Absence of donor-type major histocompatibility complex class I antigen-bearing microglia in the rat central nervous system of radiation bone marrow chimeras

Localization of bone marrow-originated cells in the central nervous system (CNS) of the rat was investigated by using bone marrow chimeras. In order to do this, Lewis rats which carry major histocompatibility complex (MHC) class I antigens haplotype 1 (RT1.Al) were reconstituted with (Lew X PVG)F1 (RT1.Al/c) bone marrow cells after lethal irradiation. Transferred bone marrow cells were detected by immunohistochemical staining using a monoclonal antibody, OX27, specific for haplotype c of rat MHC class I antigens (RT1.Ac). The spleen and thymus of chimeric rats were fully reconstituted with transferred F1 cells 4 weeks after bone marrow transplantation. At this stage, mononuclear cells in the subarachnoid space of the CNS expressed OX27 antigen indicating that they were of bone marrow origin. A few OX27-positive blood cells were scattered in the CNS parenchyma 4-12 weeks after reconstitution. Ramified microglia, however, remained OX27-negative. Bone marrow-derived microglia were not observed throughout the period of examination until 24 weeks. In addition, experimental allergic encephalomyelitis (EAE) was induced in chimeric rats in order to augment the expression of MHC class I antigens on microglia. Even under this condition, no OX27-positive microglia were observed. Taken together, ramified microglia might be of neuroectodermal origin and there is little possibility that the microglia are derived from the bone marrow. However, if the ramified microglia are derived from blood cells, the microglia may be expected to have characteristic cell kinetics from the following points: (1) the precursor cells of the microglia may enter the CNS only at the perinatal stage; and (2) even under the condition in which lymphocytes and macrophages enter the CNS as observed in EAE, the precursor cells of the microglia are not supplied from the blood.     

Angiotensin I-converting enzyme inhibitor improves reactive hyperemia in elderly hypertensives with arteriosclerosis obliterans.

Endothelial function in elderly hypertensive patients with arteriosclerosis obliterans has not been evaluated. We examined whether antihypertensive drugs improve vasodilatory response to reactive hyperemia of the limbs in elderly hypertensive patients (83 +/- 8 [SD] years) without (n=46, 0.9 < or = ankle-brachial pressure index < or = 1.4) and with (n=24) arteriosclerosis obliterans (ankle-brachial pressure index < 0.2). Patients were randomized for treatment with monotherapy of either temocapril (14 with and 26 without arteriosclerosis obliterans) or amlodipine (10 with and 20 without arteriosclerosis obliterans) for 6 months. Blood flows of the forearms and legs were measured by strain-gauge plethysmography. The vasodilatory response to the release of compression of the forearms and thighs at 200 mmHg or 20 mmHg more than systolic blood pressure for 5 min and to sublingual administration of nitroglycerin (0.3 mg) was assessed. The maximum reactive hyperemic flow in 35 legs with arteriosclerosis obliterans was significantly (p < 0.001) decreased compared to the value in legs in the control hypertensive subjects. Moreover, maximum reactive hyperemic flow in the forearms of patients with arteriosclerosis obliterans was significantly (p = 0.002) decreased compared to that in the control subjects. Blood pressure was similarly decreased by treatment with temocapril or amlodipine. Response to nitroglycerin (0.3 mg) was not changed by either drug. Treatment with temocapril significantly improved maximum reactive hyperemic flow of not only the legs and forearms in control hypertensives but also the legs and forearms in patients with arteriosclerosis obliterans, and attenuated the worsening of activity of daily living in these patients, although treatment with amlodipine did not. These results suggest that the angiotensin-converting enzyme inhibitor temocapril has a beneficial effect on endothelial function in elderly patients with arteriosclerosis obliterans.     

Modified Two-Layer Preservation Method (M-Kyoto/PFC) Improves Islet Yields in Islet Isolation

Islet allotransplantation can achieve insulin independence in patients with type I diabetes. Recent reports show that the two-layer method (TLM), which employs oxygenated perfluorochemical (PFC) and UW solution, is superior to simple cold storage in UW for pancreas preservation in islet transplantation. However, UW solution has several disadvantages, including the inhibition of Liberase activity. In this study, we investigated the features of a new solution, designated M-Kyoto solution. M-Kyoto solution contains trehalose and ulinastatin as distinct components. Trehalose has a cytoprotective effect against stress, and ulinastatin inhibits trypsin. In porcine islet isolation, islet yield was significantly higher in the M-Kyoto/PFC group compared with the UW/PFC group. There was no significant difference in ATP content in the pancreas between the two groups, suggesting that different islet yields are not due to their differences as energy sources. Compared with UW solution, M-Kyoto solution significantly inhibited trypsin activity in the digestion step; moreover, M-Kyoto solution inhibited collagenase digestion less than UW solution. In conclusion, the advantages of M-Kyoto solution are trypsin inhibition and less collagenase inhibition. Based on these data, we now use M-Kyoto solution for clinical islet transplantation from nonheart-beating donor pancreata.     

Generation and characterization of a human monoclonal antibody that neutralizes diverse HIV-1 isolates in vitro.

OBJECTIVE: The purpose of this study was to develop and characterize human monoclonal antibodies (HuMAb) that neutralize HIV-1. DESIGN: Based upon previous studies involving the generation of HuMAb that neutralize other enveloped viruses, we thought it feasible to generate HuMAb that might neutralize HIV-1. METHODS: A HuMAb was generated by fusing splenic B-cells from an HIV-positive patient with a mouse myeloma cell line. Flow cytometry was used to determine surface reactivity of the HuMAb on HIV-infected and non-infected cells. Radioimmunoprecipitation was employed to elucidate the antigen recognized by the HuMAb. A cell survival assay was used to determine the ability of the HuMAb to neutralize divergent isolates of HIV-1 in the presence or absence of complement. A gp120-CD4 inhibition enzyme-linked immunosorbent assay (ELISA) was developed in order to initiate studies to determine the mechanism of neutralization by the HuMAb. RESULTS: An anti-HIV HuMAb was generated that neutralized two HIV-1 isolates (IIIB and MN) without complement and which neutralized one divergent isolate (RF) and one clinical isolate in the presence of complement. This HuMAb, designated S1-1, was found, by flow cytometric analysis, to react with the surface of HIV-1-infected but not with uninfected cells. Radioimmunoprecipitation analysis demonstrated that S1-1 binds to native HIV gp120, but not dithiothreitol (DTT)-treated gp120. In addition, HuMAb S1-1 did not bind to denatured HIV antigens in Western blot analysis. HuMAb S1-1 effectively inhibited the binding of gp120 to soluble CD4 in ELISA. CONCLUSIONS: These results suggest that the epitope recognized by S1-1 is conformational and conserved among diverse HIV-1 isolates and may represent an uncharacterized HIV neutralizing domain within or close to the CD4 binding domain on gp120. HuMAb S1-1 might have a role to play in vaccine development or passive immunotherapy.     

Nutritional condition and absorptive capacity of 14 infants with short bowel syndrome

We examined the absorptive capacity and the nutritional condition of 14 infants with short bowel syndrome, whose residual small intestine was 90 cm or less. Their age ranged from 1 year to 18 years. Examined items were body weight, height, serum albumin, total cholesterol, triglyceride, fat soluble vitamins, trace elements and rapid turn over protein as markers of the nutritional condition. Fecal fat, fecal bile acid, d-xylose absorption test, sugar-, amino acid-evoked potential difference in the small intestine and disaccharidase activity of the mucosa were examined as markers of the absorptive capacity. Our results showed that the body weight was below the normal range in the patients with small intestine of less than 50 cm. Most nutritional markers were within normal range, however, cholesterol and vitamin D were low in the patients with fat malabsorption, especially in patients with less than 50 cm of small intestine. Fecal bile acid was higher than the normal range in all the patients. Potential difference was in normal range or slightly lower than normal in all the patients. We concluded that infants with less than 50 cm of small intestine had malabsorption of sugar, protein and fat. Therefore, prolonged nutrient support, especially fat, is necessary.     

Disappearance of Philadelphia chromosomes after remission induction in lymphoid crisis of chronic myelogenous leukemia]

The authors report a rare case of chronic myelogenous leukemia (CML) in which the Ph1 clone disappeared after remission induction of lymphoid crisis. A 58-year-old man was admitted to our hospital because of fever in July 1988. The white cell count was elevated. Bone marrow aspirate showed hypercellularity with myeloid hyperplasia. In the chromosomal analysis, Ph1 chromosomes were detected in 100% of bone marrow cells analysed. Diagnosis of CML was made and treatment was initiated with recombinant interferon-alpha 2a. Hematological remission without cytogenetic improvement was achieved. In March 1990 he developed lymphoid crisis with proliferation of CD10-positive cells. The chromosomal analysis revealed additional abnormalities including, 45, X, -Y, t(9;22) (q34;q11), +1, -8. With vincristine 0.6 mgX4, pirarubicin 15 mgX4, dexamethasone 40 mgX4 therapy complete remission was obtained. In December 1990 the Ph1 positive clone completely disappeared judging from normal karyotypes in the chromosomal analysis and the disappearance of M-bcr gene rearrangement.     

Intracranial arterial vasospasm associated with pituitary apoplexy after head trauma--case report.

A case of intracranial arterial vasospasm caused by pituitary apoplexy after head trauma is reported. In this case, pituitary apoplexy was secondary to head trauma, and the vasospasm was thought to be due to subarachnoid hemorrhage from a pituitary tumor. No such case has previously been reported in the literature.