No abstract

To demonstrate the intra- and extracellular localization of hyaluronic acid (HA) in articular cartilage of the rabbit tibia, biotinylated HA binding region, which specifically binds to the HA molecule, was applied to the tissue. In comparison with the localization of HA, that of chondroitin sulfate (CS), keratan sulfate (KS), and the protein core (PC) of the proteoglycan was examined by immunohistochemistry. Strong positive staining for HA was detected in chondrocytes located in the transition between the superficial and middle zones of the tissue. Pre-treatment with chondroitinase ABC, keratanase II, or trypsin enhanced the stainability for HA in peri- and intercellular matrices. Immunohistochemistry with or without enzymatic pre-treatment demonstrated that immunoreactivity for CS, KS, and PC was distinctly discerned in chondrocytes and in the extracellular matrix located in the middle and deep zones. In particular, the immunoreactivity for KS and PC was augmented by pre-treatment with chondroitinase ABC not only in chondrocytes but in the extracellular matrix located in the middle and deep zones. Microbiochemical analysis corresponded well with histochemical and immunohistochemical results. These results suggest that HA is abundantly synthesized and secreted in chondrocytes located in the transition between the superficial and middle zones.

ABSTRACT-Chondroitin sulfate (CS) is currently marketed as a therapeutic drug for neurodynia, lumbago and arthrodynia. Recently, many clinical studies have demonstrated the therapeutic effects of orally administered CS against diseases with inflammation. Furthermore, these reports suggest CS plays an important role in the protection of the base of ulcers and has anti-inflammatory activity. We investigated the effects of CS against dextran sulfate sodium (DSS)-induced rat colitis. Rats were given 3% DSS solution for 10 days ad libitum. CS and 5-aminosalicylic acid (5-ASA) were orally administered daily. The doses of the CS groups were 20 or 100 mg/kg and that for the 5-ASA group was 100 mg / kg. Evaluations were made of bloody stools, areas of erosion and hematological data. CS improved the symptoms of bloody stools, erosion and increase of white blood cells. Especially, CS (100 mg/ kg) group showed markedly more improvement than the 5-ASA group. We think that the major mechanism of the therapeutic effects of CS are the prevention of tissue damage by the protection of digestive mucosa and anti-inflammatory effects. Therefore, CS may have therapeutic value for alimentary tract diseases such as inflammatory bowel disease or ulcer.

Autologous stem cell transplantation (ASCT), with subsequent lenalidomide maintenance is standard consolidation therapy for multiple myeloma and a subset of patients achieve durable progression-free survival that is suggestive of long-term immune control. Nonetheless, most patients ultimately relapse, suggesting immune escape. TIGIT appears a potent inhibitor of myeloma-specific immunity and represents a promising new checkpoint target. Here we demonstrate high expression of TIGIT on activated CD8 T cells in mobilized peripheral blood stem cell grafts from patients with myeloma. To guide clinical application of TIGIT inhibition, we evaluated identical TIGIT Abs that do or do not engage FcγR and demonstrated that anti-TIGIT activity is dependent on FcγR binding. We subsequently used CRBN mice to investigate the efficacy of anti-TIGIT in combination with lenalidomide maintenance after transplantation. Notably, the combination of anti-TIGIT with lenalidomide provided synergistic, CD8 T cell-dependent, antimyeloma efficacy. Analysis of bone marrow (BM) CD8 T cells demonstrated that combination therapy suppressed T cell exhaustion, enhanced effector function, and expanded central memory subsets. Importantly, these immune phenotypes were specific to the BM tumor microenvironment.Collectively, these data provide a logical rationale for combining TIGIT inhibition with immunomodulatory drugs to prevent myeloma progression after stem cell transplantation.

To elucidate the potential role of superoxide (O2-) and nitric oxide (NO) in the pathogenesis of interstitial pneumonia, the quantity of O2- and NO produced by the alveolar macrophages (AM) were determined in the bleomycin (BLM)-induced interstitial pneumonia mouse model. The production of O2- and NO increased on days 7, 14 and 21 after BLM injection. Strong expression of peroxynitrite (ONOO-) was seen in AM by using immunostaining for nitrotyrosine. The hydroxyproline contents increased on day 21 after BLM injection. O2- and NO are thought to play an important role in the pathology of fibrosis.

ABSTRACT-Superoxide anion (02-) acts as an exacerbation factor in interstitial pneumonia. Lecithinized-superoxide dismutase (PC-SOD), which is synthesized with a lecithin derivative bound cova lently to recombinant human Cu,Zn-SOD, has a longer half-life in plasma and higher affinity to cell mem branes than unmodified SOD. The effect of PC-SOD was evaluated using the bleomycin-induced interstitial pneumonia mouse model. Treatment with PC-SOD at 10 mg/kg significantly reduced the hydroxyproline content and fibrosis score. Namely, PC-SOD suppressed the progression of pulmonary fibrosis on the bleomycin-induced interstitial pneumonia mouse model. PC-SOD may be a potential drug for interstitial pneumonia therapy.

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is a potentially curative therapy for FLT3 internal tandem duplication mutant (FLT3-ITD + ) acute myeloid leukemia, but relapse rate is high. A recent study showed that sorafenib, a first generation FLT3 and multikinase inhibitor, enhanced graft-versus-leukemia (GVL) effects against FLT3-ITD + leukemia via interleukin-15 (IL-15) production. However, it remains to be clarified whether this effect could be mediated by selective FLT3 inhibition. We investigated whether gilteritinib, a selective FLT3 inhibitor, could enhance GVL effects against FLT3-ITD transfected Ba/F3 leukemia (Ba/F3-FLT3-ITD) in mice. Oral administration of gilteritinib from day +5 to +14 after allo-SCT reduced expression of the co-inhibitory receptors PD-1 and TIGIT on donor CD8 + T cells and enhanced IL-15 expression in Ba/F3-FLT3-ITD. Bioluminescent imaging using luciferase-transfected Ba/F3-FLT3-ITD demonstrated that gilteritinib significantly suppressed leukemia expansion after allo-SCT, whereas it did not impact the morbidity or mortality of graft-versus-host disease (GVHD), resulting in significant improvement of overall survival. In conclusion, short-term administration of gilteritinib after allo-SCT enhanced GVL effects against FLT3-ITD + leukemia without exacerbating GVHD.

Apheresis in low body weight children and adoles-