The Suckling Rat as a Model for Immunonutrition Studies in Early Life

Figure 1

Developmental pattern of the systemic immune system in rats from suckling to adult age. Spleens of Lewis rats were obtained at several time points during suckling and, after mechanical spleen disruption, splenocytes were isolated by density gradient. Cells were stained by fluorochrome-conjugated monoclonal antibodies directed against several lymphocyte surface molecules (CD45RA for B cells, TCRαβ for T cells and NKR-P1A for NK cells). The percentage of each subset was established by flow cytometry analysis. Other splenocytes were incubated in presence of Concanavalin A or pokeweed mitogen over 72 h and proliferating cells were identified by means of a cell proliferation assay [24]. (a) Main spleen lymphocyte subsets during suckling in Lewis rats (expressed as a percentage of total spleen lymphocytes). (b) Proliferative response of neonatal spleen cells with concanavalin A (T-cell proliferation) and pokeweed mitogen (B-cell proliferation) in comparison with adult Lewis rats (which is considered as 100%). Results are estimated from data obtained from 1, 3, 5, 7, 11, 14, and 21-day-old rats (modified from [24]).