A common method of determining the role of specific
signaling molecules during
lymphocyte development is to generate a
transgenic mouse. This procedure, while informative, is time consuming, expensive and ultimately does not guarantee a defined answer. Here we present a protocol in which the
in vivo effects of a
gene of interest on both B and T
lymphocyte development may be determined simultaneously in a relatively short time period. This is achieved by introducing a defined
gene, such as a wild-type or mutated
signaling molecule, into a lymphoid progenitor population by retroviral
infection. The retrovirus generates a bicistronic message encoding the
gene of interest and
GFP, thus enabling identification of retrovirally transduced
cells in subsequent
lymphocyte lineages. The
cells are then introduced into
mice deficient for recombinase activating
gene 1 (Rag-/-
mice), thus allowing the development of donor-derived B and T lymphocytes
in vivo. Using this
technique, results can be obtained within 3-8 weeks.