Shigeo Yamashiro

Phenotypic and functional change of cytokine-activated neutrophils: inflammatory neutrophils are heterogeneous and enhance adaptive immune responses

Polymorphonuclear leukocytes (PMN) are the most abundant leukocytes, comprising about two‐thirds of peripheral blood leukocytes, and play major roles in innate immunity. In addition, PMN play critical roles in the development of adaptive immunity. Recently, defensins and other peptides pre‐stored in PMN granules were shown to attract monocytes, dendritic cells, and T cells, leading to the hypothesis that the release of PMN granular peptides may link innate and adaptive immunity. During the past several years, we have focused on an alternative hypothesis that activated PMN further differentiate and acquire new phenotypes and functions that enable them to link the two responses. To test our hypothesis, we have taken local and global approaches and have shown several key findings that support the hypothesis. The findings include the requirement for priming PMN by cytokines to induce the delayed expression of MCP‐1/CCL2, a signal for mononuclear cells, and the expression of new cell‐surface markers by such cytokine‐activated PMN. In the present manuscript, we focus on the phenotypic and functional changes that occur during PMN activation with selected cytokines. The results of our study indicate that inflammatory PMN are heterogeneous and play roles in not only innate but also adaptive immunity in response to stimuli released in injured tissues.

Discoidin domain receptor 1 isoform-a (DDR1a) promotes migration of leukocytes in three-dimensional collagen lattices

Although integrins are crucial for migration of leukocytes through endothelium, integrin‐independent mechanisms appear to take over and mediate the migration of leukocytes through extracellular matrix (ECM) in a three‐dimensional tissue microenvironment. Discoidin domain receptor (DDR) 1 is a receptor tyrosine kinase activated by collagen, the most abundant ECM protein. In the present study, we detected that peripheral blood mononuclear cells (PBMC) and polymorphonuclear neutrophils were induced to express DDR1 after incubation in RPMI 1640. The expression level of DDR1 in PBMC was increased further by stimulation with tumor necrosis factor‐ex, interleukin‐1β, granulocyte‐macrophage colony‐stimulating factor, lipopolysaccharide, or phytohemagglutinin, but not with interferon‐γ. In vivo, DDR1 mRNA was detectable in mononuclear leukocytes infiltrating human renal tumor tissue. Among three DDR1 isoforms, DDR1a was the major transcript in leukocytes. Functionally, overexpression of either DDR1a or DDR1b in THP‐1 cells resulted in increased adherence to collagen‐coated plates in a β1‐integrin independent manner. However, only DDR1a‐, but not DDR1b‐, overexpressing cells exhibited marked pseudopod extension and migrated successfully through three‐dimensional collagen lattices. Consequently, we propose that the interaction of DDR1a with collagen of the ECM results in a requisite intracellular signaling that enables leukocytes to migrate in a tissue microenvironment and participate in host defense.

MCP-1 is selectively expressed in the late phase by cytokine-stimulated human neutrophils: TNF-alpha plays a role in maximal MCP-1 mRNA expression.

Culture supernatants of phytohemagglutinin (PHA)‐stimulated human peripheral blood mononuclear cells (PHA‐sup) induced monocyte chemoattractant protein‐1 (MCP‐1) mRNA expression in human neutrophils. MCP‐1 mRNA was first detected by Northern analysis at 8 h, and the peak level was detected at 16 h and sustained until 72 h. Cycloheximide and genistein, but not pertussis toxin, inhibited the expression of MCP‐1 mRNA. Recombinant tumor necrosis factor α (TNF‐α) induced a low level MCP‐1 mRNA accumulation in neutrophils, and addition of anti‐TNF‐α IgG blocked 30–70% of MCP‐1 mRNA expression induced with PHA‐sup. PHA‐sup‐stimulated PMN synthesized and secreted 3.1 ± 1.3 ng/5 × 106 PMN MCP‐1 within the first 24 h. Hybridization of 32P‐labeled cDNA preparations to an array of human cytokine cDNAs further indicated that MCP‐1 mRNA was selectively up‐regulated in the late phase after stimulation with the PHA‐sup. J. Leukoc. Biol. 65: 671–679; 1999.

Improvement of quality of life in patients surgically treated for asymptomatic unruptured intracranial aneurysms

Objective: To compare the preoperative and postoperative health-related quality of life (QOL) and psychological state of patients with asymptomatic unruptured intracranial aneurysms (ICAs) who underwent elective surgery. Methods: Out of 67 patients who underwent neck clipping of ICAs, we assessed the QOL of 61 patients using Short Form-36 (SF-36); their psychological state was rated on the Hospital Anxiety and Depression Scale (HADS) before, 3 months, and 1 and 3 years after treatment. Results: The preoperative mean scores for each of the eight SF-36 domains except bodily pain were significantly lower in the study population than in the reference population. 14 (20.9%) patients experienced surgical complications defined as neurological deterioration and/or abnormal CT findings within 30 days of the operation. Despite some complications, the QOL of all operated patients returned to the mean level of the reference population 3 years after treatment. At 3 months after surgery, the scores for psychosocial activities and general health perception were transiently below the preoperative levels. According to the HADS, the patients experienced mild anxiety before the operation; it disappeared by the third postoperative month. Conclusions: Preoperatively, patients with unruptured ICAs reported a significantly decreased QOL. It further declined transiently after elective surgery, but it returned to the mean level recorded for the reference population within 3 years. Our findings suggest that these patients derived significant QOL benefits from their surgery. Hence subjective QOL issues should be considered in deciding whether treatment-related risks and their natural history, such as their potential rupture, warrant surgery of asymptomatic unruptured ICAs.

Intradermal injection of monocyte chemoattractant protein-1 induces emigration and differentiation of blood monocytes in rat skin.

Background: Monocyte chemoattractant protein-1 (MCP-1) is a potent chemoattractant for blood monocytes in vitro. Recent studies in MCP-1-transgenic mice revealed that the local production of MCP-1 caused monocyte infiltration. However, the kinetics of monocyte infiltration after the production of MCP-1 or the amount of MCP-1 necessary for monocyte recruitment are not known. Methods: We purified recombinant rat MCP-1 expressed in COS-7 cells, and injected it into rat skin. The infiltrating cells were examined by immunohistochemistry and ultrastructural peroxidase cytochemistry. Results: Rat recombinant MCP-1 had a molecular mass of approximately 30 kD and exhibited the peak monocyte chemotactic activity at 10–9 M. One microgram of MCP-1 caused intra- and extravascular accumulation of mononuclear cells 3 h after injection. The cells were ED1+, indicating they were blood monocytes. The infiltration of mononuclear cells peaked at 12–24 h, and most of them were TRPM-3+ and ED3+, characteristic to exudate macrophages. None of the cells expressed ED2 or Ki-M2R antigens, markers for resident macrophages, until 3 days after injection. There was no uptake of [3H]thymidine by the infiltrating cells. Ultrastructural peroxidase cytochemistry confirmed that the infiltrating cells were monocytes and exudate macrophages. The number of OX8+ lymphocytes also peaked at 12 h, consisting of approximately 9% of the total infiltrating cells. Conclusion: These results indicate that MCP-1 attracts blood monocytes as early as 3 h and the infiltrating monocytes differentiate into exudate macrophages in loco. However, this effect was transient and the infiltration of monocytes did not result in tissue damage.

Lymphocytic adenohypophysitis: Report of two cases

Two women with lymphocytic adenohypophysitis not related to pregnancy are reported on. In obtaining a differential diagnosis of lymphocytic adenohypophysitis preoperatively, it is useful to note swelling of the anterior hypophyseal tissue and the existence of a posterior pituitary lobe on sagittal sections of magnetic resonance imaging scans. Hypofunction of the anterior hypophyseal gland is more severe in lymphocytic adenohypophysitis than in pituitary adenomas. Marked adhesion of fibrotic pituitary capsule to the dura is a characteristic observation during surgery for lymphocytic adenohypophysitis.

Cavernous malformation of the optic chiasm: case report

We report a 14-year-old boy with cavernous malformation of the optic chiasm. He had a 2-year history of gradually worsening visual disturbance. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a suprasellar mass, findings compatible with craniopharyngioma. The mass was biopsied and histological examination confirmed cavernous malformation. On the second day after the biopsy, he suffered chiasmal apoplexy due to intratumoural haemorrhage, lost visual acuity and developed a field cut. Cavernous malformations arising from the optic nerve and chiasm are extremely rare; only 29 cases have been reported to date. Most patients manifested acute visual acuity and visual field disturbances. Although MRI findings of cavernous malformations in the brain parenchyma have been reported, MRI findings on the optic nerve and chiasm may not be completely diagnostic. Of the 29 documented patients, 16 underwent total resection of the lesion without exacerbation of their preoperative symptoms; in some cases, resection was complicated by risk of damage to the surrounding neural tissue. As patients may suffer intratumoural haemorrhage after biopsy or partial removal of the lesion, the advisability of surgical treatment of cavernous malformations of the optic nerve and chiasm must be considered carefully.

Effectiveness of Endoscopic Surgery for Comatose Patients with Large Supratentorial Intracerebral Hemorrhages

To evaluate the effectiveness of endoscopic surgery for life-threatening large brain hemorrhage, we reviewed our empirical cases of comatose patients with large supratentorial intracerebral hemorrhage. Among 35 patients with putaminal or subcortical hemorrhage that was evacuated endoscopically, 14 cases (40%) presented both findings of neurological grade IV for severity and hematoma volume exceeding 70 mL in the recent 3 years (endoscope group), whereas 8 cases with the same conditions were treated by conventional craniotomy for the preceding 3-year period (craniotomy group). Between these two groups, mean age was higher and duration of surgery was shorter in the endoscope group, but no significant differences in hematoma size or evacuation rate were recognized. In the 10 cases that presented with signs of cerebral herniation (neurological grade IVb) and required emergent decompression, the preparation time for surgery tended to be shorter in the endoscope group, although the difference was not significant. Additional ventricular drainage was performed in 7 cases and showed a supplemental effect of reducing intracranial pressure (ICP). Consequently, all patients in the endoscope group were rescued without decompressive large craniectomy, even with symptoms of cerebral herniation. In conclusion, endoscopic surgery has the potential to offer an effective therapeutic option for comatose patients with large supratentorial intracerebral hemorrhages, matching conventional craniotomy for emergent treatment in terms of mortality and management of ICP.

Palliative lumboperitoneal shunt for leptomeningeal metastasis–related hydrocephalus: A case series

Background: Leptomeningeal metastasis–related hydrocephalus causes distress to patients with end-stage cancer through headache and other symptoms by elevating intracranial pressure, thus reducing quality of life. Ventriculoperitoneal shunt has been used as a treatment option in palliative care. We review four cases of patients who underwent lumboperitoneal shunt for leptomeningeal metastasis–related hydrocephalus. Cases: All patients suffered from severe headache and nausea. The primary lesion was histologically diagnosed as lung adenocarcinoma in each case. The duration from diagnosis to onset of hydrocephalus symptoms ranged from 0 to 52 (mean 26) months. Cerebrospinal fluid pressure in every case was above the normal range due to high intracranial pressure. Case management: Conventional procedures for lumboperitoneal shunt were employed for all patients. Adjustable pressure valves were retrofitted into the shunt system. Case outcome: Three patients demonstrated significant improvement of clinical symptoms and quality of life after placement of lumboperitoneal shunts. In two cases, not only did performance status improve to independent daily activity but also comparatively long-term survival was achieved due to subsequent chemotherapies after surgery. No symptoms of peritoneal dissemination by floating cancer cells in cerebrospinal fluid were seen in any patients. Conclusion: Lumboperitoneal shunt appears to improve quality of life if the patient is suffering from symptoms of leptomeningeal metastasis–related hydrocephalus. Compared to ventriculoperitoneal shunt, lumboperitoneal shunt is less invasive and simpler, providing a suitable option for frail patients with end-stage cancer. Adjustable pressure shunt valves can cope with varying symptoms and ventricle sizes.

Reporter/Functional gene transfer in rat brain.

Of the many methods and techniques for in vivo gene transfer, some have already been used in clinical trials. In most cases, genes are transferred into tissues using the infectivity of viral particles. However, viral systems have some known drawbacks (1,2). If an efficient and specific transfer method could be developed, naked plasmid DNA would be an ideal system for gene transfer. Plasmid-mediated methods would be economical and easy. Also, the transfer procedure could be easily repeated, as naked plasmid DNA has little antigenicity for the host (3,4).