B-Cell Response

A second population of Th-cells, Th-2, regulates B-cell responses (see below) by secreting a different set of cytokines including IL-4, IL-5, IL-6, IL-10, or IL-13. 

Iglesias, A., Bauer, J., Litzenburger, T. etal. T- and B-cell responses to myelin oligodendrocyte glycoprotein in experimental autoimmune encephalomyelitis and multiple sclerosis. Glia 36 220-234,2001. 

Mature B lymphocytes express AhR and ARNT,10,12 and the ability of TCDD to suppress primary antibody responses has been known for a long time (reviewed in4). While the precise mechanisms resulting in suppression of T-dependent B cell responses in vivo have not been fully elucidated, it is clear that direct effects of TCDD on B cells plays a role. Studies using two B cell lines with differential AhR expression have linked suppression of LPS-induced IgM production to AhR activation, and have shown that AhR interactions within the 3 alpha immunoglobulin heavy chain enhancer directly influence antibody production.52-54 TCDD also appears to directly modulate the expression of CD19 on human B cells, suggesting another mechanism by which TCDD down-modulates the responsiveness of mature B cells.55... 

Pregnant mice exposed to benzene from gestation day 12.5 to 19.5 resulted in the reduction of fetal liver pre-B and B cells. Responsiveness to the B cell mitogen LPS was decreased in spleen cell cultures. The results indicate that in utero exposure to benzene alters fetal lymphopoiesis that may be responsible for compromised immune responsiveness postnatally.104... 

Lim HW, Hillsamer P, Kim CH Regulatory T cells can migrate to follicles upon T cell activation and suppress GC-Th cells and GC-Th cell-driven B cell responses. J Clin Invest 2004 114 1640-1649. 

The synovial arrays were incubated with the sera from patients with early and severe RA as well as healthy patients. Hierarchical clustering analysis revealed that autoreactive B-cell responses for citrullinated epitopes were present in a subset of patients with early RA, features which are predictive of the development of severe RA. In contrast, autoantibodies directed against native epitopes including several human cartilage gp39 peptides and type II collagen, were associated with features predictive of less severe RA. 

Vajdy, M. (2006). Generation and maintenance of mucosal memory B cell responses Curr. Med. Chem. 13(25) 3023-3037. 

Immunity means being resistant to attack by nonself. The property of immunity to infection or toxicity can occur naturally or be induced in an organism. Immunity can also be active, that is, involve the T and B cell responses, or it can be passive, that is, antibodies can be infused into the infected organism and so curtail the infection process. 

Williams, D.L., Asahi, H., Botkin, D.J. and Stadecker, M.J. (2001) Schistosome infection stimulates host CD4(+)T helper cell and B-cell responses againsta novel egg antigen, thioredoxin peroxidase. Infection and Immunity 69, 1 1 34-11 41. 

Legros, Y., Lafon, C., and Soussi, T. 1994a. Linear antigenic sites defined by the B-cell response to human p53 are localized predominantly in the amino and carboxytermini of protein. Oncogene 9 2071-2076. 

Wiedermann U, Jahn-Schmid B, Bohle B, Repa A, Renz H, Kraft D, Ebner C Suppression of antigen-specific T and B cell responses by intranasal or oral administration of recombinant Bet v 1, the major birch pollen allergen, in a murine model of type I allergy. J Allergy Clin Immunol 1999 103 1202-1210. 

If an injection of Rh0(D) antibody is administered to the mother within 24-72 hours after the birth of an Rh-positive baby, the mother s own antibody response to the foreign Rh0(D)-positive cells is suppressed because the baby s red cells are cleared from circulation before the mother can generate a B cell response against Rh0(D). Therefore, she has no memory B cells that can activate upon subsequent pregnancies with an Rh0(D)-positive fetus. 

Li, X.M., Serebrisky, D., Lee, S.J. et al. 2000. A murine model of peanut anaphylaxis T- and B-cell responses to a major peanut allergen mimic human responses. J Allergy Clin Immunol 106 150-158. 

Bachmann MF, Rohrer UH, KundigTM, Burki K, Hengartner H, Zinkernagel RM. The influence of antigen organization on B cell responsiveness. Science 1993 262 1448-51. 

Memory is built into the immune system such that specific immune T- and B-cell responses to most antigens are activated more rapidly in cases where the immune system has encountered the antigen previously. Memory is mediated by long-lived T and B cells. It is this rapid recall that is responsible for the success of vaccination in preventing subsequent infection. T-independent antigens are an exception in that they give rise to predominantly IgM responses and relatively poor, if any, memory is generated by repeated exposure. 

Phase II of the project example contains an objective describing the desired type and specificity of the B-cell response ( II/2) and it is specific enough in its definition (neutralization of the twofold challenge dose) to serve as a meaningful milestone - provided that the project team agrees on its usefulness at that place. 

Although the exact cause of MS remains unknown, the most significant theories involve an immime process as the mechanism that initiates demyelination. The loss of myelin is variously believed to be due to either a cellular (macrophage andT cell) response or a humoral (antibody and B cell) response. 

These follicular T cells strongly express the CD28-related molecule ICOS (inducible T-cell co-stimulator also known as CD278) and secrete moderate amounts of IL-10, CD278, and IL-10 act as co-sdmulatory factors having crucial functions in T helper cell and B-cell responses. After stimulation follicular... 

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