Immunofluorescence method suitable for large-scale application to malaria.

Norwegian immunological research in gastroenterology is well recognized internationally, and the European Medical Research Council Clinical Network for Gastroenterological Immunology is organized from Oslo. This development can be explained mainly by successful cooperation between clinical gastroenterology and laboratory-based research. A current jubilee in each of these fields may justify this review. It is now well documented that the gut is the largest antibody-producing organ. A unique molecular integration exists between the local B cells and the secretory epithelium to facilitate external transport of dimeric IgA and pentameric IgM. The mucosal immune system is subjected to T-cell regulation and significant local alterations are observed in T- and B-cell populations, and in the macrophage subsets associated with several diseases of the gut. Subsequent functional immune deviation may largely explain mucosal pathology and indicates potential targets for future immunotherapeutic measures. Observations made in the gut mucosa of HIV/AIDS patients have contributed to greater understanding of the complex cellular and molecular interactions involved in mucosal immunity.

Fluorescent Antibody Technique↗

PubMed1995

Photodynamic effects of the cationic porphyrin, mesotetra(4N-methylpyridyl)porphine, on microtubules of HeLa cells.

The treatment of HeLa human carcinoma cells with mesotetra(4N-methylpyridyl)porphine (T4MPyP) and blue light led to damage of the microtubules (MTs). The morphologies of interphase MTs and the mitotic spindle apparatus were analysed by immunofluorescence staining of alpha-tubulin. The extent of MT damage depended on the light dose and the time after photodynamic treatment. After a period of 1 h after irradiation with doses of 0.3 or 1.5 J cm-2 (sublethal conditions, corresponding to survival rates of 90% and 60% respectively), the normal MT network arrangement of interphase cells and the mitotic spindle apparatus of many cells were clearly affected. However, these effects were found to be transient, and several hours after irradiation most MTs resumed control morphology. Higher irradiation doses (4.5 J cm-2, lethal conditions, less than 10% cell survival) resulted in the irreversible alteration of interphase and mitotic MTs. The change in MT organization appeared to be the reason for the observed increase in the mitotic index (MI) after sublethal doses. The largest increase in MI was detected 6 h after treatment (twofold increase over untreated cells) for both sublethal light doses. Most of the cells in mitosis corresponded to metaphase, the number of ana-telophase cells being greatly reduced for the first hours after irradiation with a dose of 1.5 J cm-2. The results, which resemble those observed with inhibitors of MT assembly, suggest that MTs might represent an important target for T4MPyP action.

Fluorescent Antibody Technique↗

PubMed1995

Difference of myosin heavy chain expression between mesangial cells and vascular smooth muscles.

Contraction of the pre- and postglomerular arteries play an important role in the regulation of glomerular blood flow. Mesangial cells may also be involved in the mechanism of this regulation, but it has not been clarified yet whether or not mesangial cells and vascular smooth muscles show an identical phenotype, especially in terms of their contractile proteins. In this study, in order to elucidate any difference in the cellular phenotypes between mesangial cells and renal vascular smooth muscles, we investigated the localization of myosin heavy chain isoforms using a monoclonal antibody against SM1 and SM2. Both SM1 and SM2 are specific to smooth muscles. SM1 is specifically expressed in smooth muscles from early development and SM2 appears after birth. In normal renal tissues, SM1 and SM2 were expressed only in the smooth muscle cells of the arterioles and small arteries. However, glomerular cells, including mesangial cells, were not stained with either anti-SM1 antibody or anti-SM2 antibody. Localization of SM1 and SM-2 was similar to that of alpha-smooth muscle actin (SM alpha-actin). Staining for SM-1 was not observed in the mesangial areas of renal tissues with glomerular disease. These results clearly indicate that mesangial cells have a different phenotype from that of vascular smooth muscle cells in terms of their contractile proteins.

Fluorescent Antibody Technique↗