs that give rise to the first wave of antibodies
 GC B cells express activation-induced cytidine deaminase (AID) to facilitate BCR mutation,
altering BCR affinity for the antigen

8. In response to vaccination with an antigen (e.g. spike protein from SARS-CoV2), antigen-specific B cells
may go through different pathways to mount an effective humoral immune response. Some B cells can
quickly differentiate into plasmablasts (PBs) and early memory B cells (MBCs) through the extra follicular
(EF) response.

9. CONCLUSION AND RECOMMENDATION
 B cells are essential for efficient immune responses and the
maintenance of health. However, accumulating evidence points to
the involvement of B cells in the pathophysiology of several
autoimmune disorders, suggesting their potential as a relevant
target for therapeutic intervention
 Additional studies are warranted to further characterize the role of
B cells in autoimmune diseases and the therapeutic utility of B-cell
depletion or other modalities that target B cells, such as those that
alter B-cell activation.

10. THANKS
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