Interleukin-6 is required for pristane-induced plasma cell hyperplasia in mice.
Intraperitoneal injection of pristane induces production of interleukin-6 (IL-6) and either plasmacytosis or plasmacytoma in mice, depending upon the genetic background. Pristane does not induce plasmacytoma in IL-6 knockout (IL-6-/-) mice, suggesting that IL-6 is required for this process. In the present study we determined whether IL-6 is also required for pristane-induced hyperplasia of normal plasma cells. Pristane was injected intraperitoneally into IL-6-/- and IL-6 wild-type (IL-6+/+) mice. Overall there were more deaths in IL-6+/+ mice (85%) than in IL-6-/- mice (40%), P = 0.024. Hyperplastic lymph node and spleen weight did not differ (P = 0.82 and P = 0.15, respectively) in IL-6-/- versus IL-6+/+ mice. Lymphocytosis with similar patterns of expression of B-cell (B220) and T-cell (Thy-1) antigens was noted in both IL-6-/- and IL-6+/+ mice. However, morphological studies, dual fluorescent staining for Syn-1 and B220 antigens (syn-1+ B220+ cells), and intracytoplasmic Ig staining revealed plasma cell hyperplasia in lymph node and spleen from IL-6+/+, but not IL-6-/-, mice. These plasma cells from IL-6+/+ mice were polyclonal and unable to induce tumour formation in severe combined immunodeficient mice. These data demonstrate that IL-6 is required for pristane-induced hyperplasia of polyclonal plasma cells in mice.
Dedera
D A
DA
Division of Hematologic Malignancies, Dana Farber Cancer Institute, Boston, MA 02115, USA.
Urashima
M
M
Chauhan
D
D
LeBrun
D P
DP
Bronson
R T
RT
Anderson
K C
KC
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D005434:Flow Cytometry; D006965:Hyperplasia / Q000139:chemically induced / Q000473:pathology; D015850:Interleukin-6 / Q000009:adverse effects / Q000494:pharmacology*; D008198:Lymph Nodes / Q000473:pathology; D051379:Mice; D018345:Mice, Knockout; D010950:Plasma Cells / Q000187:drug effects / Q000473:pathology*; D010954:Plasmacytoma / Q000139:chemically induced / Q000473:pathology; D013154:Spleen / Q000473:pathology; D015996:Survival Rate; D013729:Terpenes / Q000009:adverse effects / Q000494:pharmacology*
D015850:Interleukin-6; D013729:Terpenes; C009042:pristane