Porcine circovirus type 2 (PCV2) induces cell proliferation, fusion, and chemokine expression in swine monocytic cells in vitro

Granulomatous lymphadenitis is one of the pathognomonic lesions in post-weaning multisystemic wasting syndrome (PMWS)-affected pigs. This unique lesion has not been reported in direct association with viral infection in pigs. The objective of the present study was to evaluate whether porcine circovirus type 2 (PCV2) alone is able to induce functional modulation in porcine monocytic cells in vitro to elucidate its possible role in the development of granulomatous inflammation. It was found that the proliferation activity of blood monocytes (Mo) and monocyte-derived macrophages (MDM) was significantly enhanced by PCV2. During monocyte-macrophage differentiation, the PCV2 antigen-containing rate and formation of multinucleated giant cells (MGC) were significantly increased in MDM when compared to those in Mo. The MDM-derived MGC displayed a significantly higher PCV2 antigen-containing rate than did the mono-nucleated MDM. Supernatants from PCV2-inoculated MDM at 24 h post-inoculation induced an increased tendency of chemotactic activity for blood Mo. At the same inoculation time period, levels of mRNA expression of the monocytic chemokines, monocyte chemoattractant protein-1 and macrophage inflammatory protein-1, also significantly increased in PCV2-inoculated MDM. The results suggest that PCV2 alone may induce cell proliferation, fusion, and chemokine expression in swine monocytic cells. Thus, PCV2 itself may play a significant role in the induction of granulomatous inflammation in PMWS-affected pigs

Aging and the Immune System: Age-Related Changes of Lymphocyte Functions in Mice and Effects of Immunologic Manipulations on the Aging Process

143 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1984.The nature of the age-related immunologic defects of BC3F1 mice was investigated in mice of various ages. Suppressor, T helper and B cell activities in the spleen were assessed. It was found that the suppressor function increased rapidly, reached a peak in middle-aged mice, and remained elevated thereafter. T helper and B cell functions declined at a constant rate with age. Attempts were then made to restore the immune function of senescent mice by appropriate immunotherapy. Adult BC3F1 mice were treated with anti-I-J monoclonal antibody, human dialyzable leukocyte extract (DLE), or saline weekly for 1 year. Spleen cells were assayed for suppressor, T helper and B cell activities. Organs were processed for pathologic study. It was found that treatment with DLE decreased the suppressor activity, while anti-I-J treatment elevated T helper activity. Both treatments slightly decreased the tumor incidence. In another study, the effects of these treatments on the immune response to avian gamma globulin and on lifespan were examined. Both treatments resulted in secondary antibody responses greater than those of control mice. Treatment with anti-I-J resulted in prolongation of life. There was a correlation between the magnitude of the secondary responses and lifespan. The results provide support for the immunologic theory of aging.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD