Synovial fluid CD34⁻ CD44⁺ CD90⁺ mesenchymal stem cell levels are associated with the severity of primary knee osteoarthritis.

To the best of our knowledge, no reports have directly compared synovial fluid (SF)- and synovial membrane (SM)-derived mesenchymal stem cells (MSCs) from primary knee osteoarthritis patients in terms of MSC proportion, either immediately after isolation or during culture. Any possible correlation between SM- and SF-MSC purity and osteoarthritis severity, also remains unclear. We therefore assessed quantitative and phenotypic differences in MSCs isolated from SF and SM. We also evaluated the correlation between sample MSC purity, and disease severity, in patients with osteoarthritis. The main result of the current study was that the mean SF-MSC proportion at passage 0 was negatively correlated with Kellgren-Lawrence (KL) grade (r = -0.565, P = 0.002). In addition, KL grade was a only significant independent negative predictor of SF-MSC proportion at passage 0 (ß = -0.356, P = 0.039). Conclusively, the proportion of SF-MSCs in fresh samples, evaluated at the single cell level, was inversely correlated with osteoarthritis severity.

Oncolytic adenovirus co-expressing IL-12 and IL-18 improves tumor-specific immunity via differentiation of T cells expressing IL-12Rß2 or IL-18Rα.

The oncolytic adenovirus (Ad) is currently being advanced as a promising antitumor remedy as it selectively replicates in tumor cells and can transfer and amplify therapeutic genes. Interleukin (IL)-12 induces a potent antitumor effect by promoting natural killer (NK) cell and cytotoxic T cell activities. IL-18 also augments cytotoxicity of NK cells and proliferation of T cells. This effect further enhances the function of IL-12 in a synergistic manner. Therefore, we investigated for the first time an effective cancer immunogene therapy of syngeneic tumors via intratumoral administration of oncolytic Ad co-expressing IL-12 and IL-18, RdB/IL-12/IL-18. Intratumoral administration of RdB/IL-12/IL-18 improved antitumor effects, as well as increased survival, in B16-F10 murine melanoma model. The ratio of T-helper type 1/2 cytokine as well as the levels of IL-12, IL-18, interferon-γ and granulocyte-macrophage colony-stimulating factor was markedly elevated in RdB/IL-12/IL-18-treated tumors. Mice injected with RdB/IL-12/IL-18 also showed enhanced cytotoxicity of tumor-specific immune cells. Consistent with these results, immense necrosis and infiltration of NK cells, as well as CD4+ and CD8+ T cells, were observed in RdB/IL-12/IL-18-treated tumor tissues. Importantly, tumors treated with RdB/IL-12/IL-18 showed an elevated number of T cells expressing IL-12Rß2 or IL-18Rα. These results provide a new insight into therapeutic mechanisms of IL-12 plus IL-18 and provide a potential clinical cancer immunotherapeutic agent for improved antitumor immunity.

Tumor cells expressing membrane-bound form of IL-4 induce antitumor immunity.

Local cytokine concentrations are required for inhibition of tumor growth with less toxic side-effects. However, genetically engineered tumor cells secreting cytokines still induce toxicity and activate bystander cells. To circumvent such problems, membrane-bound forms of IL-4 (IL-4m) were expressed on MethA fibrosarcoma tumor cells. Chimeric forms of IL-4 with the type I transmembrane protein CD4 or type II transmembrane protein TNF were designed to express IL-4 in opposite orientations on the tumor cell surface. The IL-4m on tumor clones was able to support cell growth of the IL-4 dependent cytotoxic cell line (CT.4S) and the Th2 cell clone (D10). Furthermore, the IL-4m tumor clones stimulated proliferation of 2C TCR transgenic spleen cells which are responsive to Ld MHC class I molecules. Expression of the IL-4/TNF chimeric protein on MethA cells elicited antitumor immunity and protected from MethA tumor challenge. The proposed tumor vaccine may serve as an effective gene therapy method to avoid the toxicity of recombinant cytokines and bulk bystander leukocyte stimulation encountered in conventional cytokine gene therapy.

Investigation of influence of Proteus mirabilis LPS polysaccharide part on the murine immune cells activation.

The biological activities were investigated of Proteus mirabilis lipopolysaccharides (LPSs) and their fragments, namely, the induction of nitric oxide (NO) and interleukin 1 (IL-1) synthesis by murine macrophages and the proliferation of murine spleen cells. The O-specific polysaccharide (F1), core oligosaccharide (F2) and lipid A were as effective as intact LPS in stimulating murine macrophages to produce NO. IL-1 synthesis was also induced by all studied types of endotoxins (S, Ra, Re) and partial structures, however F1, F2 and lipid A fractions required the presence of serum. In contrast to LPS, the O-specific polysaccharide, core oligosaccharide and lipid A were not able to induce the blast response of murine non-adherent splenocytes.