An aspect of immunity involves the function of B lymphocytes (or B cells) that secrete antibodies. A protein expressed on B cells and other immune cells (CD40) is crucial for normal B cell action. CD40 interacts with a protein (CD40L) present on T cells that also contributes to B cell stimulation. This CD40-CD40L interaction is important for normal immune function. However, exaggerated B-cell responses to CD40 occur in autoimmune diseases such as multiple sclerosis. It has been shown that B cells from patients with relapsing-remitting multiple sclerosis (RRMS) are stimulated by CD40 to multiply significantly more than in healthy patients.
Nearly 7 million people in the U.S. (about 2% of the total U.S. population) suffer some level of stroke-related brain damage and related health problems. Studies in animals suggest that cell-based therapies can improve post-stroke outcomes. To determine the safety of cell-therapy approaches in humans, researchers from Stanford University conducted a clinical trial to study the safety of a procedure to transplant donor stem cells in the brains of patients with chronic stroke.
There are two broad populations of B cells, B-1 and B-2. B-1 cells are the primary B cell during fetal and neonatal development. These cells can self-renew and localize mainly in the peritoneal and pleural cavities. B-1 cells produce the majority of “natural” antibodies, immunoglobulin (Ig) M and IgA. Natural antibodies exist in the blood of healthy individuals before immunization, are the first line of defense against pathogens (disease-causing antigens), and they also influence T cell expansion.
The immune system consists of cells and factors that work to protect an organism from antigens (foreign cells or substances). T lymphocytes (T cells) are one group of cells that play important roles in immunity. Dendritic cells are another important group of immune cells that process the antigens for T cells. Not only do dendritic cells help T cells to act upon antigens, they aid in T cells’ tolerance of the body’s own cells. They do this by helping the T cells to distinguish between invading organisms and the body’s cells and molecules, between self and nonself. This role of dendritic cells helps protect the body from autoimmune attack by its T cells. Therefore, dendritic cells play key and essential roles in the direction and control of appropriate T cell responses.
Depression is a common and challenging component of Parkinson’s disease (PD). Up to 70% of patients with PD experience depression. This clinical symptom is not only a result of PD, but a part of the condition itself. Study findings have shown that inflammation not only plays a part in the physical signs of PD, but is also involved in the development of depression. The increase in inflammatory mediators, such as cytokines, in PD is detectable before signs of PD begin. These mediators may serve as important biomarkers of PD that can be utilized to detect PD and allow early intervention.