The Effect of Localized Injection of Adjuvant Material on the Draining Lymph Node

Abstract

Abstract The adjuvant effects of killed Bordetella pertussis organisms on the immune response to heterologous γ globulin was studied in normal, “T-cell-depleted” (thymectomized, irradiated, bone-marrow reconstituted) and thymus-marrow chimeric CBA mice. Incorporation of B. pertussis with alum-precipitated equine γ globulin (EGG) as antigen potentiated the anti-EGG antibody response in normal mice, but not in T-cell depleted animals. The draining lymph nodes of normal animals injected in the hind footpad with alum-precipitated bovine γ globulin (alum-BGG) showed a gradual rise in weight, followed by an increase in DNA synthetic activity as judged by uptake in the node of 125I-labeled 5-iodo-2-deoxyuridine (IUDR). Normal animals given pertussis-incorporated antigen showed an accelerated and augmented lymph node weight increase, and a higher peak of DNA synthesis. In T-cell-depleted animals, lymph node weight and IUDR uptake were only slightly increased after alum-BGG, and were not further enhanced by using alum-BGG-pertussis. Mitoses were more numerous in the draining nodes of CBA/HT6T6-CBA/H thymus-marrow chimeras given alum-BGG-pertussis than in such animals given alum-BGG only. At any given time during the response, however, the ratio of thymus-derived to marrow-derived mitoses was approximately the same in the two groups. Normal mice given alum-BGG-pertussis showed histologic hyperplasia of the paracortical regions of draining lymph nodes, with increased numbers of small lymphocytes. In T-cell-depleted animals, paracortical hyperplasia occurred without a significant increase in colonizing small lymphocytes. The data suggest that B. pertussis organisms act to augment the recruitment of recirculating thymus-derived cells to the paracortical regions of draining lymph nodes, and that subsequent cellular proliferation in the node is in part determined by the magnitude of this recruitment.