Transfer of maternal colostral leukocytes promotes development of the neonatal immune system Part II. Effects on neonatal lymphocytes.

It has been established that maternal leukocytes, conditioned by the mammary environment, cross the neonatal gut and circulate in the newborn calf. However, the impact of these cells on the development of neonatal immunity remains to be determined. This study examined the effects of maternal colostral leukocytes on development and maturation of neonatal adaptive immunity by examining the expression of surface markers on neonatal lymphocytes. At birth, neonatal calves were fed whole colostrum, or colostrum that had the maternal cells removed (cell-free colostrum), from their respective dams. Peripheral blood samples were collected at regular intervals over the first 4 weeks of life and lymphocytes were evaluated for surface expression of cellular markers. The results of these studies demonstrated that calves receiving whole colostrum had fewer CD11a positive lymphocytes in circulation during the first 2 weeks of life and this marker was expressed at a lower density than calves receiving cell-free colostrum. In addition, calves receiving whole colostrum also had a higher percentage of lymphocytes expressing the activation markers CD25 and CD26 by 7 days after birth. During the first week of life, lymphocytes from calves receiving whole colostrum had a higher density of MHC class I expression on their surfaces than cells from calves receiving cell-free colostrum. In general, these results indicate that transfer of maternal cells with colostrum allows for more rapid development of lymphocytes and maternal cells appeared to enhance their activation.

Transfer of maternal colostral leukocytes promotes development of the neonatal immune system I. Effects on monocyte lineage cells.

Although it has been established that maternal leukocytes traffic from colostrum into the neonatal circulation, the effects of these cells on neonatal immunity are only beginning to be understood. This study examined the effects of maternal colostral leukocytes on development and maturation of neonatal antigen presenting cells. At birth, groups of neonatal calves received whole or cell-free colostrum (CFC) from their respective dams. Peripheral blood samples were obtained over the first 4 weeks of life, and expression of surface markers associated with cellular activation and physiological stress were monitored on monocyte lineage cells. Calves receiving cell-free colostrum at birth expressed elevated levels of CD11a, CD11c, and CD14, compared to calves receiving whole colostrum (C). Calves receiving cell-free colostrum had an elevated number of monocytes in the peripheral blood during the first 2 weeks of life, however, these cells expressed lower levels of expression of CD25 and MHC class I compared to calves receiving whole colostrum. The most significant differences in marker expression occurred within the first 7 days of life.

Values of the U.S. National Reference Serum for human antibodies to native DNA obtained with commercial immunoassays for anti-DNA in systemic lupus erythematosus.

The Arthritis Foundation and the Centers for Disease Control have recently prepared a "U.S. National Reference Serum" for human antibodies to native DNA. We tested this serum with 13 commercial assays for antibodies to native DNA, to permit comparisons of the values obtained in each test. Titers ranged from 10 to 2560 in Crithidia luciliae immunofluorescence assays. The serum produced 794 int. units/mL in the Cordis ELISA assay, 136 Amersham units/mL in a radioimmunoassay, and 88 FIAX units in a fluorometric immunoassay. These results can be used for interlaboratory comparisons of differing methodologies for measuring anti-DNA.