Early stages of B cell development occur in the bone marrow, resulting in formation of immature B cells. From there these immature cells migrate to the spleen where they differentiate to mature cells. This final maturation step is crucial for the B cells to become responsive to antigens and to participate in the immune response. Recently, invariant chain (Ii), a major histocompatibility complex...

Antibody production and affinity maturation are driven by B cell extraction and internalization of antigen from immune synapses. However, the extraction mechanism remains poorly understood. Here we develop DNA-based nanosensors to interrogate two previously proposed mechanisms, enzymatic liberation and mechanical force. Using antigens presented by either artificial substrates or live cells, we ...

Generation of potent antibodies by a mutation-selection process called affinity maturation is a key component of effective immune responses. Antibodies that protect against highly mutable pathogens must neutralize diverse strains. Developing effective immunization strategies to drive their evolution requires understanding how affinity maturation happens in an environment where variants of the s...

Here, we describe a new approach designed to monitor the proteolytic activity of maturing phagosomes in live antigen-presenting cells. We find that an ingested particle sequentially encounters distinct protease activities during phagosomal maturation. Incorporation of active proteases into the phagosome of the macrophage cell line J774 indicates that phagosome maturation involves progressive fu...

Dendritic cells (DC) are professional antigen-presenting cells which are strategically positioned at the boundaries between the inner and the outside world, in this way bridging innate and adaptive immunity. DC can initiate T cell responses against microbial pathogens and tumors due to their capacity to stimulate naïve T cells. The development of DC occurs in distinct stages. DC precursors deve...

background and objective: evaluation of tumor proliferative activity may provide a predicting parameter to estimate biologic aggression and a subsequent prognosis that has been evaluated in many malignancies. we have selected renal cell carcinoma (rcc) in this study. to determine tumor proliferative activity, ki67 antibody was applied and results were compared with apoptosis, applying p53 antib...

conclusions the results revealed that the novel multi-epitope dna construct could be an effective candidate in tuberculosis vaccine development, and it is qualified to investigate its potential to induce cd4 and cd8 t- cell immune response in the experimental animal model. results mhc class i-and class ii-predicted epitopes showed a high potential to binding to human hlas alleles, with global b...