Selective DNA synthesis by cells specifically localizing in response to xenogeneic erythrocytes

Accumulation of plasma cells in inflamed sites: effects of antigen, nonspecific microbial activators, and chronic inflammation

Plasma cells are common in chronically inflamed sites, including periodontal lesions. The aim of this study was to determine which factors contribute to this local accumulation of plasma cells. Specifically, we sought to evaluate the effects of specific antigen and nonspecific activators from an infectious agent associated with chronic inflammation (Fusobacterium nucleatum, an organism prominent in chronic periodontal lesions) and the effect of the chronic inflammation itself. Chronic inflammation (14 to 17 days) was induced in horseradish peroxidase (HRP)-immune rabbits by subcutaneous injection of 50 microliters of sterile alum in several sites in their backs. Controls included sites injected with saline or more acute sites examined after 3 days of alum inflammation. Sites were challenged with HRP (the antigen), sonicated F. nucleatum (the nonspecific activator), or both together to see whether F. nucleatum has an adjuvant effect. Three days after challenge, HRP-specific antibody-forming cells (AFC) were enumerated after peroxidase histochemistry. In noninflamed sites or sites with acute inflammation, virtually no HRP-specific AFC were evident. In contrast, chronic inflammation alone was sufficient to elicit a specific AFC response (congruent to 10 cells per mm2). Addition of either F. nucleatum or HRP to the chronic lesion about doubled the number of HRP-specific AFC. However, a dramatic 8- to 15-fold (80 to 150/mm2) increase was seen in chronically inflamed sites challenged with antigen and activator together. Interestingly, the activator did not have this adjuvant effect in the acute sites or in normal skin. In short, accumulation of plasma cells in inflamed sites is promoted by chronic inflammation, activators of microbial origin, and specific antigen. This milieu can be expected to develop in some periodontal lesions and could help explain why gingival crevicular fluid from some sites may contain extraordinary levels of locally produced specific antibodies for certain antigens.

Delayed-type hypersensitivity to rabies virus in mice: assay of active or passive sensitization by the footpad test

With a purified beta-propiolactone-inactivated rabies virus, a significant increase in footpad swelling was elicited in normal or in BCG-pretreated mice after immunization with varying doses of rabies vaccine. These footpad reactions were shown to peak at 24 h and to be associated with an infiltration of newly formed blood monocytes demonstrated by histology and [125I]deoxyuridine labeling. A relationship between the lymphoproliferation and the degree of sensitization is described, and the susceptibility to cyclophosphamide treatment is also examined. Adoptive transfer of specific reactivity to normal recipient mice with immune lymphoid cells, but not with immune serum, was demonstrated, and the results represent another argument for a cell-mediated immunological mechanism.

Migratory behavior of lymphocytes with specific reactivity to alloantigens. II. Selective recruitment to lymphoid cell allografts and their draining lymph nodes

A dual-antigen, dual-isotope assay has been used to monitor the migratory behavior of selectively labeled antiallogeneic lymphocytes in mice challenged subcutaneously in all four foot pads with semiallogeneic spleen cells. 3H-labeled anti-C3H and 14C-labeled anti-C57BL lymphocytes of DBA/2J origin were pooled and adoptively transferred to multiple groups of previously challenged DBA/2J recipients. In some of the studies, separate groups of recipients were challenged with either CDF or BDF spleen cells in all four paws, whereas in others CDF spleen cells were used to challenge the right paws of each mouse in the group and BDF spleen cells to challenge the left paws of each mouse in the group. At intervals varying from 24 to 96 h after challenge, a subgroup of four mice from each appropriate group was sacrificed and the relative numbers of anti-C3H and anti-C57BL lymphocytes present in the challenged paws, draining lymph nodes, and other tissues of each mouse were inferred from the mean 3H/14C ratios of the respective tissues of that subgroup. The results of these studies firmly establish that specific antiallogeneic lymphocytes are selectively recruited to the paws and draining lymph nodes of mice challenged subcutaneously in the foot pads with semiallogeneic spleen cells and are deleted from their circulating blood and nondraining lymph nodes. A mechanism for antigen-induced selective recruitment and its possible functional significance in tumor immunology are discussed.

Competition for cytotoxic immune capacity against a 'syngeneic' mouse tumour distributed at two sites

Normal C3H mice will develop fatal ascites after the intraperitoneal injection of as few as 100 BP8 cells. However, mice can be immunized so that they can specifically reject an intraperitoneal challenge of 10(7) of these C3H-derived tumour cells. This paper investigates a phenomenon in which the capacity of immunized mice to reject an intraperitoneal challenge of tumour cells is lost between two to seven days after tumour cells have been given subcutaneously. Investigation of this temporary loss of capacity to reject the intraperitoneal challenge of tumour suggests that this might be due to the attraction of cytotoxic immunity to the site of subcutaneous injection. The possibility that this phenomenon is due to blocking factors, tumour overload, suppressor cells or enhancing antibody has been investigated but experimental results are given which do not favour these explanations.