Immune response of armadillos (Dasypus novemcinctus). I. Use of lectins to identify lymphocyte subpopulations and to evaluate cell proliferation

Lectins have been used to study populations and discrete differentiation stages of lymphocytes. Likewise, lectins have been of practical importance in promoting mitogenic stimulation of lymphocytes in numerous species. In this research project, we took advantage of these tools in an attempt to identify specific subsets of peripheral blood lymphocytes obtained from healthy nine- banded armadillos (Dasypus novemcinctus). The same cell source served to evaluate mitogenic stimulation. Twelve FITC-labeled lectins were used; 5 (ConA, LcH, RCA, WGA and UEA) reacted with almost 100% of the lymphocytes and 7 (PNA, DBA, SBA, PCA, PHA-L, PWM and VVA) recognized variable percentages (<100% of these cells). This latter group of lectins may be useful in the identification of armadillo lymphocyte subsets, or may correlate with discrete stages of differentiation of these cells. The same lectins served to evaluate mitogenic stimulation in an aliquot of the same peripheral blood mononuclear cells. Of the 12 lectins studied, 5 (ConA, PHA-L, PWM, DBA and SBA) had the capacity to induce mitogenic stimulation in the whole mixture of mononuclear cells, giving rise to variable degrees in the corresponding mitogenic index obtained for each of the 5 lectins. Those lectins that gave an indication of selective identification of lymphocytes, that is, the percentages at or below 75%, may prove useful in the evaluation of the immune response of healthy armadillos as well as the evolution of progression stages of lepromatous leprosy in armadillos inoculated with the same strain of Mycobacterium leprae that affects humans.