The WM-1 successfully and safely disinfected the endoscopes. With running costs of yen 24 per day ($0.21 per day), the WM-1 provides an effective and inexpensive alternative to conventional disinfection equipment.

We investigated the development of lymphoid and non-lymphoid cells in discrete Peyer’s patches (PP) of the pig using immuno-histology and image analysis. In newborn piglets discrete PP were mainly populated by CD2+, CD3+ T cells, and major histocompatibility complex class II+ cells, many of which were of macrophage and dendritic cell lineage. Four days after birth, cells were localized in defined regions: the follicle; the inter-follicular area and the dome region. Compartmentalization within the follicle started about 6 days after birth. The first signs of secondary follicles were seen from about 14 days. The pig discrete PP attained their mature structure at about 3 weeks after birth. Here we show that despite the demonstration at birth of the cell types that support antigen processing and presentation, PP did not fully differentiate morphologically until at least this time when antigen can be handled in an efficient manner.

ABSTRACT. Control of cryptosporidiosis is important in public health. Rivers that are polluted with Cryptosporidium and drinking water that is treated for drinking water production from polluted rivers could result in the waterborne disease of cryptosporidiosis. We carried out an epidemiological study of natural water supplies in Hokkaido, one of the largest dairy prefectures in Japan. To detect Cryptosporidium oocysts in environmental water, the filtration method was used for 28 samples, which were collected from 10 rivers. A method adapted from the United States Environmental Protection Agency (U.S. EPA) filtration method using a cartridge filter has been used for the collection of samples. Oocysts were separated from a pellet by discontinuous sucrose gradient method. Twelve samples were collected from 10 rivers and parasites were purified by iron (III) flocculation method. Cryptosporidium parvum oocysts were identified with the immunofluorescence antibody technique using DIF kit (Cellabs Pty. Ltd., Sydney/Australia). We detected Cryptosporidium oocysts in 6 out of 10 rivers sampled. Fifty percentage (14/28) of the samples were Cryptosporidium-positive. The average number of Cryptosporidium oocysts was 16.73/100 L (max. 80 /100 L).

ABSTRACT. Leukocyte populations present in the discrete Peyer's patches (PP) of the pig were characterized from birth (Day 0) to day 35 after birth by immunohistochemistry and image analysis. Immediately after birth, cell membrane expression of CD2 and CD3, major histocompatibilty complex (MHC) class II (both SLA (swine leukocyte antigen) -DQ + and SLA-DR + ), CD21, 74-22-15 and surface immunoglobulin (sIg) were all demonstrable. Computer assisted morphometric techniques were used to confirm the significant expansion of these cell populations from birth onwards. The distribution of the cell types was not random but suggested a preferential retention of cells at specific sites. This implies a degree of organization of immunological cells within the discrete PP, enhancing the potential to mount immune responses in the most efficient manner. KEY WORDS: discrete Peyer's patch, ontogeny, surface antigen expression, swine.J. Vet. Med. Sci. 63(6): 625-636, 2001 The development of peripheral lymphoid organs has been investigated morphologically by many authors [6, 8,26,29,30]. Most of these studies dealt with the lymphoid cells: B cells, T cells and plasma cells [2,10]. Other reports have been focused on the ontogeny of the non-lymphoid cells in peripheral lymphoid organs: macrophages, interdigitating cells, follicular dendritic cells, and reticulum cells [9,29,30]. Internally, lymphoid organs comprise several compartments [7], each with their own function [13] and characteristic cell population [31]. Within the Peyer's patches (PP), the cooperation between diverse types of lymphoid and nonlymphoid cells is essential for optimal immune response. The aim of this work was to provide information regarding interactions of lymphoid and non-lymphoid cells and to investigate the development of these cells in the pig discrete PP, the major organized lymphoid structures involved in the induction of mucosal immune responses in the intestine. MATERIALS AND METHODSAnimals: Samples were taken from newborn Large White/ Landrace hybrid piglets. All piglets were maintained in conventional conditions on a commercial diet (Willets, Bristol, UK). They ranged from 0-35 days of age and both sexes were used. Piglets were sacrificed at 0 (presuckled), 1, 2, 4, 6, 8, 10, 12, 14, 18, 21, 28 and 35 days after birth. From day 0 to day 12, 3 piglets, 1 from each litter, were used, and from day 14 to day 35, 1 piglet from 1 litter was used. The piglets during this period (day 0-day 35) were not weaned. Tissue collection and preparation: Tissue blocks approximately 5-15 mm × 10 mm, were excised and snap frozen in OCT cryoprotection medium (Tissue-Tek, London, UK) using liquid nitrogen-cooled isopentane. Tissues were labeled for identification by writing on the back of the corkmounting disk. The tissues were wrapped in aluminium foil and polybags to prevent dehydration and stored at -70°C until further processing.Peroxidase anti-peroxidase staining: Serial 4-6 µm frozen sections were cut onto multi-spot, poly-l-lysine precoated slides, dried for 1...

ABSTRACT. A detailed comparison of the accessory cell activities was carried out among murine peritoneal cavity macrophages (PEC-MΦ), peritoneal cavity macrophages stimulated with granulocyte-macrophage colony stimulating factor (GM-CSF) plus interleukin 4 (IL-4), the most popular cytokine combination widely used to generate dendritic cells (DC) and peritoneal cavity macrophage-derived DC (PEC-DC) using a two-way mixed lymphocyte reaction (MLR). All the cell types used efficiently induced statistically significant naïve T cell proliferation at all culture time points and responder:stimulator ratios used. However, marked differences were noted in the magnitude of the proliferative responses. These variations may be attributed to the intensity of expression of MHC class II glycoproteins, as well as the actual numbers of MHC class II + cells. KEY WORDS: mixed lymphocyte reaction, peritoneal cavity macrophage, peritoneal cavity macrophage-derived dendritic cell.