Objectives: We have engineered a transgenic/double knockout mouse strain that allows us to study the TI-2 immune response to a specific TI-2 antigen in detail, in the absence of other simultaneous immune responses. This new inbred strain of mouse, called PV1TgL, can only make a single species of immunoglobulin, an IgM/lambda derived from a hybridoma, PV1, secreting antibody reactive wit the synthetic polymer polyvinyl pyrrolidinone.
We have used this new strain of mouse to ask the following questions: 1. What is the role of exogenous antigen in the development of B lymphocytes? 2. After immunization, in what lymphoid organs do antibody-secreting cells appear and in what order do they appear in those organs? 3. What are the phenotypic characteristics of mature B cells that appear in the peripheral lymphoid organs as the result of specific immunization?
Methods: Through conventional serological analysis, ELISAspot enumeration of individual antibody-secreting cells, and cell-surface antigen analysis using Flow Cytometry, we have produced the following answers to those questions:
Results: and Conclusions: 1. In the absence of antigen, B lymphocytes develop to the late transitional, immature B cell stage, i.e. antigen is necessary for the development of mature B lymphocytes. 2. After immunization, a population of B lymphocytes appears in the spleen with the phenotypic characteristics of B-1 lymphocytes, a minority subset of B cells previously thought to arise only in fetal and neonatal life.
This work was supported by grant P60-DE-13079 to the Comprehensive Center for Inflammatory Disorders.