Changes Caused in the Homing Patterns of Chromium 51-Labeled Lymphoid Cells by Moloney Sarcoma Virus Infection

Abstract

The homing properties of murine lymphoid cells changed significantly during the course of Moloney murine sarcoma virus (MuSV-M) tumor induction, growth, and regression. When ⁵¹Cr-labeled spleen cells from BALB/c donors with progressing MuSV-M-induced tumors were injected into normal syngeneic recipients, a reduced content of spleen-seeking cells was observed, whereas similar preparations from animals with regressing tumors exhibited elevated percentages of spleen-seeking cells. The percentage of spleen-seeking cells contained in the lymph nodes of donors bearing MuSV-M-induced tumors increased in both instances. The homing of thymus or bone marrow cells was unchanged by MuSV-M infection. When the migration of spleen cells from MuSV-M-inoculated donors was studied as a function of time, the spleen-seeking populations returned to normal levels by day 15 after an initial increase from day 3 to 8. If the tumor progressed further, an additional decrease ensued, whereas the spleen-seeking population of donors with regressing tumors returned to above-normal levels. The lymph node-seeking population of the spleen and lymph nodes also declined when MuSV-M-induced tumors grew progressively. When MuSV-M-immune spleen cells were injected iv into MuSV-M-challenged recipients, significant early migration of such cells to recipient spleens was observed. Trapping of labeled splenocytes from normal donors was generally delayed. Increased sequestration of both immune spleen and lymph node cells in the lymph nodes of MuSV-M-infected recipients also occurred. The migration of both immune and normal lymph node cells to the spleens of MuSV-M-inoculated recipients was about equivalent, which suggested both specific and nonspecific elements in the response to MuSV-M. Athymic mice were also responsive to MuSV-M. When ⁵¹Cr-labeled spleen cells from MuSV-M-inoculated nu/nu donors were injected into normal mice, a sustained and significant increase in the percentages of spleen-seeking cells was observed. The data suggested that the response to MuSV-M involved both T- and B-lymphocyte recognition.