Blastogenic response and immunoglobulin production by inflamed gingival lymphocytes from dogs

The present study evaluated blastogenic responses and immunoglobulin production (IgG, IgM) by inflamed gingival lymphocytes from dogs. The excised tissues were cut finely, digested in collagenase for 60 min, then passed through a mesh, teased with a 24 G needle several times and centrifuged over a ficoll gradient. Responses to PHA, Con‐A and PWM were assessed using peripheral blood lymphocytes (PBLs) and submandibular lymph node cells (SNLs) as controls. Blastogenesis was evaluated from the uptake of 3 H‐thymidine and the presence of IgG and IgM in culture supernatants was quantified using ELISA. The extraction procedure resulted in a mean 2.09 ± 0.44 × 10 5 lymphocytes per 100 mg tissue (wet weight). These cells had a mean viability of 84.4 ± 3.0%. The responses of PBLs and SNLs to PHA, Con‐A and PWM were substantial, as expected, while the responses of gingival lymphocytes to any mitogen remained at the level of unstimulated lymphocytes. However, gingival lymphocytes produced and secreted IgG and IgM. IgG production by gingival lymphocytes was elevated when compared with those of PBLs and SNLs, while IgM production by gingival lymphocytes was less than PBLs and SNLs. The responses of PBLs and SNLs are not parallel to the response of gingival lymphocytes.