Immune response B cells

Homo sapiens (compared to Drosophila melanogaster) Large-scale gene duplications with substantial expansion of genes involved in acquired immune response (B cells, T cells, major histocompatibility complex genes, cytokines, chemokines and their receptors), plasma proteases (complement and hemostatic proteins), proteins associated with apoptotic regulation and proteins related to neuronal network formation and electrical coupling... 

To circumvent these two problems and taking advantage of the VLP stability, some methods have been developed to introduce multiple epitopes in the same VLP. One example is the use of porcine parvovirus VLP containing epitopes to induce cellular immune response (B cells, CD4+, and CTL). This strategy should allow the production of cheaper and more potent vaccines that will in turn induce a more effective immune response... 

B and T cells are involved in the control as well as effectors of the immune response. B cells can differentiate into mature plasmocytes that produce antibodies, and are therefore implicated in the humoral immune response. T lymphocytes are the major actors of the cellular immune response (Akashi et al, 1999 Hardy and Hayakawa, 2001). 

After activation, cytotoxic T cells emerge from lymphoid organs to infiltrate the graft and trigger the immune response. These cells have been shown to induce graft destruction via two mechanisms (1) secretion of the cytotoxic proteins perforin and granzyme B, and (2) induction of cellular apoptosis... 

To initiate a T-cell immune response, antigen presenting cells have to display antigenic peptides com-plexed with the major histocompatibility complex (MHC) on their cell surface. The T-cell receptor of CDS cells is specific for the peptide-MHC class I complex while the CD4 cell receptor binds the peptide-MHC class II complex. This binding of the peptide-MHC II complex stimulates CD4 cell proliferation and subsequent lymphokine release. This CD4 cell response can initiate a delayed hypersensitivity reaction. However CD4 activation and the production of various lymphokines is also needed for the generation of cytotoxic T-cells and for the differentiation of plasma cells from B-lymphocytes and the antibody response by these plasma cells. For their role in also the humoral immune response CD4 cells are called T-helper cells. 

Overview of the Immune System The Humoral Response B Cells and T Cells Working Together... 

The efficacy of polysaccharide vaccine in preventing invasive pnenmococcal disease, pnenmonia, and death has been assessed in a donble-blind, randomized, placebo-controlled trial in 1392 HIVl-infected adnlts in Uganda (14). The vaccine was well tolerated. However, it was ineffective and is not recommended for nse in HIVl-infected indivi-dnals. Reassessment of recommendations for polysaccharide vaccine immunization may be necessary in some countries. The authors suggested that the vaccine causes destruction of polysaccharide-responsive B cell clones. 

HBV is not directly cytopathic instead liver injury is immune related, and T lymphocytes are important for both the host cellular and humoral responses. Recovery from acute HBV infection depends on both B-cell and T-ceU responses. B-cell-dependent antibodies are produced to presurface and surface antigens. Cytotoxic T lymphocyte response is mounted against multiple epitopes in the HBV envelope, nucleocapsid, and polymerase regions. Cytotoxic T lymphocyte-mediated lysis of infected hepatic cells occurs, resulting in liver injury. Immune clearance of virus is often accompanied by worsening liver disease, known as a flare. An extreme example of this is seen in fulminant hepatitis B, when there is often no evidence... 

R2. Rabinowitz, J. L., Tsiagbe, V. K., Nicknam, M. H., and Thorbecke, G. J. Germinal center cells are a major IL-5-responsive B cell population in peripheral lymph nodes engaged in the immune response. J. Immunol 145, 2440-2447 (1990). 

Humoral immune response - Lymphatic cells called B lymphocytes synthesize specific immunoglobulin molecules that are excreted from the cell and bind to the invading substance. Binding either precipitates the foreign substance or marks it for destruction by cells called macrophages. 

Binds to Fas receptor induces apoptosis of Fas-containing cells kills T cells activates B cells leading to downregulation of immune response Promotes cell proliferation and differentiation... 

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