Involvement of non‑triple helical type VI collagen α1 chain, NTH α1(VI), in the proliferation of cancer cells.

It has been reported that a polypeptide encoded by collagen type VI alpha 1 chain (COL6A1), one of the three α chains of type VI collagen, is strongly associated with the migration and invasion of highly metastatic human pancreatic cancer BxPC‑M8 cells and excessive proliferation of LNCaP cells. We previously reported that non‑triple helical type VI collagen α1 chain, NTH α1(VI), a non‑triple helical polypeptide encoded by COL6A1, is not derived from type VI collagen and exists in cancer cell‑conditioned media. Therefore, NTH α1(VI) may be involved in cancer cell migration, invasion, and proliferation.

Identification of a common epitope in the sequences of COL4A1 and COL6A1 recognized by monoclonal antibody #141.

Identification of a type IV collagen α1 polypeptide in non-triple helical form [NTH α1(IV)], possibly involved in angiogenesis, introduces the further possibility of the existence of non-triple helical forms of other collagen chains. We previously reported that an anti-NTH α1(IV) monoclonal antibody #141 recognizes not only NTH α1(IV) but also a novel non-triple helical collagen polypeptide NTH α1(VI) encoded by COL6A1. In this study, we identified the recognition sequence in order to better understand the properties of antibody #141 and provide clues regarding the biological function of the two non-triple helical molecules.

Cell-based chemical fingerprinting identifies telomeres and lamin A as modifiers of DNA damage response in cancer cells.

Telomere maintenance by telomerase activity supports the infinite growth of cancer cells. MST-312, a synthetic telomerase inhibitor, gradually shortens telomeres at non-acute lethal doses and eventually induces senescence and apoptosis of telomerase-positive cancer cells. Here we report that MST-312 at higher doses works as a dual inhibitor of telomerase and DNA topoisomerase II and exhibits acute anti-proliferative effects on cancer cells and xenografted tumours in vivo.

Type VI collagen α1 chain polypeptide in non-triple helical form is an alternative gene product of COL6A1.

Expression of type IV collagen α1 chain in non-triple helical form, NTH α1(IV), is observed in cultured human cells, human placenta and rabbit tissues. Biological functions of NTH α1(IV) are most likely to be distinct from type IV collagen, since their biochemical characteristics are quite different. To explore the biological functions of NTH α1(IV), we prepared some anti-NTH α1(IV) antibodies.

Preparation and partial characterization of monoclonal antibodies specific for the nascent non-triple helical form of the type IV collagen alpha 1 chain.

This report describes the preparation and partial characterization of monoclonal antibodies that are reactive specifically with the nascently produced non-triple helical form of the type IV collagen α1 chain, designated as NTH α1(IV). These antibodies were nonreactive with the α1 chain of the type IV collagen in the triple-helical conformation. Three antibodies, #141, #179 and #370, with different epitopes in NTH α1(IV) were found to be reactive with the nascent polypeptide secreted from human normal cells and a human carcinoma cell line.

Non-Triple Helical Form of Type IV Collagen α1 Chain.

Type IV collagen with a triple-helical structure composed of three α chains is a major component of basement membrane. Previously, we reported that non-triple helical form of type IV collagen α1 chain (NTHα1(IV)) was isolated from human placenta and the culture media of human cells. In the present study, we report on the localization of NTH α1(IV) with a monoclonal antibody #370, exclusively reactive for the nascent chain, in the rabbit tissues.

Mast cell hyperplasia in the skin of Dsg4-deficient hypotrichosis mice, which are long-living mutants of lupus-prone mice.

Desmosomal cadherins are essential cell adhesion molecules expressed in the epidermis. We identified a mutation of a cadherin superfamily member, namely, desmoglein 4 (Dsg4), in early onset of death (EOD)( hage ) mice with hypotrichosis. The mutation was induced by the insertion of an early transposon II-beta into intron 8 of Dsg4.

Evaluation of the ameliorative effects of immunosuppressants on crescentic glomerulonephritis in SCG/Kj mice.

The therapeutic efficacy of immunosuppressants for treating rapidly progressive glomerulonephritis (RPGN) with crescent formation remains controversial. SCG/Kj mice spontaneously develop RPGN-like symptoms, characteristic of crescentic glomerulonephritis and systemic small vessel vasculitis, associated with the presence of anti-neutrophil cytoplasmic antibodies (ANCA). We evaluated the "ameliorative", not prophylactic, effects of immunosuppressive agents, deoxyspergualin (DSG), cyclophosphamide (CYC) and prednisolone (PDN), on RPGN in these mice.

A novel chemical compound, NK026680, targets dendritic cells to prolong recipient survival after rat liver grafting.

Background: There is great interest in the recently developed immunosuppressant NK026680, which is a derivative of triazolopyrimidine. Its unique chemical structure and action mechanism are completely different from those of conventional immunosuppressants.

Methods: The present study was designed to investigate the effects of NK026680 on rat bone-marrow-derived dendritic cell (BMDC) differentiation and maturation in an in vitro culture system and its applicability in liver transplantation.

Trafficking of QD-conjugated MPO-ANCA in murine systemic vasculitis and glomerulonephritis model mice.

In systemic vasculitis, the serum level of myeloperoxidase (MPO)-specific anti-neutrophil cytoplasmic autoantibodies (MPO-ANCA) is significantly elevated with the progression of disease. We have established a model of murine systemic vasculitis by administration of MPO-ANCA and fungal mannoprotein to C57BL/6 mice. We examined the role of MPO and MPO-ANCA in the pathogenesis of glomerulonephritis and systemic vasculitis in this model using quantum dots (QDs).

NK026680, a novel suppressant of dendritic cell function, prevents the development of rapidly progressive glomerulonephritis and perinuclear antineutrophil cytoplasmic antibody in SCG/Kj mice.

Objective: NK026680 is a newly identified type of immunosuppressive agent that inhibits dendritic cell (DC) functions and consequently reduces the mortality of mice with experimental acute graft-versus-host disease. This study was undertaken to evaluate NK026680 suppression of DC functions in preventing development of rapidly progressive glomerulonephritis (RPGN) and perinuclear antineutrophil cytoplasmic antibodies (pANCA) in SCG/Kj mice.

Methods: Oral administration of NK026680 to SCG/Kj mice began when mice were 8-10 weeks old, before the onset of disease, and continued for 56 days.

Application of Candida solubilized cell wall beta-glucan in antitumor immunotherapy against P815 mastocytoma in mice.

This study was designed to evaluate the antitumor activity of CSBG, purified from the cell wall of Candida albicans IFO1385. First, as an effect of CSBG on P815 mastocytoma, significant prolonged survival and suppression of the tumor growth were observed. Second, the transfer of spleen cells from CSBG-sensitized BALB/c mice to CDF1 mice led to further suppression of tumor growth as well as P815-immunized spleen cells.