Characterization of dog interleukin-2 activity

Bulk cultures of canine peripheral blood lymphocytes with solid phase anti-CD3 antibody and recombinant interleukin-2 for use in immunotherapy

Interleukin (IL)-2 can induce large numbers of lymphokine-activated killer cells in peripheral blood lymphocytes (PBL), but IL-2 alone cannot induce proliferation of a large number of canine (c) PBL. We used the solid phase anti-CD3 antibody and soluble recombinant (r) IL-2 in order to establish a large scale culture method for cPBL. The number of lymphocytes seeded (3 x 10 (7)) increased to 1 x 10(9) after incubation for 10 days. The phenotype of cultured cPBL cells (after 2 weeks) showed a CD4(+) or CD8(+) predominant cell population. The cultured cell solutions were administered with physiological saline intravenously to each dog. After transfusion of the cultured cells, the cPBL counts, especially the number of CD4(+), CD8(+) and CD4(-)CD8 (-)(DN) cells increased significantly in the recipient dogs. Natural killer (NK) cells, gammadeltaT cells and B cells were considered to be present in the DN cell population. The NK cells and gammadeltaT cells showed no adverse reaction to the transfusion of the activated cPBL. Therefore, it is necessary to recognize the B cells present in the DN cell population by detecting CD21(+) cells. In conclusion, the bulk culture system of cPBL with rIL-2 and solid phase anti-CD3 antibody may be useful for the development of novel immunotherapy in dogs.

Expression of interleukin-1 beta, interleukin-6 and tumour necrosis factor alpha by macrophages in canine lymph nodes with mineral-associated lymphadenopathy, granulomatous lymphadenitis or reactive hyperplasia

The distribution of CD3+ T lymphocytes and the expression of interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF alpha) by macrophages in canine lymph nodes with mineral-associated lymph-adenopathy, granulomatous lymphadenitis or reactive hyperplasia was examined immunohistochemically. In areas of preserved lymph node architecture, CD3+ T lymphocytes were located in the paracortex, with scattered cells in the follicular mantle and germinal centre, and small aggregates in the medullary cords. T cells were prominent within areas of diffuse granulomatous inflammation and formed a peripheral rim around microgranulomas. TNF alpha expression was demonstrated in macrophages from seven of 11 dogs with mineral-associated lymphadenopathy, one of five dogs with granulomatous lymphadenitis and three of five with reactive hyperplasia. Positive macrophage staining for IL-1 beta and IL-6 was seen in two lymph nodes with reactive hyperplasia. Lymph nodes from control (clinically normal) dogs showed no evidence of cytokine expression. Neutrophils expressing IL-1 beta were observed within the medullary sinuses of two lymph nodes with mineral-associated lymphadenopathy and one with reactive hyperplasia, and in the inflammatory infiltrate in one lymph node with granulomatous lymph-adenitis. The sensitivity of immunohistochemical examination as a means of detecting cytokines in abnormal tissue is discussed.