Combination therapy with dendritic cell-based vaccine and anti-CD69 antibody enhances antitumor efficacy in renal cell carcinoma-bearing mice.

BACKGROUND/AIM: Dendritic cell-based vaccine therapy for renal cell carcinoma is effective but requires improvement. Here we explored whether combination therapy with dendritic cell-based vaccine and anti-CD69 antibody can enhance antitumor efficacy in renal cell carcinoma-bearing mice. MATERIALS AND METHODS: Balb/c mice were challenged subcutaneously with murine renal cell carcinoma (Renca) cells. On day 3 after tumor cell inoculation, tumor-bearing mice either were left untreated or were treated with Renca tumor lysate-pulsed dendritic cells (i.e. dendritic cell-based vaccine), anti-CD69 antibody, or a combination of Renca tumor lysate-pulsed dendritic cells with anti-CD69 antibody. The mice were sacrificed on day 28. Tumor volume was measured for analysis of antitumor efficacy. Spleens were excised to evaluate antitumor immunological responses by measuring the proliferation and activation of T cells, which have the capacity to recognize and destroy tumor cells. RESULTS: Combination treatment with Renca tumor lysate-pulsed dendritic cells and anti-CD69 antibody resulted in significant decreases in tumor volume and significant increases in T-cell proliferation and activity, compared with no treatment or either treatment alone. CONCLUSION: These findings indicate that anti-CD69 antibody can potentiate antitumor efficacy of dendritic cell-based vaccine. The augmented therapeutic efficacy conferred by the combination therapy may be associated with increased T-cell proliferation and activity.

Tendon tissue engineering with mesenchymal stem cells and biografts: an option for large tendon defects?

The most important factors in the tissue engineering approach to tissue repair and regeneration are the use of appropriate cells and scaffolds. Mesenchymal stem cells (MSCs) are one of the most promising seed cells, which can be easily derived and have the potential to differentiate into various mesenchymal cell types as well as tenocytes in vitro and in vivo. Biological tendon grafts are the most common choice in current clinical practice, as they possess physical structure, strength and biocompatibility. We review the latest research findings on MSC-based tendon tissue engineering and recent advances in biological graft research.

Ligament regeneration using a knitted silk scaffold combined with collagen matrix.

This study was aimed to develop a new practical ligament scaffold by synergistic incorporation of silk fibers, a knitted structure, and a collagen matrix. The efficacy for ligament tissue engineering was investigated in vitro and in animal models. Cells cultured on a collagen substrate expressed ligament matrix genes at higher levels than those on a silk substrate. The silk scaffold elicited little inflammatory reaction and degraded slowly after subcutaneous implantation in a mouse model. In the rabbit MCL defect model, MCLs treated with a silk+collagen scaffold deposited more collagen, had better mechanical properties, and showed more native microstructure with larger diameter collagen fibrils and stronger scaffold-ligament interface healing than untreated MCLs and those treated with silk scaffolds. These results demonstrated that the knitted silk+collagen sponge scaffold improves structural and functional ligament repair by regulating ligament matrix gene expression and collagen fibril assembly. The findings are the first to highlight the important roles of biomaterials in ligament regeneration biology. Also, the concept of an "internal-space-preservation" scaffold is proposed for the tissue repair under physical loading.

Aspirin can elicit the recurrence of gastric ulcer induced with acetic acid in rats.

UNLABELLED: This study was supported by grants of New Ideas Capability for Backbone Teachers in Universities of Heilongjiang and of Scientific Research foundation in Qiqihar Medical College. BACKGROUND/AIMS: Ulcer recurrence and poor healing may be critically important to the development of serious gastrointestinal complications in patients with long-term non-steroid anti-inflammatory drugs (NSAIDs). The present study is to investigate the effects of aspirin on ulcer recurrence and healing quality and to explore the mechanism. METHODS: Gastric ulcers were induced with acetic acid in rats; aspirin was administrated by gavage from day 25 to day 54 after ulcer induction. The gastric juice volume, pH, gastric mucus, gastric mucosal blood flow (GMBF) and prostaglandin E(2) (PGE(2)) were measured. The mRNA transcription of cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) were analyzed with RT-PCR and protein expression with Western blot. RESULTS: The gastric juice volume was significantly increased in aspirin group compared with those of fasting or saline control groups (P<0.01); while the pH, mucus, GMBF and PGE(2) were significantly decreased in aspirin treated rats compared with those of other two groups (P<0.01). COX-2, evaluated with mRNA and protein expression, was significantly augmented in aspirin group compared with others. The quality of ulcer healing (QOUH) in Aspirin group was poorer than that of fasting or saline control groups. CONCLUSIONS: Aspirin enhance the recurrence of gastric ulcer. The inhibition of cycloxygenase, mucus secretion and mucosal blood flow may be involved. Aspirin also impair the quality of ulcer healing.

A male reproduction-related Kazal-type peptidase inhibitor gene in the prawn, Macrobrachium rosenbergii: molecular characterization and expression patterns.

Peptidase inhibitors in the male reproductive tract are well known in mammals, in which they play roles in protecting the tract epithelium against proteolytic damage or in regulating the fertilization process. By screening the subtracted cDNA clones enriched for male reproductive tract-specific transcripts, one clone encoding a putative protein that showed significant similarity to Kazal-type peptidase inhibitor (KPI) was obtained. This is the first report of an invertebrate in which a male reproductive tract-specific KPI gene has been identified and characterized. The gene contains a 405-bp open reading frame (ORF), a 72 bp 5' untranslated region (UTR), and a 259 bp 3' UTR. The conceptually translated protein consisted of a 21-amino-acid signal peptide and a 113-amino-acid mature polypeptide with two Kazal-type domains (named after the discoverer). Significant levels of the mRNA were observed only in the male reproductive tract, while mRNA expression was not detected in any other tissues tested. The transcription of the gene remained constant during maturation, although not in the postlarval stage. In situ hybridization demonstrated the presence of the mRNA in the secretory epithelial cells of vas deferens and terminal ampullae.

Naturally occurring antisense RNA of allatostatin gene in the prawn, Macrobrachium rosenbergii.

Allatostatins are important regulatory neuropeptides which are widely distributed in invertebrates and execute their functions through either neural or humoral routes. However, the regulatory mechanism of the gene expression is unclear. In this paper, we report a naturally occurring antisense transcript, named as asMacro-AST A, of the crustacean FGLamide allatostatin gene (Macro-AST A) from the prawn, Macrobrachium rosenbergii. The asMacro-AST A contains an 843-bp sequence fully complementary to the 3' end of the Macro-AST A. To our knowledge, this is the first report of a natural antisense transcript in crustacean and the first endogenous antisense transcript of all identified allatostatin genes. Northern blotting analysis demonstrated that the gene was expressed in the thoracic ganglia where the sense gene was also expressed. Furthermore, we have detected a RNA-RNA duplex between the sense-antisense complementary region by using RNase protection analysis and RT-PCR. These results suggest that the antisense gene may play a role in the regulation of Macro-AST A gene expression.

Molecular cloning and characterization of FGLamide allatostatin gene from the prawn, Macrobrachium rosenbergii.

Allatostatins are important regulatory neuropeptides that inhibit juvenile hormone (JH) biosynthesis by the corpora allata (CA) in insects. However, to date, the structure and expression of the gene encoding allatostatins have not been reported in any species other than insects. In this study, we used a combination of a semi-nested polymerase chain reaction (PCR) and screening of a central nervous system cDNA library of Macrobrachium rosenbergii to isolate and sequence a cDNA clone (2885 bp) encoding a 701 amino acid FGLamide allatostatin precursor polypeptide. This is the first reported allatostatin gene in crustacean. The deduced precursor was conceptually split into at least 35 FGLamide allatostatins at dibasic cleavage sites (Lys and Lys/Arg), far more than reported for any other known FGLamide allatostatin precursors from insects (13-14 allatostatins). Reverse transcription-polymerase chain reaction (RT-PCR) analysis demonstrated that the gene was expressed in the brain, gut, thoracic and abdominal ganglia, but not in the heart, muscle, ovary, gill, or hepatopancreas. Furthermore, developmentally-dependent expression of the gene was observed in the brain and thoracic ganglia of the prawn by using semi-quantitative RT-PCR analysis.

Identification of a novel male reproduction-related gene and its regulated expression patterns in the prawn, Macrobrachium rosenbergii.

To identify male-specific genes that could be involved in male development, we screened a subtracted male reproductive tract library and isolated a novel gene named Mar-Mrr (M. rosenbergii male reproduction-related gene). The Mar-Mrr cDNA sequence consists of 683 nucleotides with a 333 nucleotide open reading frame, encoding putative 110 amino acids (11.7473 kDa) precursor protein and a signal peptide consisting of 24 amino acids. Significant developmentally dependent accumulation of the mRNA was observed in the male reproductive tract, specifically in epithelial cells of vas deferens and terminal ampullae.