Effects of fermented soymilk with Lacticaseibacillus paracasei YIT 9029 on gut microbiota and defecation habits: a randomised, double-blind, placebo-controlled study

Previous studies have demonstrated that soymilk and Lacticaseibacillus paracasei YIT 9029 (strain Shirota: LcS) each beneficially affect the gut microbiota and defecation habits. To investigate the effects of daily consumption of fermented soymilk containing LcS (FSM), we conducted a randomised, double-blind, placebo-controlled study of 112 healthy Japanese adults with a low faecal Bifidobacterium count. They consumed 100 ml FSM or placebo (unfermented soymilk base) once daily for 4 weeks. Their gut microbiota was analysed by 16S rRNA gene amplicon sequencing and quantitative reverse transcription-polymerase chain reaction (PCR), and faecal short-chain fatty acids (SCFAs) and urinary putrefactive products were assessed during the pre- and post-consumption periods. Defecation habits were examined weekly using a subjective questionnaire. In the post-consumption period, living LcS were not detected in two subjects in the FSM group (n = 57) but were detected in one subject in the SM group (n = 55). The FSM group had a significantly higher number and relative abundance of faecal lactobacilli compared with the placebo group. The relative abundance of Bifidobacterium, alpha-diversity of microbiota, and concentrations of acetate and total SCFAs in faeces were significantly increased in the FSM group, although no significant differences were detected between the groups. The number of defecations and defecation days per week significantly increased in both groups. Subgroup analysis of 109 subjects, excluding 3 with inconsistent LcS detection (2 and 1 subjects in the FSM and SM groups, respectively), revealed that the FSM group (n = 55) had significantly greater increases in faecal acetate concentration compared with the SM group (n = 54) and significant upregulation of pathways related to energy production or glucose metabolism in the gut microbiota. These findings suggest that daily FSM consumption improves the gut microbiota and intestinal environment in healthy adults and may help to maintain health and prevent diseases. Registered at the University Hospital Medical Information Network (UMIN) clinical trials registry under: UMIN 000035612.

Peripheral neuropathy in the pre-diabetic state of the type 2 diabetes mouse model (TSOD mice) involves TRPV1 expression in dorsal root ganglions

Peripheral neuropathy, which is a complication of diabetes mellitus (DM), is thought to occur in the pre-DM state, being known as impaired glucose tolerance (IGT) neuropathy, although its pathogenesis is unknown. Since it is reversible, an effective treatment at the pre-DM stage could stop the progression of peripheral neuropathy and improve patients’ quality of life and reduce medical costs. We investigated the hypersensitivity to mechanical and thermal stimuli during the pre-DM state in Tsumura Suzuki Obese Diabetes (TSOD) mice, a type 2 DM mouse model. The expression pattern of the Transient Receptor Potential Vanilloid 1 (TRPV1)-positive cells in the dorsal root ganglia (DRG) was examined in TSOD mice, which showed a pre-DM state at 5–12 weeks of age and decreased mechanical and thermal nociceptive thresholds. Additionally, the size of TRPV1-positive cells in TSOD mice increased compared with that in non-diabetic controls (Tsumura Suzuki Non-Obesity; TSNO). Furthermore, the expression of TRPV1 on myelinated nerve fibers (neurofilament heavy-positive cells) had significantly increased. Thus, TSOD mice in the pre-DM state at 5–12 weeks of age could be a useful animal model of IGT neuropathy. We also hypothesized that the development of IGT neuropathy may involve a switch in TRPV1 expression from small, unmyelinated neurons to large, myelinated neurons in the DRG.

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The mechanism of peripheral neuropathy was investigated in insulin resistance state.

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Tsumura Suzuki Obese Diabetes (TSOD) mice showed a pre-diabetic state.

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TSOD mice showed mechanical and thermal hypersensitivity in a pre-diabetic state.

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The TRPV1 expression shifted to larger dorsal root ganglia (DRG) cells in TSOD mice.

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TRPV1 expression in myelinated neurons of the DRG was involved in neuropathy.

Plasmodium falciparum RIFIN is a novel ligand for inhibitory immune receptor LILRB2

Plasmodium falciparum causes the most severe form of malaria. Acquired immunity against P. falciparum provides insufficient protection even after repeated infections. Therefore, P. falciparum parasites might exploit inhibitory receptors for immune evasion. P. falciparum RIFINs are products of a multigene family consisting of 150-200 genes. Previously, we demonstrated that some RIFINs downregulate the immune response through the leukocyte immunoglobulin-like receptor (LILR) family inhibitory receptor, LILRB1, and leukocyte-associated immunoglobulin-like receptor 1, LAIR1. In this study, we further analyzed the expression of inhibitory receptor ligands on P. falciparum-infected erythrocytes and found that P. falciparum-infected erythrocytes expressed ligands for another LILR family inhibitory receptor, LILRB2, that recognizes HLA class I molecules as a host ligand. Furthermore, we identified that a specific RIFIN was a ligand for LILRB2 by using a newly developed RIFIN expression library. In addition, the domain 3 of LILRB2 was involved in RIFIN binding, whereas the domains 1 and 2 of LILRB2 were involved in the binding to HLA class I molecules. These results suggest that inhibitory receptor LILRB2 is also targeted by RIFIN for immune evasion of P. falciparum similar to LILRB1 and LAIR1.

Effects of fermented soymilk with Lactobacillus casei Shirota on skin condition and the gut microbiota: a randomised clinical pilot trial

Several clinical studies have shown that isoflavones and Lactobacillus casei Shirota (LcS) have beneficial effects on skin condition and the gut microbiota, respectively. Thus, we investigated the effects of consecutive intake of fermented soymilk (FSM) with LcS on skin condition and the gut microbiota, as well as isoflavone bioavailability, in a randomised, double-blind, placebo-controlled trial as a pilot study. Sixty healthy premenopausal Japanese women received FSM containing a moderate level of isoflavone aglycones and a probiotic LcS, or soymilk (SM) containing neither of them, twice a day for 8 weeks. Skin condition was assessed by a subjective questionnaire for face and morphological analysis of the stratum corneum on the inner forearm. Faecal microbiota and urinary isoflavone were analysed by 16S rRNA gene amplicon sequencing and high-performance liquid chromatography tandem mass spectrometry, respectively. Both the FSM and SM groups had improved skin condition as assessed from scores of overall satisfaction, dryness, moisture, elasticity, coarseness, pigmentation and/or stratum corneum morphology, as well as significantly increased levels of urinary isoflavones during the intake period compared with the pre-intake period, although there were no significant differences between the two groups. There was a significant positive correlation between urinary isoflavone levels and skin questionnaire scores. In contrast, the relative abundance levels of Lactobacillaceae significantly increased and those of Bifidobacteriaceae tended to increase during the intake period compared with the pre-intake period. For the after-intake period they only decreased significantly in the FSM group. The levels of Enterobacteriaceae and Porphyromonadaceae significantly decreased during the intake period in the FSM group. These findings suggest that daily intake of FSM, as well as SM, provides health benefits that improve skin condition via increased levels of isoflavone absorption in the body, and that only FSM beneficially modifies the gut microbiota in premenopausal healthy women.

Corrigendum: Immune evasion of Plasmodium falciparum by RIFIN via inhibitory receptors

This corrects the article DOI: 10.1038/nature24994.

Immune evasion of Plasmodium falciparum by RIFIN via inhibitory receptors

Malaria is among the most serious infectious diseases affecting humans, accounting for approximately half a million deaths annually¹. Plasmodium falciparum is the causative agent of most life-threatening malaria cases. Acquired immunity to malaria is inefficient, even after repeated exposures to P. falciparum²; immune regulatory mechanisms employed by P. falciparum remain largely unclear. Here, we show that P. falciparum uses immune inhibitory receptors for immune evasion. RIFINs, products of a polymorphic multigene family comprising approximately 150–200 genes per parasite genome³, are expressed on the surface of infected erythrocytes. We found that a subset of RIFINs binds to either leucocyte immunoglobulin-like receptor B1 (LILRB1) or leucocyte-associated immunoglobulin-like receptor 1 (LAIR1). LILRB1-binding RIFINs inhibited activation of LILRB1-expressing B cells and NK cells. Furthermore, interactions between LILRB1 and P. falciparum-infected erythrocytes isolated from malaria patients were associated with severe malaria, although an extended study with larger sample sizes is required to confirm the findings. These results suggest that P. falciparum has acquired multiple RIFINs to evade the host immune system by targeting immune inhibitory receptors.

[Current Situation Survey of the Measures to Prevent Medication Errors in the Operating Room: Report of the Japan Society of Anesthesiologists Safety Commission Working Group for Consideration of Recommendations for Color Coding of Prepared Syringe Labels for Prevention of Medication Errors]

BACKGROUND

In the case of medication errors which are among the more frequent adverse events that occur in the hospital, there is a need for effective measures to prevent incidence. According to the Japan Society of Anesthesiologists study "Drug incident investigation 2005-2007 years", "Error of a syringe at the selection stage" was the most frequent (44.2%). The status of current measures and best practices implemented in Japanese hospitals was the focus of a subsequent investigation.

METHODS

Representative specialists in anesthesiology certified hospitals across the country were surveyed via a questionnaire sampling that lasted 46 days. Investigation method was via the Web with survey responses anonymous.

RESULTS

With respect to preventive measures implemented to mitigate risk of medication errors in perioperative settings, responses included: incident and accident report (215 facilities, 70.3%), use of pre-filled syringes (180 facilities, 58.8%), devised the arrangement of dangerous drugs (154 facilities, 50.3%), use of the product with improper connection preventing mechanism (123 facilities, 40.2%), double-check (116 facilities, 37.9%), use of color barreled syringe (115 facilities, 37.6%), use of color label or color tape (89 facilities, 29.1%), presentation of medication such as placing the ampoule or syringe on a tray by dividing color code for drug class on a tray (54 facilities, 17.6%), the discontinuance of handwritten labels (23 facilities, 7.5%), use of a drug verification system that uses bar code (20 facilities, 6.5%), and facilities that have not implemented any means (11 facilities, 3.6%), others not mentioned (10 facilities, 3.3%), and use of carts that count/account the agents by drug type and record selection and number picked automatically (6 facilities, 2.0%). Drug name identification affixed to the syringe via perforated label torn from the ampoule/vial, etc. (245 facilities, 28.1%), handwriting directly to the syringe (208 facilities, 23.8%), use of the attached label (like that comes with the product) (187 facilities, 21.4%), handwriting on the plain tape (87 facilities, 10.0%), printing labels (62 facilities, 7.1%), printed color labels (44 facilities, 5.0%), handwriting on the color tape (27 facilities, 3.1%), machinery for printing the drug name by scanning bar code of the ampoule, etc.(10 facilities, 1.1%), others (3 facilities, 0.3%), no description on the prepared drug (0 facilities, 0%). The awareness of international standard color code, such as by the International Organization for Standardization (ISO), was only 18.6%.

CONCLUSIONS

Targeting anesthesiology certified hospitals recognized by the Japan Society of Anesthesiologists, the result of the survey on the measures to prevent medication errors during perioperative procedures indicated that various measures were documented in use. However, many facilities still use hand written labels (a common cause for errors). Confirmation of the need for improved drug name and drug recognition on syringe was documented.

Monocyte infiltration into obese and fibrilized tissues is regulated by PILRα

Paired immunoglobulin-like type 2 receptor α (PILRα) is an inhibitory receptor that is mainly expressed on myeloid cells, and negatively regulates neutrophil infiltration during inflammation. However, PILRα role on monocyte has not been described. Under both steady-state and inflammatory conditions, monocytes migrate into tissues and differentiate into macrophages. Macrophages in adipose and liver tissues play important roles in tissue homeostasis and pathogenesis of metabolic diseases. Here, we found that PILRα controls monocyte mobility through regulating integrin signaling and inhibiting CD99-CD99 binding. Moreover, we found that Pilra(-/-) mice developed obesity and hepatomegaly with fibrosis, and the numbers of macrophages in adipose and liver tissues are significantly increased in Pilra(-/-) mice. These data suggest that immune inhibitory receptor, PILRα, plays an important role in the prevention of obesity and liver fibrosis.

Total skin electron beam therapy using an inclinable couch on motorized table and a compensating filter

Total skin electron beam is a specialized technique that involves irradiating the entire skin from the skin surface to only a few millimetres in depth. In the Stanford technique, the patient is in a standing position and six different directional positions are used during treatment. Our technique uses large electron beams in six directions with an inclinable couch on motorized table and a compensating filter was also used to spread the electron beam and move its intensity peak. Dose uniformity measurements were performed using Gafchromic films which indicated that the surface dose was 2.04 ± 0.05 Gy. This technique can ensure the dose reproducibility because the patient is fixed in place using an inclinable couch on a motorized table.

Transport of misfolded endoplasmic reticulum proteins to the cell surface by MHC class II molecules

Nascent MHC class II molecules are associated with the invariant chain and are transported to the endolysosomal pathway, where MHC class II molecules acquire peptide antigens. On the other hand, misfolded endoplasmic reticulum (ER) proteins are generally degraded in the cells and are neither expressed on the cell surface nor secreted. Here, we found that MHC class II molecules associate with some misfolded ER proteins via the peptide-binding groove in competition with invariant chain. The misfolded proteins associated with MHC class II molecules are transported intact to the cell surface without processing to peptides. Furthermore, these complexes efficiently stimulate antigen-specific B cells. These findings reveal that MHC class II molecules function as a chaperone for the cell surface expression of misfolded ER proteins. In addition, we suggest that MHC class II molecules present not only peptides but also intact host-cell-derived proteins on the cell surface. These findings provide new insights into the function of MHC class II molecules.

Biological effects of probiotics: what impact does Lactobacillus casei shirota have on us?

Probiotics have been defined as live bacteria beneficial to the host when administered in adequate amounts. To evaluate the effect of probiotics on the prevention of carcinogenesis, Lactobacillus casei Shirota (LcS) was given to the patients who had undergone the resection of superficial bladder cancer, and administration of LcS significantly reduced the recurrence rate of bladder cancer. When LcS was given to the patients whose colonic polyps were surgically removed, the recurrence of colorectal cancer with moderate or severe atypia was suppressed. To assess the putative actions of LcS on innate immune responses, we examined the effect of LcS on natural killer (NK) cell activity in humans. Daily ingestion of fermented milk containing LcS restored NK cell activity in healthy subjects with low NK cell activity as well as human T lymphotropic virus (HTLV)-1-associated myelopathy patients. When peripheral blood mononuclear cells from healthy humans were cultured in the presence of heat-killed LcS, NK cell activity was augmented, which were partly mediated by monocyte-derived interleukin (IL)-12. These findings suggest that LcS may help the reinforcement of our defense system against cancer by modulating innate immune functions.

Involvement of ST6Gal I in the biosynthesis of a unique human colon cancer biomarker candidate, alpha2,6-sialylated blood group type 2H (ST2H) antigen

The alpha2,6-sialylated blood group type 2H (ST2H) antigen (Fucalpha1-2(NeuAcalpha2-6)Galbeta1-4GlcNAcbeta1-3Galbeta1-4Glc-Cer) is a fucoganglioside found in human colon cancer tissues. To elucidate an enzyme responsible for the ST2H antigen formation, we screened some partially purified candidate enzymes, alpha2,6-sialyltransferases, ST6Gal I and ST6Gal II, and alpha1,2-fucosyltransferases, FUT1 and FUT2 for their activities towards pyridylaminated type 2H (Fucalpha1-2Galbeta1-4GlcNAcbeta1-3Galbeta1-4Glc-PA) or LS-tetrasaccharide c (LST-c: NeuAcalpha2-6Galbeta1-4GlcNAcbeta1-3Galbeta1-4Glc-PA) as acceptor substrates. Here we show the ST6Gal I transfers NeuAc from the donor CMP-NeuAc to the terminal Gal of PA-type 2H, which formed the ST2H antigen, but the others could not synthesize it. Using a recombinant ST6Gal I, enzymatic reactions with two types of acceptors, PA-type 2H and PA-lacto-N-neotetraose (LNnT), were kinetically analysed. On the basis of catalytic efficiency (V(max)/K(m)), the specificity of ST6Gal I towards the PA-type 2H was estimated to be 42 times lower than that for PA-LNnT. The overexpression of ST6Gal I in human colon cancer DLD-1 cells effectively resulted in the ST2H antigen formation, as judged by LC-ESI-IT-MS. Many lines of evidence suggest the up-regulation of ST6Gal I in human colon cancer specimens. Collectively, these findings indicate that ST6Gal I is responsible for ST2H antigen biosynthesis in human colon cancer cells.

Novel ganglioside found in adenocarcinoma cells of Lewis-negative patients

We have precisely analyzed the structures of glycosphingolipids of human cancer cells and normal epithelial cells using several methods, including enzymatic release of carbohydrate moieties, fluorescent labeling, and identification using 2D mapping, enzymatic digestion, and mass spectrometry. These analyses enabled the identification of novel tumor-associated carbohydrate antigens that can be used to elucidate the involvement of carbohydrates in cancer malignancy and could act as candidate tumor markers. In our previous study, we identified a novel glycosphingolipid that accumulates in colon cancer cells, NeuAcα2-6(Fucα1-2)Galβ1-4GlcNAcβ1-3Galβ1-4Glc (α2-6 sialylated type 2H, ST2H). Here, structural analyses of cancer cells and normal epithelial cells from 60 colorectal and five pancreatic cancer patients, including four and two Lewis-negative individuals, respectively, reveal the presence of an additional novel glycosphingolipid, NeuAcα2-6(Fucα1-2)Galβ1-3GlcNAcβ1-3Galβ1-4Glc (α2-6 sialylated type 1H, ST1H). ST2H was found in colorectal and pancreatic cancer cells from about half of the cases. Unlike ST2H, ST1H was found in cancer cells from three out of six Lewis-negative patients (i.e., two cases of colorectal and one case of pancreatic cancer). However, the moiety was not found in normal epithelial cells or cancer cells from 59 Lewis-positive patients. These findings suggest that the accumulation of this carbohydrate antigen occurs predominantly in cancer cells of Lewis-negative patients. When the ST1H epitope is also carried on mucins as well as glycosphingolipids, this epitope is a promising tumor marker candidate, especially for Lewis-negative individuals.

Unusual accumulation of sulfated glycosphingolipids in colon cancer cells

The structures of glycosphingolipids from highly purified colorectal cancer cells and normal colorectal epithelial cells of 16 patients have been analyzed in fine detail (Misonou Y, Shida K, Korekane H, Seki Y, Noura S, Ohue M, Miyamoto Y. 2009. Comprehensive Clinico-Glycomic Study of 16 Colorectal Cancer Specimens: Elucidation of aberrant glycosylation and ts mechanistic causes in colorectal cancer cells. J Proteome Res. 8:2990-3005). Further structural analyses demonstrated that colon cancer cells from two patients accumulated unusual glycosphingolipids which were not observed in either colorectal cancer cells or normal colorectal epithelial cells from the other patients. Mass spectrometry analyses revealed that the unusual structures include sulfated oligosaccharides. The structures of the glycosphingolipids of the cancer cells from these two cases were analyzed by methods which include enzymatic release of carbohydrate moieties, fluorescent labeling with aminopyridine and identification using two-dimensional mapping, enzymatic digestion and mass spectrometry together with methanolysis, and the use of newly synthesized sulfo-fucosylated oligosaccharides as standards. The colon cancer cells from one of the patients demonstrate a variety of oligosaccharides as major components which are sulfated at the C6 position of subterminal GlcNAc and at C3 positions of terminal galactose with or without sialylation or fucosylation. These include 6-sulfo Le(x), 6'-sialyl 6-sulfo lactosamine, and 3'-sialyl 6-sulfo Le(x), in addition to sialylated or fucosylated derivatives of type-1 and type-2 hybrid oligosaccharides. The colon cancer cells from the other patient have two kinds of sulfated oligosaccharides, a 6-sulfo Le(x) structure and a 3'-sulfo Le(x) structure, as minor components. Taking into consideration the clinical features of the two patients, the biological significance of sulfated glycosphingolipids on cancer cells is discussed.

The cell death machinery controlled by Bax and Bcl-XL is evolutionarily conserved in Ciona intestinalis

Bax and Bcl-XL are key regulators of apoptosis in mammals. Here we report the functional characterization of two Bcl-2 homologues, ciBax and ciBcl-XL, in a basal invertebrate-chordate ascidian Ciona intestinalis. CiBax is a Ciona homologue of the BH1-3 pro-apoptotic protein Bax, whereas ciBcl-XL is a Bcl-XL-like anti-apoptotic protein. Molecular modeling analysis showed that ciBax and ciBcl-XL share both sequence and structural similarities to human Bax and Bcl-XL, respectively. Like their human counterparts, ciBax could form a homodimer or oligomers as well as heterodimerize with ciBcl-XL, and overexpression of ciBax caused apoptosis that could be attenuated by ciBcl-XL. Mutagenesis studies showed that the BH3 domain of ciBax is critical for its cell death-inducing function and also for its interaction with ciBcl-XL. In Ciona embryos, ectopic expression of ciBax but not its BH3 deletion mutant resulted in cell dissociation and apoptosis after late gastrula stage of embryonic development. Moreover, not only wild type ciBcl-XL but also a mutant ciBcl-XL(F101V), which is unable to interact with ciBax, could block cell dissociation and developmental deficit in Ciona embryos induced by overexpression of ciBax. Taken together, these findings suggest that functional homologues of both the BH1-3 death effector Bax and the pro-survival Bcl-XL exist in sea squirt Ciona intestinalis, and they control the cell death machinery independent of their heterodimerization.

Combinational recognition of bacterial lipoproteins and peptidoglycan by chicken Toll-like receptor 2 subfamily

Human Toll-like receptor 2 (TLR2) subfamily recognizes bacterial lipoproteins (BLP) and peptidoglycan (PGN). According to the genome information, chicken has structural orthologs of TLRs1 and 2, in addition to TLRs3, 4, 5 and 7. Chicken has two additional TLRs, TLR15 and TLR21, whose orthologs human lacks. The chicken (ch)TLR1 and 2 genes are individually duplicated to encode for four different proteins, chTLR1-1, 1-2, 2-1 and 2-2, of the TLR2 subfamily. Here we investigated the functional profile of these TLR2 subfamily proteins of chicken. By NF-kappaB reporter assay using HEK293 cells, we found that chTLR2-1 and chTLR1-2 cooperatively signal the presence of PGN. A combination of chTLR2-1 and chTLR1-2 also most efficiently recognized diacylated BLP, macrophage-activating lipopeptide 2kDa (Malp-2), while the combination of chTLR2-1 and chTLR1-1 failed to recognize Malp-2. All combinations, however, recognized triacylated BLP, Pam3. Consistent with these results, human TLR2-stimulating mycobacteria preparations, BCG-cell wall and cell lysate of Mycobacterium avium, induced activation of NF-kappaB in cells expressing chTLR2-1 and 1-2 and to lesser extents, cells with chTLR2-2 and either of chTLR1. Strikingly, expression of either of these alone did not activate the reporter for NF-kappaB. These chTLRs are likely to have the combination functional feature as in the human TLR2 subfamily. Confocal and immunoprecipitation analyses of human cell transfectants showed that they cluster on the cell surface by a physical molecular association, causing all of them to merge and coprecipitate. These results suggest that chTLR2 subfamily members discriminate between their ligands by combinational events.

Lamprey TLRs with properties distinct from those of the variable lymphocyte receptors

Fish express mammalian-type (M-type) TLRs consisting of leucine-rich repeats (LRRs) and Toll-IL-1R (TIR) homology domain for immunity, whereas invertebrates in deuterostomes appear to have no orthologs of M-type TLRs. Lampetra japonica (lamprey) belongs to the lowest class of vertebrates with little information about its TLRs. We have identified two cDNA sequences of putative TLRs in the lamprey (laTLRs) that contain LRRs and TIR domains. The two laTLRs were 56% homologous to each other, and their TIRs were similar to those of members of the human TLR2 subfamily, most likely orthologs of fish TLR14. We named them laTLR14a and laTLR14b. We raised a rabbit polyclonal Ab against laTLR14b and identified a 85-kDa protein in a human HEK293 transfectant by immunoblotting using the Ab. FACS, histochemical, and confocal analyses showed that laTLR14b is expressed intracellularly in lamprey gill cells and that the overexpressed protein resides in the endoplasmic reticulum of human and fish (medaka) cell lines. Because natural agonists of TLR14 remained unidentified, we made a chimera construct of extracellular CD4 and the cytoplasmic domain of laTLR14. The chimera molecule of laTLR14b, when expressed in HEK293 cells, elicited activation of NF-kappaB and, consequently, weak activation of the IFN-beta promoter. laTLR14b mRNA was observed in various organs and leukocytes. This lamprey species expressed a variable lymphocyte receptor structurally independent of laTLR14 in leukocytes. Thus, the jawless vertebrate lamprey possesses two LRR-based recognition systems, the variable lymphocyte receptor and TLR, and the M-type TLRs are conserved across humans, fish, and lampreys.

Evaluation of laser microdissection as a tool in cancer glycomic studies

Laser microdissection (LMD) is a recent development that enables the isolation of specific cell populations from tissue sections. This study focuses on the potential of LMD as a tool in cancer glycomics using colon cancer as a model. LMD was performed on hematoxylin and eosin stained frozen tissue sections. Tumor cells and normal epithelial cells were selectively microdissected. N-Glycans from the LMD- and the bulk tissue-derived samples were liberated by hydrazinolysis and then labeled with 2-aminopyridine. After sialidase digestion, the resulting asialo-N-glycans were analyzed by normal and reversed phase HPLC combined with mass spectrometry. Comparison of the various N-glycan profiles with the aid of LMD identified seven characteristic N-glycans with significantly different expression profiles between normal and cancerous cells that could not be detected by conventional analysis. Thus, LMD is a potent and useful tool for analyzing variations in the expression of N-glycans by overcoming the problem of tissue sample heterogeneity.

Interleukin-12 is involved in the enhancement of human natural killer cell activity by Lactobacillus casei Shirota

We conducted a placebo-controlled, cross-over trial to examine the effect of Lactobacillus casei Shirota (LcS) on natural killer (NK) cell activity in humans. NK cell activity exhibited a declining trend during the period of placebo ingestion, but NK cell activity increased after intake for 3 weeks of fermented milk containing 4 x 10(10) live LcS. When human peripheral blood mononuclear cells were cultured in the presence of heat-killed LcS, NK cell activity was enhanced. The ability of LcS to enhance NK cell activity and induce interleukin (IL)-12 production was correlated, and the addition of anti-IL-12 monoclonal antibody reduced the enhancement of NK cell activity triggered by LcS. In addition, separation of NK cells from LcS-stimulated monocytes with membrane filter reduced NK cell activity to the intermediate level and almost deprived monocytes of the ability to produce IL-12. These results demonstrate that LcS can enhance NK cell activity in vivo and in vitro in humans, and IL-12 may be responsible for enhancement of NK cell activity triggered by LcS.

Induction of Interleukin-12 by Lactobacillus Strains Having a Rigid Cell Wall Resistant to Intracellular Digestion

Some strains of lactobacilli can stimulate macrophages and dendritic cells to secrete IL-12, which plays a key role in activating innate immunity. We examined the IL-12-inducing ability of 47 Lactobacillus strains belonging to 10 species in mouse peritoneal macrophages, and characterized the properties important for the induction of IL-12. Although considerable differences in IL-12-inducing ability were observed among the strains tested, almost all strains belonging to the Lactobacillus casei group (L. casei, Lactobacillus rhamnosus, and Lactobacillus zeae) or to Lactobacillus fermentum induced high levels of IL-12. Phagocytosis of lactobacilli was necessary for IL-12 induction, and the strains with strong IL-12 induction were relatively resistant to lysis in the macrophages. The sensitivity of Lactobacillus strains to in vitro treatment with M-1 enzyme, a member of the N-acetylmuramidases, was negatively correlated with IL-12-inducing ability. Using a probiotic strain, L. casei strain Shirota (LcS), we showed that the cell wall of LcS could be digested by long-term treatment with a high dose of M-1 enzyme and that the IL-12-inducing ability was diminished according to the duration of the enzyme treatment. The soluble polysaccharide-peptidoglycan complex released from the cell wall of LcS did not induce IL-12, whereas the insoluble intact cell wall of LcS induced IL-12. These results suggest that the intact cell wall structure of lactobacilli is an important element in the ability to induce IL-12 and that Lactobacillus strains having a rigid cell wall resistant to intracellular digestion effectively stimulate macrophages to induce IL-12.

Regulator of complement activation (RCA) locus in chicken: identification of chicken RCA gene cluster and functional RCA proteins

A 150-kb DNA fragment, which contains the gene of the chicken complement regulatory protein CREM (formerly named Cremp), was isolated from a microchromosome by screening bacterial artificial chromosome library. Within 100 kb of the cloned region, three complete genes encoding short consensus repeats (SCRs, motifs with tandemly arranged 60 aa) were identified by exon-trap method and 3'- or 5'-RACE. A chicken orthologue of the human gene 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 2, which exists in close proximity to the regulator of complement activation genes in humans and mice, was located near this chicken SCR gene cluster. Moreover, additional genes encoding SCR proteins appeared to be present in this region. Three distinct transcripts were detected in RNA samples from a variety of chicken organs and cell lines. Two novel genes named complement regulatory secretory protein of chicken (CRES) and complement regulatory GPI-anchored protein of chicken (CREG) besides CREM were identified by cloning corresponding cDNA. Based on the predicted primary structures and properties of the expressed molecules, CRES is a secretory protein, whereas CREG is a GPI-anchored membrane protein. CREG and CREM were protected host cells from chicken complement-mediated cytolysis. Likewise, a membrane-bound form of CRES, which was artificially generated, also protected host cells from chicken complement. Taken together, the chicken possesses an regulator of complement activation locus similar to those of the mammals, and the gene products function as complement regulators.

TIR-containing adapter molecule (TICAM)-2, a bridging adapter recruiting to toll-like receptor 4 TICAM-1 that induces interferon-beta

Lipopolysaccharide (LPS) is an agonist for Toll-like receptor (TLR) 4 and expresses many genes including NF-kappaB- and interferon regulatory factor (IRF)-3/IFN-inducible genes in macrophages and dendritic cells (DCs). TICAM-1/TRIF was identified as an adapter that facilitates activation of IRF-3 followed by expression of interferon (IFN)-beta genes in TLR3 signaling, but TICAM-1 does not directly bind TLR4. Although MyD88 and Mal/TIRAP adapters functions downstream of TLR4, DC maturation and IFN-beta induction are independent of MyD88 and Mal/TIRAP. In this investigation, we report the identification of a novel adapter, TICAM-2, that physically bridges TLR4 and TICAM-1 and functionally transmits LPS-TLR4 signaling to TICAM-1, which in turn activates IRF-3. In its structural features, TICAM-2 resembled Mal/TIRAP, an adapter that links TLR2/4 and MyD88. However, TICAM-2 per se exhibited minimal ability to activate NF-kappaB and the IFN-beta promoter. Hence, in LPS signaling TLR4 recruits two types of adapters, TIRAP and TICAM-2, to its cytoplasmic domain that are indirectly connected to two effective adapters, MyD88 and TICAM-1, respectively. We conclude that for LPS-TLR4-mediated activation of IFN-beta, the adapter complex of TICAM-2 and TICAM-1 plays a crucial role. This results in the construction of MyD88-dependent and -independent pathways separately downstream of the two distinct adapters.

Prediction of the prototype of the human Toll-like receptor gene family from the pufferfish, Fugu rubripes, genome

The insect Toll family of proteins and their mammalian counterparts seemingly shared one common ancestor and evolved independently. Here we demonstrated that the prototype of the mammalian-type (M-type) Toll family is shared by the fish and humans. According to the draft of the pufferfish Fugu genome project, the signature Toll-IL-1 receptor homology domain (TIR domain) has been conserved during evolution. FuguTLR2, 3, 5, 7, 8 and 9 members correspond structurally to respective mammalian TLRs. One Fugu TLR showed equally high amino acid identity to human TLR1, 6 and 10, and we named it FuguTLR1. Fugu rubripes has genes for TLR21 and 22, which are unique to fish. One possible interpretation of these findings is that TLR1, 2, 3, 4, 5, 7, 8, 9, 21 and 22 existed in the ancestral genome common to fish and mammals, and that TLR4 was lost in the fish lineage, while TLR21 and 22 were lost in the mammalian lineage. Strikingly, a solitary ascidian, Halocynthia roretzi, has only a few Toll-like proteins, which, like Caenorhabditis elegans Toll, represent primitive ones before the expansion of the Toll family. Therefore, the expansion of TLR genes should have occurred earlier than fish, but not C. intestinalis, separated evolutionarily from mammals. These results infer that the appearance of the M-type innate system was completed before or concomitant with the appearance of acquired immunity. We interpret the present data to mean that the differences of TLRs identified in this study between fishes and humans may be rather peripheral, partially due to selection pressure exerted by pathogens in distinct environments.

Lactobacillus casei strain Shirota suppresses serum immunoglobulin E and immunoglobulin G1 responses and systemic anaphylaxis in a food allergy model

BACKGROUND

Our previous study using allergen-sensitized murine splenocyte cultures has shown that Lactobacillus casei strain Shirota (LcS), a lactic acid bacterium widely used as a starter for fermented milk products, suppresses IgE production through promoting a dominant Th1-type response mediated by IL-12 induction.

OBJECTIVE

We tried to evaluate the ability of LcS to suppress both IgE response and allergic reactions in vivo using a food allergy model with ovalbumin-specific T cell receptor transgenic (OVA-TCR-Tg) mice.

METHODS

The ability of heat-killed LcS to induce IL-12 in serum was tested. OVA-TCR-Tg mice were fed a diet containing OVA for 4 weeks and injected with LcS intraperitoneally three times in the first week of this period. Cytokine and antibody secretion by splenocytes, and serum IgE and IgG1 responses were examined. The inhibitory effect of LcS on systemic anaphylaxis induced by intravenous challenge of OVA-fed OVA-TCR-Tg mice with OVA was also tested.

RESULTS

Intraperitoneal injection of LcS induced an IL-12 response in the serum of OVA-TCR-Tg mice. In the food allergy model, LcS administration skewed the pattern of cytokine production by splenocytes toward Th1 dominance, and suppressed IgE and IgG1 secretion by splenocytes. The ability of LcS to modulate cytokine production was blocked by anti-IL-12 antibody treatment. LcS also inhibited serum OVA-specific IgE and IgG1 responses and diminished systemic anaphylaxis.

CONCLUSION

LcS administration suppresses IgE and IgG1 responses and systemic allergic reactions in a food allergy model, suggesting a possible use of this lactic acid bacterium in preventing food allergy.

High levels of RAE-1 isoforms on mouse tumor cell lines assessed by anti-"pan" RAE-1 antibody confer tumor susceptibility to NK cells

Two sublines of the benzpyrene-induced mouse hepatoma cell line, G-1 and G-5, showed low and high metastatic ability, respectively, to the lung. We produced a polyclonal antibody (pAb) against RAE-1alpha. Five isoforms of RAE-1 have been identified to date, and this pAb recognized all isoforms and was named anti-"pan" RAE-1 pAb. The level of RAE-1 was approximately 5-fold higher in G-5 than in G-1, which was almost RAE-1-negative, as determined using anti-pan RAE-1 pAb. Expression levels of other markers including MHC class I (MHC-I) and Qa-1b were very low and indistinguishable in these sublines. NK-mediated cytotoxicity was determined with these sublines; G-5 was highly susceptible to NK-mediated cytolysis, while G-1 was relatively resistant. The NK-mediated G-5 > G-1 killing profile was diminished if the G-5 cells were pretreated with F(ab)(2)(') of anti-pan RAE-1 pAb. G-1, when transfected with Rae-1alpha cDNA, acquired NK-responsiveness similar to that of G-5. These and additional data using mouse cell lines with low MHC-I levels and various RAE-1 levels also demonstrated that RAE-1 level is critically associated with NK-susceptibility in tumor cells.

High serum levels of additional IL-18 forms may be reciprocally correlated with IgE levels in patients with atopic dermatitis

We established an ELISA system for determination of as yet unidentified species of interleukin 18 (IL-18), named IL-18 type 2, in human serum. Serum IL-18 levels and their effect on IgE levels were examined in 18 patients with atopic dermatitis (AD) with no other allergic symptoms. Three of these patients showed high IL-18 type 2 concentrations (25-100 ng/ml) in their blood serum, and this IL-18 type 2 was detectable only with our established ELISA system. In contrast, the level of the conventional form of IL-18 (type 1) was found to be 50-400 pg/ml in all patients by the commercially available ELISA. The levels of type 1 IL-18 showed no correlation with those of type 2 and approximately 2-fold higher in AD patients than in normal subjects. IL-12 p40 and IgE levels were correlated in the patients with no IL-18 type 2, and interestingly, relatively low IgE concentrations were detected in the three IL-18 type 2-positive patients. They showed considerable levels of IL-12 p40 unlike normal subjects. The IFNgamma-inducing activity of IL-18 type 2 was >100-fold less potent by weight ratio than that of a recombinant 'active' IL-18 preparation, even after the treatment with Caspase 1. Although the relationship between AD and serum IgE levels is not clear cut, IL-18 type 2 appears to play some roles in the Th2-polarization involving IgE production in association with immune responses occurring in local inflammatory milieu such as atopic lesions.

Three soluble form messages of murine CD46 are produced through alternative mRNA splicing

Murine CD46 (mCD46) is a type 1 membrane protein expressed predominantly in testicular germ cells, the distribution profile of which is in contrast to that of human CD46 showing a ubiquitous tissue distribution. We have identified an additional message of mCD46 that encodes a putative secretory form [Nomura et al. (1999) Immunogenetics 50, 245-254]. Here, we cloned three cDNAs encoding putative soluble CD46 from murine testis. These soluble form messages were yielded on insertion of unidentified nucleotide sequences, 77, 179, and 73 ntds, into the junctions between the SCR3 and SCR4 (variant 2), ST(c) and UK (variant 3), and SCR4 and ST(c) (variant 1) domains, respectively, the last one corresponding to the reported soluble form. The exons corresponding to these three inserts were identified in the murine CD46 genome, indicating that the alternative splicing of mRNA participates in the generation of these various CD46 messages. In normal mouse sera and cell lines, however, virtually no soluble CD46 was detected on immunoblotting. On Northern blotting analysis with specific probes, on the other hand, variant 1 was found to be predominantly expressed in the liver and heart. In addition, all variant messages were detected on PCR in all organs examined. When a rabbit cell line, RK13 cells, was transfected with cDNA of variant 1, protein synthesis was detected on immunoblotting. Although the mCD46 protein production was inefficient, this variant 1 exhibited factor I-cofactor activity as to inhibition of the complement cascade. Since the mCD46 protein was reported to be markedly up-regulated on infection of murine cells with mCMV, the soluble mCD46 proteins may act as a complement regulator that controls the systemic complement system under the conditions of a viral infection.

Interferon gamma-producing ability in blood lymphocytes of patients with lung cancer through activation of the innate immune system by BCG cell wall skeleton

An in vitro assay system was developed to assess the potency of the human innate immune system by measurement of IL-12, IL-18, IL-10 and IFNgamma in the supernatants of bacillus Calmette-Guerin cell wall skeleton (BCG-CWS)-stimulated blood samples. BCG-CWS is a ligand for Toll-like receptor (TLR) 2 and 4, and activates monocytes to macrophages (Mphi), and immature dendritic cells to mature antigen-presenting cells (APC). This system was found to allow the discrimination of immune suppressive states in patients with lung cancer from normal immune states in light of the cytokine profile. The following results were deduced from analyses of BCG-CWS-stimulated blood samples of lung cancer patients with reference to normal subjects. (1) The levels of production of IFNgamma and IL-10 by lymphocytes were decreased. (2) IL-12 p40 production by monocytes/Mphi was upregulated, while that of IL-10 was downregulated. (3) IL-18 was detected in all patients in a range similar to normal subjects. (4) Responses of lymphocytes to IL-2 and IL- 18 in terms of IFNgamma production were diminished. (5) The upregulated IL-12 levels were recovered to within the normal range in most patients after tumor resection. (6) Male patients showed more severe suppression of IL-12/IL-18-mediated IFNgamma production than female patients. Thus, the lesser IFNgamma production observed in patients' blood with high IL-12 p40 levels in response to BCG-CWS may reflect the production of p40 dimers or IL-23 instead of p70, or the presence of some unknown pathways to prohibit the interface between the innate and acquired immune systems. BCG-CWS-mediated Toll signaling may participate in IFNgamma induction for lymphocytes through Mphi/APC IL-12/I-18 modulation.

Distribution of IL-18 and IL-18 receptor in human skin: various forms of IL-18 are produced in keratinocytes

Human interleukin-18 (IL-18) enhances IL-12-mediated IFN-gamma production by lymphocytes and Fas/perforin-mediated cytolysis by NK cells. IL-18 is synthesized as a 24 kDa proform, and the proform is processed in the cytoplasm into an 18 kDa mature form. Active and precursor forms of IL-18 have been detected in immunocompetent cells, and active IL-18 exerts its functions through its receptor. We sought to determine which human skin cells are responsible for production of IL-18 and which express its receptor. Monoclonal antibodies against human IL-18 and polyclonal antibody against IL-18 receptor were provided for this analysis. Formalin-embedded and frozen sections of human epidermis were analyzed by immunoperoxidase and immunofluorescence staining. IL-18 was detected in all living cell layers of the epidermis, hair follicles, arrectores pilorum, eccrine ducts and endothelial cells. IL-18 was localized in the cytoplasm of cells in living epidermal cell layers. In contrast, IL-18 receptor was mainly detected in keratinocytes and expressed in the cell periphery in living cell layers. Since keratinocytes were the main source of IL-18 and its receptor, cultured human keratinocytes were further analyzed by immunoblotting. IL-18 receptor was identified as an 80 kDa single band. The mature 18 kDa and precursor 24 kDa forms of IL-18 were detected by our monoclonal antibody (mAb) 21 and mAb 132, respectively, while only the 18 kDa form was detected by a commercial mAb, 125-2H. Cultured keratinocytes showed positive granular staining for IL-18 in the cytoplasm and positive staining for IL-18 receptor mainly in the cell periphery. Our findings indicate that mature IL-18, precursor IL-18 and IL-18 receptor are simultaneously expressed with different localizations by human epidermal keratinocytes. Keratinocytes might be activated by their own IL-18 in an autocrine or paracrine fashion.

An Alternative Form of IL-18 in Human Blood Plasma: Complex Formation with IgM Defined by Monoclonal Antibodies

Monoclonal Abs 21 and 132 were raised against human functionally inactive rIL-18, and plasma IL-18 levels were determined by the sandwich ELISA established with these mABS: Plasma IL-18, designated type 2, was detected by this ELISA, and the levels found were not consistent with those obtained with the commercially available kit for determination of functionally active IL-18 (type 1). Type 1 was detected in all volunteers, whereas type 2 was detected in approximately 30% of healthy subjects, and the levels of type 2 in their blood plasma were high (25-100 ng/ml) compared with those of type 1 (0.05-0.3 ng/ml). We purified IL-18 type 2 from blood plasma of volunteers with high IL-18 type 2 concentrations, and its M(r) was determined to be 800 kDa by SDS-PAGE and molecular sieve HPLC. The purified 800-kDa protein, either caspase-1-treated or untreated, expressed no or marginal IL-18 function in terms of potentiation of NK-mediated cytolysis and IFN-gamma induction, and it barely bound IL-18R-positive cells. N-terminal amino acid analysis indicated that the purified protein was IgM containing a minimal amount of IL-18 proform and its fragment. Again, the purified IgM from IL-18 type2-positive volunteers exhibited cross-reaction with mAb 21 against IL-18. This band was not detected with 125-2H, an mAb against functionally active IL-18. Hence, human IgM carries functionally inactive IL-18 forming a disulfide-bridged complex, and this IL-18 moiety is from 10- to 100-fold higher than the conventional type 1 IL-18 in blood circulation in approximately 30% normal subjects.

Effect of intranasal administration of Lactobacillus casei Shirota on influenza virus infection of upper respiratory tract in mice

In mice administered Lactobacillus casei strain Shirota (LcS) intranasally, potent induction of interleukin 12, gamma interferon, and tumor necrosis factor alpha, which play a very important role in excluding influenza virus (IFV), was evident in mediastinal lymph node cells. In this model of upper respiratory IFV infection, the titers of virus in the nasal wash of mice inoculated with 200 microg of LcS for three consecutive days (LcS 200 group) before infection were significantly (P < 0.01) lower than those of mice not inoculated with LcS (control group) (10(0.9 +/- 0.6) versus 10(2.1 +/- 1.0)). The IFV titer was decreased to about 1/10 of the control level. Using this infection model with modifications, we investigated whether the survival rate of mice was increased by intranasal administration of LcS. The survival rate of the mice in the LcS 200 group was significantly (P < 0.05) greater than that of the mice in the control group (69% versus 15%). It seems that the decrease in the titer of virus in the upper respiratory tract to 1/10 of the control level was important in preventing death. These findings suggest that intranasal administration of LcS enhances cellular immunity in the respiratory tract and protects against influenza virus infection.

Human macrophages produce dimeric forms of IL-18 which can be detected with monoclonal antibodies specific for inactive IL-18

We established two monoclonal antibodies (mAbs) which specifically recognize human 'functionally inactive' recombinant IL-18, and IL-18 protein polymorphism was examined using human monocytes and macrophages (M phi). In 6 day GM-CSF-treated M phi, an 'inactive' IL-18-recognizing mAb 21 detected the IL-18 proform (24 kDa) and a 48-kDa protein, which were gradually increased concomitant with maturation stage. Majority of the 24- and 48-kDa forms were barely detectable with other mAbs recognizing 'active' IL-18. No reagents including Toll stimulators up-regulated these IL-18 populations in M phi. The 21-recognizable IL-18 species were separated using an anion-exchanger column and their IFN gamma-inducing activity was assessed with human lymphocytes plus IL-12. Virtually no as yet known activity was detected with these IL-18 species. After processed with M phi proteases, an 18-kDa form was generated to express the IFN gamma-inducing activity, although the activity was far weaker than that of control 'active' IL-18. These observations suggested that large amounts of various IL-18 species are produced with monocyte-M phi differentiation and most of these IL-18 species are functionally 'inactive' in terms of the reported IL-18 function even after proteolytic 18-kDa conversion.

Serum IgE response to orally ingested antigen: a novel IgE response model with allergen-specific T-cell receptor transgenic mice

BACKGROUND

The mechanism by which orally ingested allergens elicit an IgE response remains unclear because there are few animal models available for investigation of this response.

OBJECTIVE

We tried to develop a murine model suitable for investigation of the IgE response to orally ingested allergens, which would allow us to identify T cells that could promote IgE production.

METHODS

Ovalbumin (OVA)-specific T-cell receptor transgenic mice were fed a diet containing OVA, and both the serum antibody response and cytokine production by splenocytes were examined.

RESULTS

Oral administration of OVA to transgenic mice led to an increase in the levels of both antigen-specific IgE and total IgE in the sera. Subsequent intravenous challenge of OVA-fed transgenic mice with OVA resulted in anaphylactic shock. Analysis of cytokine production by splenocytes revealed that high IL-4-producing T cells appeared in the spleen 1 week after the start of feeding the OVA diet. T cells from these mice were found to promote IgE secretion by BALB/c B cells in vitro. This helper activity and the levels of IL-4 secretion were diminished after long-term feeding. These findings suggest the possibility that the orally ingested antigen elicited a response by a subpopulation of T cells that produce high levels of T(H2)-type cytokines and that promote IgE secretion, and these same T cells were tolerized by the orally ingested antigen.

CONCLUSION

This experimental model with transgenic mice may be a useful tool for further studies of the cellular and molecular mechanisms of the T-cell and IgE responses to orally ingested antigens.

A comparative analysis of the antigenic, structural, and functional properties of three different preparations of recombinant human interleukin-18

We compared the structural and functional properties of three recombinant human interleukin-18 (rIL-18) preparations, commercially available (Pep rIL-18) and prepared in our laboratory (active and inactive, according to their ability to potentiate IL-12-mediated interferon-gamma [IFN-gamma] induction in lymphocytes). All three preparations showed multimer formation on SDS-PAGE/immunoblotting using monoclonal antibodies (mAb) against the inactive form of rIL-18. In contrast, only the 18-kDa bands were recognized in each sample by mAb against the active form of rIL-18. The amounts of multimers and the 18-kDa moiety of Pep rIL-18 resembled those of the inactive rather than the active form. Likewise, the reaction profile of Pep rIL-18 toward mAb was very similar to that of inactive but not active rIL-18 on sandwich ELISA. Pep rIL-18 potentiated IFN-gamma-inducing activity together with IL-12, but its potency was 100-fold less than that of the active rIL-18, and excess doses were required for its activity. The inactive rIL-18 showed virtually no IFN-gamma-inducing ability, but when reduced and reconstituted, it inhibited the IFN-gamma-inducing activity of active rIL-18. These results suggest that there are two categories of recombinant IL-18 that are structurally, functionally, and antigenically different, and the mAb 125-2H and 21 can discriminate these two IL-18 populations by recognizing the epitopes specifically expressed on active and inactive IL-18, respectively.

Membrane and secretory forms of mouse membrane cofactor protein (CD46) generated from a single gene through alternative splicing

A cDNA encoding a new secretory form of mouse membrane cofactor protein (MCP, CD46) was identified additionally to the membrane form cDNA. The secretory MCP, predicted from the cDNA sequence, consisted of the conserved four short consensus repeats (SCRs) plus a four amino acid-stretch. Unlike human MCP which comprises many isoforms, mouse MCP cDNA predicted a single isoform of membrane MCP with cytoplasmic tail 1 (CYT1) and serine/ threonine-rich domain C (ST(C)). To clarify the genomic origin and monomorphic alteration of these cDNAs, we cloned and analyzed a mouse genomic DNA harboring the full coding sequence of MCP from a 129/SV mouse genomic library. The mouse Mcp was a single gene approximately 50 kilobases long. Eleven of the 14 coding exons of the human MCP gene and intron-exon boundary sequences were found to be conserved in the mouse gene. The STC homologue but not the STA or STB homologue in the mouse exons was functional: the latter being due to deletions and lack of consensus sequences for splicing. The sequence equivalent to cytoplasmic tail 2 (CYT2) has not been identified in the Mcp genome. Thus, the three exons (ST(A), ST(B), and probably CYT2) responsible for the polymorphism of human MCP by differential splicing were missing in the mouse Mcp gene. Unlike the case in humans, no Mcp-related genes or pseudogenes were observed in the mouse genome. The single mouse Mcp gene was mapped to the R-positive H5 band of mouse Chromosome 1 by FISH. Strikingly, one alternative exon with 73 base pairs (encoding the four new amino acids and a TGA stop codon) was discovered between the SCRIV and the STC exons; alternative splicing causes the generation of the secretory form of mouse MCP. These results on mouse MCP, together with the information concerning other mouse SCR proteins, infer that the regulator of complement activation (RCA) gene cluster is genetically diverged between humans and mice.

Determination of reference values for total PSA, F/T and PSAD according to prostatic volume in japanese prostate cancer patients with slightly elevated serum PSA levels

BACKGROUND

For screening prostate cancer (CAP) using prostate-specific antigen (PSA), the indications of biopsies for patients showing slightly elevated PSA values are still controversial. Furthermore, the dependence of total PSA, free-to-total PSA ratio (F/T) and PSA density (PSAD) on prostatic volume in gray zone cases is unclear.

METHODS

By analyzing 1913 patients with a serum total PSA ranging from 2.0 to 20 ng/ml, we evaluated the correlation between total PSA and age or prostatic volume and positive predictive value (PPV) in each range for total PSA, age and prostatic volume. Then suitable reference values for total PSA, F/T and PSAD were decided according to prostatic volume.

RESULTS

There was no close correlation between PSA and age or volume. The PPV was high in the group with a prostatic volume of 10-30 ml. Prostatic volume was categorized into three groups, <20, 20-40 and > or =40 ml, and reference values for obtaining a sensitivity of 90% were proposed. The reference values of total PSA and PSAD were lowered and that of F/T was raised with increase in prostatic volume. The specificity was very low for the > or =40 ml group. The highest specificity of 36% in PSAD was obtained for the <20 ml group.

CONCLUSION

The reference values for total PSA, F/T and PSAD must be changed according to prostatic volume in order to maintain a sufficient diagnostic sensitivity of CAP. Of these parameters, PSAD showed a high specificity in the group with a prostatic volume of <40 ml.

Immunomodulatory function of lactic acid bacteria

Using mice, we found that oral administration of Bifidobacterium breve YIT4064 (B. breve) activated the humoral immune system, augmented anti-rotavirus IgA production or anti-influenza virus (IFV) IgG production and protected against rotavirus infection or influenza infection, respectively. Furthermore, when the B. breve was given to infants from an infant home, there was a significant reduction of the frequency of rotavirus shedding in stool samples during the administration of the bacteria. It was also found, again using mice, that oral administration of Lactobacillus casei strain Shirota (LcS) stimulated type 1 helper T (Th1) cells, activated the cellular immune system and inhibited incidence of tumors and IgE production. These results demonstrated that these two strains of lactic acid bacteria modulated the different immune systems each in its own way and prevented against various diseases.

The 3'-UT of the ubiquitous mRNA of human CD46 confers selective suppression of protein production in murine cells

Mice express CD46 protein and its approximately 1.5-kb mRNA only in the testicular germ cells, unlike primates and pigs which ubiquitously express CD46 and its approximately 4 kb mRNA. Human CD46 is not well expressed in transgenic mice carrying human CD46 cDNA. To analyze the mechanism of regulation of human CD46 expression in mouse cells, we cloned the long (ubiquitous approximately 4 kb, L-form) and short ( approximately 1.5 kb, S-form) forms of human CD46 cDNA whose size difference is due to a stretch of the 3'-UT. Transfection of either cDNA resulted in marked S-form-dependent protein generation in all mouse cell lines tested. In contrast, there were virtually no differences in protein synthesis between S- and L-form cDNA in the simian and swine cell lines. Quantitative mRNA analyses and luciferase reporter gene assays suggested that one major cause of this interspecies discrepancy is transcriptional regulation, i. e. selective suppression of the 4-kb mRNA leading to low levels of protein synthesis. Although other mechanisms such as mRNA stability and translational regulation may lead to the low expression levels of L-form-derived CD46 in mice, the silencer activity in the L-form 3'-UT appears to function in human CD46 transcriptional regulation in mice.

Immunomodulatory function of lactic acid bacteria

Using mice, we found that oral administration of Bifidobacterium breve YIT4064 (B. breve) activated the humoral immune system, augmented anti-rotavirus IgA production or anti-influenza virus (IFV) IgG production and protected against rotavirus infection or influenza infection, respectively. Furthermore, when the B. breve was given to infants from an infant home, there was a significant reduction of the frequency of rotavirus shedding in stool samples during the administration of the bacteria. It was also found, again using mice, that oral administration of Lactobacillus casei strain Shirota (LcS) stimulated type 1 helper T (Th1) cells, activated the cellular immune system and inhibited incidence of tumors and IgE production. These results demonstrated that these two strains of lactic acid bacteria modulated the different immune systems each in its own way and prevented against various diseases.

Lung adenocarcinoma in lymphocytic interstitial pneumonitis associated with primary Sjögren's syndrome

We experienced a rare case of lung adenocarcinoma associated with lymphocytic interstitial pneumonitis caused by primary Sjögren's syndrome. A 78-year-old woman was referred to our hospital because of progressive sicca syndrome and nodular opacities in the right lower lobe on chest radiograph. This patient was diagnosed as primary Sjögren's syndrome by a labial gland biopsy and classical clinical features including xerophthalmia, xerostomia and immunoserological findings. Pathological findings including immunohistochemical studies in a surgically resected lung revealed adenocarcinoma in lymphocytic interstitial pneumonitis associated with primary Sjögren's syndrome. There was no evidence of malignant lymphoma in the lymph nodes or resected lung tissue. Pulmonary involvement of Sjögren's syndrome is now regarded both clinically and histopathologically as a wide spectrum of lymphoproliferative disorders ranging from benign to malignant. However, lung cancer associated with primary Sjögren's syndrome, as in our case, has apparently not been reported previously.

Human MD-1 homologue is a BCG-regulated gene product in monocytes: its identification by differential display

BCG-CWS is a therapeutically potent immune activator which improves the prognosis of cancer patients. However, the targeting effector cells and molecules for BCG-CWS in the human immune system have not been determined. Here, we found that BCG-CWS activates human monocytes and concomitantly down-regulates expression of a human homologue of chicken MD-1 in the activated monocytes by differential display. According to a previous study, MD-1 forms a complex with the Toll family protein RP-105 on murine B cell lines to facilitate its stable expression. Thus, MD-1 may participate in regulation of innate immune activation on human monocytes. Our results, taken together with these recent findings regarding Toll family proteins, suggest that BCG-CWS acts on monocytes to modulate the human innate immune system via regulation of Toll family proteins.

Protection against influenza virus infection of mice fed Bifidobacterium breve YIT4064

Mice fed Bifidobacterium breve YIT4064 and immunized orally with influenza virus were more strongly protected against influenza virus infection of the lower respiratory tract than ones immunized with influenza virus only. The number of mice with enhanced anti-influenza virus immunoglobulin G (IgG) in serum upon oral administration of B. breve YIT4064 and oral immunization with influenza virus was significantly greater than that upon oral immunization with influenza virus only. These findings demonstrated that the oral administration of B. breve YIT4064 increased anti-influenza virus IgG antibodies in serum and protected against influenza virus infection. The oral administration of B. breve YIT4064 may enhance antigen-specific IgG against various pathogenic antigens taken orally and induce protection against various virus infections.