Rosette Formation: a Tool for T-lymphocyte Enume- Ration and Assessment of Innate Immunity

Rosettes formation technique (SRBC) was employed for the assessment of lymphocyte per cent. Development of accurate methods for enumeration of T and B lymphocytes in human and animal peripheral blood during the past decades has led to a plethora of papers on T and B lymphocytes in various pathologic states. Lymphocytes can be divided into T and B lymphocytes on the basis of selective binding capacity of T-lymphocytes with Sheep RBC (SRBC). On the basis of enumeration of T-lymphocyte innate immunity status of Non-discript (ND) and Sahiwal (S) cattle was compared. Rosette forming T-lymphocytes were enumerated in all the four groups of animals. The mean (±SE) values of T-lymphocytes (per cent) in ND-I, ND-II, S-I and S-II was 41.04±0.47, 56.83±0.99, 35.79±0.93 and 56.62±0.76, respectively. A comparative study on Tlymphocytes showed that there was significant increase (P<0.01) in T-lymphocytes count with respect to age in both breeds. The T-lymphocytes count of ND calves was significantly (P<0.01) high when compared with Sahiwal calves whereas breed difference was not observed in adult animals.