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In the present study, we have investigated the effects of phycocyanin, a biliprotein of Spirulina platensis, on mucosal and systemic immune responses and allergic inflammation in C3H/HeN and BALB/cA mice. To induce the antigen-specific antibodies in the peripheral lymphoid tissues such as Peyer's patches and mesenteric lymph nodes, biodegradable ovalbumin-entrapped poly (DL-lactide-co-glycolide) particles were used as an antigen. Two weeks after the onset of phycocyanin ingestion, mice were immunized with an aqueous ovalbumin (OVA) solution. Starting at one week after the primary immunization, the mice were subjected to oral immunization with the biodegradable OVA microparticles twice a week. IgA, IgE and IgG1 antibodies were determined by ELISA. The OVA microparticles of 4-microm diameter successfully induced antigen-specific antibodies. In the mice that received phycocyanin treatment for 6 wk, a marked increase in the antigen-specific, as well as the total, IgA antibody level was observed in the Peyer's patches, mesenteric lymph nodes and intestinal mucosa as well as in the spleen cells. Both antigen-specific IgG1 and IgE antibody levels in the serum were suppressed by ingestion of phycocyanin for 8 wk. However, inflammation of the small intestine, monitored as vascular permeability by the Evans blue-leaking method was reduced by phycocyanin at 6 wk, which preceded the suppression of antigen-specific IgG1 and IgE antibody production by 2 wk. These results suggest that phycocyanin enhances biological defense activity against infectious diseases through sustaining functions of the mucosal immune system and reduces allergic inflammation by the suppression of antigen-specific IgE antibody.

The effect of endogenous nitric oxide synthase (NOS) on cardiac contractility and architecture has been a matter of debate. A role for NOS in cardiac hypertrophy has recently been demonstrated by studies which have shown hypertrophic cardiomyopathy (HCM) with altered contractility in constitutive NOS (cNOS) knockout mice. Caveolin-3, a strong inhibitor of all NOS isoforms, is expressed in sarcolemmal caveolae microdomains and binds to cNOS in vivo: endothelial nitric oxide synthase (eNOS) in cardiac myocytes and neuronal nitric oxide synthase (nNOS) in skeletal myocytes. The current study characterized the biochemical and cardiac parameters of P104L mutant caveolin-3 transgenic mice, a model of an autosomal dominant limb-girdle muscular dystrophy (LGMD1C). Transgenic mouse hearts demonstrated HCM, enhanced basal contractility, decreased left ventricular end diastolic diameter, and loss and cytoplasmic mislocalization of caveolin-3 protein. Surprisingly, cardiac muscle showed activation of eNOS catalytic activity without increased expression of all NOS isoforms. These data suggest that a moderate increase in eNOS activity associated with loss of caveolin-3 results in HCM.

A 66-year-old man with hepatocellular carcinoma (HCC) showed marked thrombocytosis (110.7 x 10(4)/microl). Bone marrow (BM) aspirates demonstrated an increase of mature megakaryocytes (MgK). The serum thrombopoietin (TPO) level was increased to about 100-fold that of the normal level in the terminal stage. However, the platelet count gradually decreased to 13.5 x 10(4)/microl. The autopsy specimen revealed normoplastic BM with decreased MgK, mainly consisting of the immature type, and it was negative for tumor cells. Liver specimen showed markedly fatty metamorphosis. Immunohistochemical staining of TPO demonstrated that hepatocytes were weakly stained and HCC cells strongly stained, suggesting TPO-producing HCC.

Pinellic acid is a novel and potentially useful oral adjuvant when used in conjunction with intranasal inoculation of influenza HA vaccines. All stereoisomers of pinellic acid have been synthesized via regioselective asymmetric dihydroxylation, regioselective inversion, and stereoselective reduction, and their adjuvant activities were characterized. Among this series of isomers, 9S, 12S, 13S compound has the most potent adjuvant activity. Structure-activity relationships are discussed.

Juzen-taiho-to (a Japanese herbal medicine) has been traditionally administered to patients with anemia, neutropenia, or wasting syndrome. We previously attempted to isolate and purify the hemopoiesis-stimulatory components in Juzen-taiho-to extracts using an in vitro hemopoietic stem cell (HSC) assay method in which mouse HSCs can proliferate on a stromal cell line (MS-5). We have found that fatty acids (particularly oleic acid and linolenic acid) actively promote the proliferation of HSCs, and that the effect is mediated by stromal cells, rather than by any direct action on the HSCs. In the present study, we show, using human normal bone marrow cells (BMCs) and umbilical cord blood cells, that similar stimulatory effects are due to the presence of oleic acid and linolenic acid, which stimulate the proliferation of HSCs in stroma-based culture systems. Furthermore, a marked stimulatory effect was noted on BMCs from patients with Shwachman syndrome, which shows pancreatic and bone marrow dysfunctions. We also show the data on hemopoietic recovery after the administration of Juzen-taiho-to to a patient with Shwachman syndrome. These findings suggest that decreased fatty acid levels in the blood, caused by exocrine pancreatic insufficiency, induce bone marrow dysfunction in Shwachman syndrome.