Invasive Ductal Carcinoma of the Breast with a Large Central Acellular Zone Associated with Matrix-producing Carcinoma

Matrix-producing carcinoma is a variant of metaplastic carcinoma of the breast that consists of overt carcinoma with direct transition to a cartilagenous and osseous stromal matrix. A clinicopathological association between MPC and high-grade invasive ductal carcinoma with a large central acellular zone has been recently discussed. However, few reports have ever shown the radiological, pathological and immunohistochemical correlation of this unique tumor. We present a case of 27-year-old woman with matrix-producing carcinoma with a large central acellular zone, which was characterized by a large homogeneous hypodense center with well-marginated, ring-like enhancement on contrast enhanced computerized tomography.

Interleukin-7 Dose-Dependently Restores Parenteral Nutrition–Induced Gut-Associated Lymphoid Tissue Cell Loss but Does Not Improve Intestinal Immunoglobulin A Levels

BACKGROUND

Without enteral nutrition, the mass and function of gut-associated lymphoid tissue (GALT), a center of systemic mucosal immunity, are reduced. Therefore, new therapeutic methods, designed to preserve mucosal immunity during parenteral nutrition (PN), are needed. Our recent study revealed that exogenous interleukin-7 (IL-7; 1 microg/kg twice a day) restores the GALT cell mass lost during intravenous (IV) PN but does not improve secretory immunoglobulin A (IgA) levels. Herein, we studied the IL-7 dose response to determine the optimal IL-7 dose for recovery of GALT mass and function during IV PN. We hypothesized that a high dose of IL-7 would increase intestinal IgA levels, as well as GALT cell numbers.

METHODS

Male mice (n = 42) were randomized to chow, IL-7-0, IL-7-0.1, IL-7-0.33, IL-7-1 and IL-7-3.3 groups and underwent jugular vein catheter insertion. The IL-7 groups were fed a standard PN solution and received IV injections of normal saline (IL-7-0), 0.1, 0.33, 1, or 3.3 microg/kg of IL-7 twice a day. The chow group was fed chow ad libitum. After 5 days of treatment, the entire small intestine was harvested and lymphocytes were isolated from Peyer's patches (PPs), intraepithelial (IE) spaces, and the lamina propria (LP). The lymphocytes were counted and phenotypes determined by flow cytometry (alphabetaTCR, gammadeltaTCR, CD4, CD8, B cell). IgA levels of small intestinal washings were also examined using ELISA (enzyme-linked immunoabsorbent assay).

RESULTS

IL-7 dose-dependently increased total lymphocyte numbers in PPs and the LP. The number of lymphocytes harvested from IE spaces reached a plateau at 1 microg/kg of IL-7. There were no significant differences in any phenotype percentages at any GALT sites among the groups. IgA levels of intestinal washings were significantly higher in the chow group than in any of the IL-7 groups, with similar levels in all IL-7 groups.

CONCLUSIONS

Exogenous IL-7 dose-dependently reverses PN-induced GALT cell loss, with no major changes in small intestinal IgA levels. IL-7 treatment during PN appears to have beneficial effects on gut immunity, but other therapeutic methods are needed to restore secretory IgA levels.

Lack of Enteral Nutrition Delays Nuclear Factor Kappa B Activation in Peritoneal Exudative Cells in a Murine Glycogen-Induced Peritonitis Model

BACKGROUND

Early enteral nutrition is associated with a lower incidence of intraabdominal abscess in severely injured patients than parenteral nutrition (PN). We explored the underlying mechanisms by examining the influence of nutrition route on nuclear factor kappaB (NFkappaB) activation in peritoneal exudative cells (PECs) and peritoneal cytokine levels.

METHODS

Thirty male Institute Cancer Research mice were randomized to chow (n = 10), IV PN (n = 10), or intragastric (IG) PN (n = 10) and fed for 5 days. PECs were harvested at 2 or 4 hours after intraperitoneal injection of 2 mL of 1% glycogen. Intranuclear NFkappaB activity in PECs was examined by laser scanning cytometry. Cytokine (tumor necrosis factor-alpha [TNF-alpha], macrophage inflammatory protein-2 [MIP-2], interleukin-10 [IL-10]) levels in peritoneal lavaged fluid were determined by enzyme-linked immunosorbent assay.

RESULTS

Intranuclear NFkappaB at 2 hours was significantly higher in the chow and IG-PN groups than in the IV-PN group. TNF-alpha and IL-10 levels of the chow group were significantly higher than those of IV-PN mice at 2 hours, whereas those of IG-PN mice were midway between those of the chow and IV-PN groups. MIP-2 was significantly higher in the chow group than in the IG-PN and IV-PN mice at 2 hours. TNF-alpha levels correlated positively with intranuclear NFkappaB activity in PECs.

CONCLUSIONS

Enteral nutrition may improve peritoneal defense by preserving early NFkappaB activation in PECs and cytokine responses.

5-Fluorouracil Infusion Reduces Gut-Associated Lymphoid Tissue Cell Number and Mucosal Immunoglobulin A Levels

BACKGROUND

Anticancer drugs have been demonstrated to affect gut mucosal morphology and cause gastrointestinal symptoms. We hypothesized that even small doses of 5-fluorouracil (5-FU) would reduce gut-associated lymphoid tissue (GALT) mass and function.

METHODS

Mice underwent IV cannulation and received continuous infusion of normal saline or 10 mg/kg of 5-FU for 5 days. GALT cell numbers, phenotypes, and mucosal immunoglobulin A (IgA) levels were measured.

RESULTS

During the infusion, there were no significant differences in food intake or body weight change between the 2 groups. Cell yields from the intraepithelial space and lamina propria of the small intestine were lower in the 5-FU than the control group. The lamina propria CD4/CD8 ratio was reduced in the 5-FU compared with the control group. Intestinal and respiratory tract IgA levels were lower in the 5-FU than in the control group.

CONCLUSIONS

A small dose of 5-FU reduces GALT cell number and mucosal IgA levels, regardless of food intake.

Hemoperfusion with polymyxin B-immobilized fibers reduced the number of CD16+CD14 + monocytes in patients with septic shock

Background: CD16 +CD14+ monocytes dramatically increase in number in patients with severe infection. Hemoperfusion with PMX-F (direct hemoperfusion with polymyxin B immobilized fibers) has been reported to be a safe and effective treatment for patients with septic shock, although the molecular mechanism that accounts for its effectiveness is still unclear. The purpose of this study was to quantify the number of CD16+CD14+ monocytes in patients with an intra-abdominal infection and to evaluate the effects of PMX-F treatment on clinical parameters and leukocyte surface antigen expression in these patients.

Materials and Methods : Seventeen septic patients who had an intra-abdominal infection were enrolled in this study; 7 of these patients received PMX-F treatment. Peripheral blood samples were obtained immediately after admission, and were also collected from the above 7 patients before, during, and immediately after their PMX-F treatment. The expression of CD14, CD16, and Toll-like receptor (TLR)-4 on these patients' monocytes was evaluated using flow cytometry. In addition, lipopolysaccharide (LPS)-induced production of TNF-α and IL-1β by these cells was measured by ELISA.

Results: Monocytic expression of CD16 and TLR-4 was significantly greater in septic patients than in healthy controls, and their proportion of CD16+CD14 + monocytes was similarly elevated. LPSinduced production of TNF-α and IL-1β by peripheral blood mononuclear cells (PBMCs) of septic patients was significantly reduced compared to controls. Furthermore, there was a reduction in the proportion of CD 16+CD 14+ monocytes during PMX-F treatment, and in the expression of TLR-4 on monocytes after PMX-F treatment.

Conclusions: These results showed that the number of peripheral blood CD16+CD14 + monocytes and monocytic TLR-4 expression were markedly increased, and the production of pro-inflammatory cytokines in response to LPS significantly reduced in patients with sepsis. PMX-F treatment was found to be effective in reducing the number of CD 16+CD 14+ monocytes and in decreasing the monocytic expression of TLR-4 in patients with septic shock.

Effect of anastrozole and tamoxifen on lipid metabolism in Japanese postmenopausal women with early breast cancer

Endocrine therapies that profoundly decrease estrogen levels potentially have a detrimental effect on the cardiovascular system. This study evaluated the effect on lipid metabolism of one such agent, the new generation aromatase inhibitor anastrozole, compared with tamoxifen, when used as adjuvant treatment in postmenopausal Japanese women with early breast cancer. All patients had completed primary surgery and were randomized to anastrozole 1 mg once daily (n=22) or tamoxifen 20 mg once daily (n=22). Anastrozole significantly reduced levels of triglycerides and remnant-like particle cholesterol, whereas tamoxifen significantly increased these. Activity of lipoprotein lipase and levels of high-density lipoprotein cholesterol significantly increased after anastrozole treatment. In contrast, activity of hepatic triglyceride lipase, also a key enzyme of triglyceride metabolism, significantly decreased following treatment with tamoxifen. We thus conclude that in our study anastrozole had a beneficial effect on lipid profiles of postmenopausal women with early breast cancer after 12 weeks of treatment.

Squamous cell carcinoma of the breast in the form of an intracystic tumor

Squamous cell carcinoma of the breast is thought to arise through metaplasia of ductal carcinoma cells. We report a case of pure squamous cell carcinoma of the breast with features of intracystic tumor, which was considered to have arisen from metaplastic squamous epithelial cells lining the cyst wall. A 71-year-old woman presented at our hospital with a 40 x 30-mm mass in the lower outer quadrant of the right breast. Mammography revealed a round, high-density mass, which had a mostly regular but partially irregular margin. Ultrasonography demonstrated a solid tumor with an irregular shape protruding into a cystic space, suspicious of intracystic carcinoma. Aspiration cytology confirmed squamous cell carcinoma. A modified radical mastectomy was performed. Histopathologically, the intracystic tumor was a pure squamous cell carcinoma. The epithelial cells lining the inner cyst wall showed mostly squamous metaplasia, and there was continuity between these cells and the squamous cell carcinoma. 13 months later, the patient is free of disease with no adjuvant therapy.

Influences of long-term antibiotic administration on Peyer's patch lymphocytes and mucosal immunoglobulin A levels in a mouse model

BACKGROUND

Long-term antibiotic administration is sometimes necessary to control bacterial infections during the perioperative period. However, antibiotic administration may alter gut bacterial flora, possibly impairing gut mucosal immunity. We hypothesized that 1 week of subcutaneous (SC) antibiotic injections would affect Peyer's patch (PP) lymphocyte numbers and phenotypes, as well as mucosal immunoglobulin A (IgA) levels.

METHODS

Sixty-one male Institute of Cancer Research mice were randomized to CMZ (cefmetazole 100 mg/kg, administered SC twice a day), IPM (imipenem/cilastatin 50 mg/kg x 2), and control (saline 0.1 mL x 2) groups. After 7 days of treatment, the mice were killed and their small intestines removed. Bacterial numbers in the small intestine were determined using sheep blood agar plates under aerobic conditions (n = 21). PP lymphocytes were isolated to determine cell numbers and phenotypes (CD4, CD8, alphabetaTCR, gammadeltaTCR, B220; n = 40). IgA levels in the small intestinal and bronchoalveolar washings were also measured with ELISA.

RESULTS

Antibiotic administration decreased both bacterial number and the PP cell yield compared with the control group. There were no significant differences in either phenotype percentages or IgA levels at any mucosal sites among the 3 groups.

CONCLUSIONS

Long-term antibiotic treatment reduces PP cell numbers while decreasing bacterial numbers in the small intestine. It may be important to recognize changes in gut mucosal immunity during long-term antibiotic administration.

Restoration of Natural IgM Production from Liver B Cells by Exogenous IL-18 Improves the Survival of Burn-Injured Mice Infected withPseudomonas aeruginosa

Pseudomonas aeruginosa is the most common bacterium of postburn infection. In the present study we investigated the immune mechanism of susceptibility to this type of postburn infection and also examined the efficacy of IL-18 treatment. C57BL/6 mice were challenged with P. aeruginosa on day 7 after burn injury. Although the burn-injured mice showed a poor survival rate after bacterial challenge, they retained their IFN-gamma production. The burned mice showed lower serum IgM levels and a poor IgM response following P. aeruginosa challenge in comparison with the sham mice, whereas IL-18 treatment after burn injury (alternate day injections for 1 wk) greatly improved the serum IgM levels, which are P. aeruginosa-independent natural IgM before bacterial challenge, thereby increasing the survival rate after the challenge. IL-18 treatment also induced specific IgM to P. aeruginosa in the sera 5 days after bacterial challenge in the burned mice. Interestingly, CD43(+)CD5(-)CD23(-)B220(dim) cells, namely B-1b cells, increased in the liver after the IL-18 treatment and were found to actively produce IgM in vitro without any additional stimulation. Furthermore, the IL-18 treatment up-regulated the neutrophil count and the C3a levels in the blood as a result of the increased IgM level, which may thus play a critical role in the opsonization and elimination of any invading bacteria. IL-18 treatment for the burned mice and their resultant natural IgM production were thus found to strengthen the host defense against P. aeruginosa infection.

Albumin infusion after reperfusion prevents gut ischemia-reperfusion-induced gut-associated lymphoid tissue atrophy

BACKGROUND

Our recent study clarified that gut ischemia-reperfusion (I/R) causes gut-associated lymphoid tissue (GALT) mass atrophy, a possible mechanism for increased morbidity of infectious complications after severe surgical insults. Because albumin administration reportedly reduces hemorrhagic shock-induced lung injury, we hypothesized that albumin treatment prevents GALT atrophy due to gut I/R.

METHODS

Male mice (n = 37) were randomized to albumin, normal saline, and sham groups. All groups underwent jugular vein catheter insertion. The albumin and normal saline groups underwent 75-minute occlusion of the superior mesenteric artery. During gut ischemia, all mice received normal saline infusions at 1.0 mL/h. The albumin group was given 5% bovine serum albumin in normal saline at 1.0 mL/h for 60 minutes after reperfusion, whereas the normal saline group received 0.9% sodium chloride at 1.0 mL/h. The sham group underwent laparotomy only. Mice were killed on day 1 or 7, and the entire small intestine was harvested. GALT lymphocytes were isolated and counted. Their phenotypes (alphabetaTCR, gammadeltaTCR, CD4, CD8, B220) were determined by flow cytometry.

RESULTS

On day 1, the gut I/R groups showed significantly lower total lymphocyte and B cell numbers in Peyer's patches and the lamina propria than the sham group. However, the albumin infusion partially but significantly restored these cell numbers. On day 7, there were no significant differences in any of the parameters measured among the 3 groups.

CONCLUSIONS

Albumin infusion after a gut ischemic insult may maintain gut immunity by preventing GALT atrophy.

Alternative tyrosine phosphorylation of signaling kinases according to hormone receptor status in breast cancer overexpressing the insulin-like growth factor receptor type 1

The insulin-like growth factor receptor type 1 (IGF1R) is suggested to play important roles in cancer cell growth through cross-talk with hormone receptors and growth factor receptors. However, its clinical significance in breast cancers in vivo is still unclear. We examined immunohistochemically the expression of IGF1R, phosphorylated-AKT (pAKT) and phosphorylated-ERK1/2 (pERK1/2) using tissue microarray slides containing 150 cases of primary breast carcinoma. Their mutual correlation and correlation with the status of hormone receptors epidermal growth factor receptor and human epidermal growth factor receptor type 2 were also investigated. IGF1R overexpression was detected in 71 cases (47%), and was correlated with lower nuclear grade (P = 0.03), positive estrogen receptor (ER) and/or progesterone receptor status (P = 0.002). pERK1/2 expression, detected in 53 cases (35%), was correlated with positive ER (P < 0.0001) and lower nuclear grade (P = 0.014). pAKT expression, detected in 88 cases (59%), was not correlated with nuclear grade, hormone receptors status or other clinical parameters. Of the 71 IGF1R-overexpressing tumors, pERK1/2 expression was detected in 27 (56%) of 48 ER-positive cases but in only four (17%) of 23 ER-negative cases (P = 0.022). In contrast, pAKT expression was constantly (64% or higher) detected irrespective of hormone receptor status in IGF1R-overexpressing breast cancers. Taken together, these findings suggest that IGF1R overexpression might activate pERK1/2 and pAKT in hormone receptor-positive breast cancer, but activate only pAKT in hormone receptor-negative breast cancer.

Efficacy of accelerated partial breast irradiation as a neoadjuvant treatment for patients with breast cancer: a pilot study

BACKGROUND

Breast conserving treatment (BCT) consists of breast-conserving operation and followed by whole-breast irradiation (WBI). Accelerated partial breast irradiation (APBI) is being considered as a possible alternative to WBI. Neoadjuvant APBI might provide more benefit than postsurgical APBI because tumor downstaging will enhance the likelihood of BCT.

METHODS

APBI was delivered as 50 Gy in 5 fractions over 5 days before operation for patients with breast cancer of 3 to 4 cm in diameter. Patients with tumors 3 cm or less were deemed to be candidates for breast-conserving operation.

RESULTS

Between September 1998 and August 1999, 12 women were enrolled. The mean tumor diameter and volume were reduced from 3.4 to 1.8 cm (reduction rate: 47%) and from 8.1 to 2.2 cm3 (reduction rate: 71%), respectively. The mean pathologic tumor size was 1.5 cm, and a complete pathologic response was found in 1 patient (8%). All patients were eligible for breast-conserving operation. No ipsilateral breast recurrences have been observed to date.

CONCLUSIONS

This is the first report of neoadjuvant APBI for relatively large breast cancers. Although the number of participants was small, these results would encourage the development of clinical trials exploring the efficacy of neoadjuvant APBI.

Differential toll-like receptor expression after ex vivo lipopolysaccharide exposure in patients with sepsis and following surgical stress

INTRODUCTION

Monocytes from septic patients have a reduced capacity to respond to lipopolysaccharide (LPS). We examined whether the same response occurred after surgical injury, and whether this reduced activity was associated with differential monocyte toll-like receptor (TLR) expression.

MATERIALS AND METHODS

Peripheral blood mononuclear cells (PBMCs) were isolated from septic patients, patients undergoing surgery, and healthy volunteers. Cells were stimulated ex vivo with LPS (1 microg/ml) and stained for CD14, CD16, TLR-2, TLR-4, and HLA-DR surface expression.

RESULTS

TLR-2 and -4 expressions were significantly increased in monocytes from both septic and surgical patients. While ex vivo LPS-stimulation significantly increased TNFalpha and IL-1beta production in PBMCs from surgical patients, LPS-stimulation decreased IL-1beta production from septic patients as compared to surgical and control patients. Ex vivo LPS-stimulation induced TLR-4 upregulation in monocytes from both surgical and control patients, but not from septic patients. HLA-DR expression in CD14+CD16+ monocytes was reduced only in septic patients.

CONCLUSIONS

PBMCs from septic patients, but not following surgical injury, have a reduced capacity to respond to a secondary inflammatory signal, but this defect is not associated with reduced TLR-4 or CD14 expression.

Dietary restriction compromises resistance to gut ischemia-reperfusion, despite reduction in circulating leukocyte activation

BACKGROUND

Gut ischemia-reperfusion (gut I/R) accompanying severe surgical insults leads to neutrophil-mediated injury and is regarded as a triggering event in early multiple-organ failure. Our previous study demonstrated dietary restriction to down-regulate leukocyte activation. Therefore, we hypothesized dietary restriction might be beneficial in terms of surviving I/R. We also evaluated leukocyte activation and the level of organ glutathione, an antioxidative substance.

METHODS

Institute of Cancer Research mice received chow, 170 (ad libitum), 119 (MR: mild restriction) or 68 (SR: severe restriction) g/kg per day for 7 days. Exp. 1: The mice (n = 59) underwent 15 or 45 minutes of gut ischemia and survival was observed. Exp. 2: The mice (n = 73) were killed before or 60 or 120 minutes after 15-minute ischemia. Reactive oxygen intermediate (ROI) production by circulating myeloid cells and CD11b expression was determined. Some mice were assessed for nuclear factor kappa B (NFkappaB) activation. Glutathione levels were measured in some of the small intestine and liver samples from each group.

RESULTS

Dietary restriction decreased survival. Circulating myeloid cell priming and activation, in terms of ROI production and CD11b expression, were enhanced in the ad libitum group but not in the restricted groups. NFkappaB was activated only in the ad libitum group. Gut and hepatic glutathione levels were lower in the SR than in the ad libitum group. Dietary restriction caused histologic damages in gut, liver, and lung 120 minutes after reperfusion.

CONCLUSIONS

Dietary restriction blunts leukocyte priming and activation after gut ischemic insult but worsens the outcome by, at least in part, decreasing antioxidative activities. Clinically, nutrition replenishment may be required to improve the outcome of gut hypoperfusion.

Multiple interleukin-18 injections promote both mouse Th1 and Th2 responses after sublethal Escherichia coli infection

Interleukin (IL)-18 is considered to induce exclusively the Th1 immune response but not the Th2 response in the presence of adequate IL-12 stimulation in bacterial infections. However, we demonstrate herein that multiple IL-18 injections to the mice not only enhance the early Th1 response but also stimulate the Th2 response later after viable Escherichia coli infection. Multiple IL-18 injections (three alternate-day injections) raised the serum interferon (IFN)-gamma level at 6 h and serum Th2 cytokine levels, such as IL-4, IL-10 and IL-13, at 48 h after infection, while a single IL-18 injection increased only the serum IFN-gamma level. Depletion of mouse CD4+ cells suppressed the IL-18-induced Th2 cytokines, IL-4, IL-10 and IL-13. In contrast, depletion of natural killer (NK)1.1+ cells reduced the IFN-gamma and IL-13 levels. Moreover, multiple IL-18 injections up-regulated the serum IgM level at 72 h after infection while a single IL-18 injection did not. Interestingly, neutralization of IL-4 but not IFN-gamma partially suppressed the increased serum IgM. Liver mononuclear cells (MNCs) from the mice treated with multiple IL-18 injections significantly increased more production of not only IFN-gamma but also Th2 cytokines and IgM by in vitro lipopolysaccharide (LPS) stimulation than those from the phosphate-buffered saline (PBS)-treated mice, while liver MNCs from the single IL-18-injected mice also increased IFN-gamma production but significantly suppressed IL-4 and IgM production compared to those from the PBS-treated mice. Our findings suggest that multiple injections of IL-18 up-regulate both the cellular and humoral innate immunities, thereby enhancing host defence against bacterial infections.

Route and type of nutrition influence nuclear factor kappaB activation in peritoneal resident cells

Morbidity of intra-abdominal abscess is increased when severely injured patients are fed parenterally. Lack of enteral nutrition appears to impair peritoneal cavity host defense. Because the transcription factor nuclear factor kappaB (NFkappaB) regulates various genes involved in inflammatory responses and its activation is important for host defense, we hypothesized that enteral nutrition would preserve appropriate NFkappaB activation in peritoneal resident cells (PRCs), the first defense line against peritoneal contamination. Mice (n = 105) were randomized to chow (n = 38), intravenous (IV)-total parenteral nutrition (TPN) (n = 34), or intragastric (IG)-TPN (n = 33) for 5 days' feeding. In experiment 1, PRCs were harvested for measurement of intranuclear NFkappaB activity with or without in vitro lipopolysaccharide (LPS) stimulation using laser scanning cytometry and enzyme-linked immunoabsorbant assay. PRC numbers tended to be higher in enterally fed mice than in IV-TPN mice. The main PRC subpopulation was macrophages in all groups. NFkappaB activation was increased in response to LPS in chow mice, whereas there was no increase in the IV-TPN group. IG-TPN mice demonstrated moderate NFkappaB activation. In experiment 2, mice underwent cecal ligation and puncture (CLP). Survival was observed up to 5 days. In another set of mice, tumor necrosis factor (TNF) alpha levels of peritoneal lavaged fluid were measured 4 h after CLP. Survival times after CLP improved in the chow and IG-TPN groups compared with the IV-TPN group. TNFalpha levels were significantly higher in the chow than in the IV-TPN group. In conclusion, parenteral nutrition decreases PRC number and blunts NFkappaB activation in PRCs. These changes may impair host defense in the peritoneal cavity.

Exploitation of interleukin-18 by gastric cancers for their growth and evasion of host immunity

Interleukin-18 (IL-18) is a pleiotropic cytokine that enhances Th1 or Th2 immune response. We show a novel mechanism of gastric cancer cells that allows their immune escape utilizing IL-18. All 4 gastric cancer cell lines, but not colon lines, constitutively expressed IL-18 receptors and IL-18 dose-dependently enhanced their in vitro proliferation accompanied by nuclear factor kappaB activation. When IL-18-pretreated gastric cancer cells were cultured with cytokine-activated peripheral blood killer lymphocytes, the antitumor machineries, perforin or interferon-gamma production of killer lymphocytes decreased, resulting in a decreased susceptibility of cancer cells to killer lymphocytes. Furthermore, gastric cancer cells cultured with IL-18 showed an increased expression of a granzyme B inhibitor, protease inhibitor 9. IL-18 injections into severe combined immuno-deficient mice intraperitoneally inoculated with gastric cancer cells consistently decreased the mouse survival time. Our results indicate that gastric cancers exploit IL-18 to grow/invade and evade immunosurveillance in the hosts.

Gut ischemia-reperfusion affects gut mucosal immunity: A possible mechanism for infectious complications after severe surgical insults*

OBJECTIVE

To examine influences of gut ischemia/reperfusion (I/R) on gut-associated lymphoid tissue (GALT) mass and function.

DESIGN

Prospective, randomized controlled study.

SETTING

Research laboratory.

SUBJECTS

Male Institute of Cancer Research mice.

INTERVENTIONS

Ninety mice were randomized to three groups: I/R (60-min gut ischemia), sham (laparotomy only), and control (no operation). On days 1, 2, 4, 7, and 10, mice were killed to harvest lymphocytes from Peyer patches, the intraepithelial space, and the lamina propria (LP) of the small intestine. Respiratory tract and small intestinal washings were also obtained.

MEASUREMENTS AND MAIN RESULTS

Gut I/R significantly reduced lymphocyte numbers in Peyer patches, the intraepithelial space, and the LP. The reduction was prominent in GALT effector sites, that is, the intraepithelial space and LP, but numbers recovered quickly in LP. Changes in cell numbers in Peyer patches, GALT inductive sites, were subtle but persistent. Gut I/R reduced B cell numbers in Peyer patches; alphabeta T cell receptor (TCR)+, gammadeltaTCR+, CD8+, and B cell numbers in the intraepithelial space; and gammadeltaTCR+, CD8+, and B cell numbers in the LP, in comparison with the sham or control group. There were no significant differences in respiratory tract immunoglobulin A levels between the I/R and sham groups. Intestinal immunoglobulin A was elevated on day 1 in the I/R group, with no significant difference after day 2 in comparison with the sham group.

CONCLUSIONS

Despite the maintained mucosal immunoglobulin A level, gut I/R markedly reduces GALT cell numbers, with changes in lymphocyte phenotypes. These alterations may be associated with increased morbidity due to infectious complications after severe surgical insults.

An in vitro Shwartzman reaction-like response is augmented age-dependently in human peripheral blood mononuclear cells

A lethal human septic shock model, mouse generalized Shwartzman reaction (GSR), was elicited by two consecutive lippolysaccharide (LPS) injections (24 h apart) in which interferon-gamma (IFN-gamma) induced by interleukin (IL)-12 played a critical role in the priming phase, and tumor necrosis factor (TNF) was an important effector molecule in the second phase. We recently reported IL-12/LPS-induced mouse GSR age-dependently enhanced. We herein demonstrate that human peripheral blood mononuclear cells (PBMC) from healthy adults/elderly, cultured with IL-12 for 24 h and with LPS for an additional 24 h, produced a much larger amount of TNF (which increased age-dependently) than did PBMC without IL-12 priming. Whereas macrophages mainly produced TNF following LPS stimulation, macrophages and lymphocytes were necessary for a sufficient TNF production. IL-12-induced IFN-gamma up-regulated Toll-like receptor 4 (TLR-4) on macrophages of adults. Although the PBMC from children produced a substantial amount of IFN-gamma after IL-12 priming, the GSR response, with augmented TNF production and an up-regulated TLR-4 expression of macrophages, was not elicited by LPS stimulation. CD56+natural killer cells, CD56+T cells, and CD57+T cells (NK-T cells), which age-dependently increased in PBMC, produced much larger amounts of IFN-gamma after IL-12 priming than that of conventional CD56-CD57-T cells and also induced cocultured macrophages to produce TNF by subsequent LPS stimulation. The elder septic patients were consistently more susceptible to lethal shock with enhanced serum TNF levels than the adult patients. The NK cells, NK-T cells, and macrophages, which change proportionally or functionally with aging, might be involved in the enhanced GSR response/septic shock observed in elderly patients.

EXOGENOUS INTERLEUKIN 7 AFFECTS GUT-ASSOCIATED LYMPHOID TISSUE IN MICE RECEIVING TOTAL PARENTERAL NUTRITION

In the absence of enteral nutrient delivery, gut-associated lymphoid tissue (GALT) mass and function are reduced. The purpose of this study was to examine whether exogenous interleukin (IL)-7 treatment reverses intravenous (IV)-total parenteral nutrition (TPN)-induced changes in GALT, immunoglobulin (Ig) A levels, and gut barrier function. Eighty-nine mice were randomized to chow, TPN, or TPN + IL-7 (1 microg/kg, administered IV twice a day) and treated for 5 days. The entire small intestine was harvested and lymphocytes were isolated from Peyer's patches (PPs), intraepithelial (IE) spaces, and the lamina propria (LP). Small intestinal and bronchoalveolar IgA levels were measured. Proximal and distal small intestinal levels of IgA-stimulating (IL-10) and IgA-inhibiting (IFNgamma) cytokines were determined with enzyme-linked immunoabsorbant assay. Moreover, 1 x 10 live Pseudomonas aeruginosa were delivered by gavage and survival was observed. TPN decreased total cell yields from PPs, IE spaces, and the LP compared with the chow group. IL-7 treatment restored cell numbers. PP CD4+, PP CD8+, IE gammadeltaTCR+, and LP CD4+ cell numbers were higher in the TPN + IL-7 group than in the TPN group. Secretory IgA levels were lower in the TPN and TPN + IL-7 than in the chow group. In the distal small intestine, IFNgamma levels were similar in the three groups, whereas IL-10 levels were reduced in the TPN and TPN + IL-7 groups relative to the chow group. Survival times were reduced in the TPN compared with the chow group, but IL-7 treatment significantly improved survival. Thus, exogenous IL-7 does not improve secretory IgA levels, nor are there any remarkable effects on levels of gut IgA-mediating cytokines. However, IL-7 treatment during TPN reverses TPN-induced GALT atrophy and improves survival in a gut-derived sepsis model.

Characterization of the expression of TLR2 (toll-like receptor 2) and TLR4 on circulating monocytes in coronary artery disease

TLRs are receptors involved in the recognition of pathogens by the innate immune system, and TLR2 and TLR4 play important roles in the activation of monocytes. A total of 105 consecutive patients who underwent coronary angiography comprised of 46 with stable effort angina (SA), 41 with unstable angina (UA), and 18 with no significant CAD (CNT) were enrolled. The baseline expression levels of TLR2 and TLR4 on monocytes in peripheral blood mononuclear cells (PBMCs) were determined by flow-cytometric analysis. Since TLR2 expression has been reported to be regulated by TLR4 signaling, we cultured PBMCs with or without lipopolysaccharide (LPS, 1 microg/ml). At baseline, TLR4 levels (mean of fluorescence intensity ) in SA (145 +/- 58, p < 0.05) and UA (164 +/- 65, p < 0.01) were higher than those in CNT (107 +/- 37). As for TLR2, levels were higher in UA (108 +/- 36, p < 0.05) than in SA (94 +/- 18) and CNT (87 +/- 22). After stimulation with LPS, TLR2 levels increased in SA but decreased in UA. In conclusions, TLR4 levels increased in both SA and UA. Monocytes in UA were characterized by elevated TLR2 levels and unresponsiveness of the TLR2 levels to TLR4 stimulation.

T lymphocyte numbers in human gut associated lymphoid tissue are reduced without enteral nutrition

BACKGROUND

Clinically, in the absence of enteral nutrition, the morbidity of infectious complication is high. Although experiments using mice have shown alterations in gut-associated lymphoid tissue (GALT) to be an important mechanism underlying impaired host defense, there are no clinical studies on the effects of nutritional routes on GALT.

METHODS

A total of 27 colon cancer cases who underwent right colectomy or hemicolectomy were reviewed. Six patients did not receive enteral nutrition for 4 to 28 days before surgery because of bowel obstruction (parenteral nutrition [PNI group). Twenty-one patients were enterally fed before surgery (enteral nutrition [EN] group). The terminal ileum from resected specimens was examined microscopically. T-cell numbers in intraepithelial spaces (IE) and the lamina propria (LP) were determined immunohistochemically in blinded fashion.

RESULTS

There were no significant differences in baseline characteristics between the 2 groups. T-cell number in the LP was significantly lower in the PN group than in the EN group, with no difference in IE cell numbers.

CONCLUSIONS

Lack of enteral delivery of nutrients reduces GALT cell number in patients with colon cancer, as is the case in mice.

Opposite effects of enhanced tumor necrosis factor-alpha production from Kupffer cells by gadolinium chloride on liver injury/mortality in endotoxemia of normal and partially hepatectomized mice

Gadolinium chloride (GdCl3) reportedly inhibits Kupffer cell function including TNF-alpha production and thereby improves organ dysfunctions after LPS challenge, particularly in partially hepatectomized (PH) mice. In addition, TNF-alpha reportedly promotes the regeneration of hepatocytes after PH. However, we have frequently seen GdCl3 treatment increase the mortality of normal mice after LPS injection. Therefore, we investigated this controversial issue in the present study. The mice treated by GdCl3 (10 mg/kg, i.v.) at 24 h before LPS challenge showed increased serum TNF-alpha and ALT levels after LPS challenge and a decreased mouse survival rate. The Kupffer cells from GdCl3-treated mice consistently produced a much larger amount of TNF-alpha following in vitro LPS stimulation than those of the control mice despite the fact that the Kupffer cells decreased in number and also demonstrated decreased superoxide production. Anti-TNF-alpha Ab before LPS-injection greatly improved GdCl3-induced mouse mortality and the degree of liver injury. In marked contrast, the increased amount of TNF-alpha induced by GdCl3 improved the survival after LPS challenge in PH mice because TNF-alpha promoted hepatocyte mitosis/regeneration in PH liver as evidenced by the fact that the inhibition of TNF-alpha before PH suppressed hepatocyte regeneration and decreased survival after LPS challenge. In conclusion, GdCl3 depletes the superoxide-producing Kupffer cells but conversely enhances the function of TNF-alpha-producing Kupffer cells, which thereby leads to LPS-induced mortality. Meanwhile, the increased TNF-alpha production induced by GdCl3 supports liver regeneration and increases the survival after LPS challenge in PH mice.

Neutrophil elastase, MIP-2, and TLR-4 expression during human and experimental sepsis

Highly activated neutrophils play a critical role in mediating organ injury in sepsis by releasing neutrophil elastase (NE). Toll-like receptors (TLRs) play an important role in the host defense against invading microbes, and their signaling pathway is critical to the activation of the proinflammatory response. However, the relationship between TLR expression and the host defense mechanism during sepsis has not been fully elucidated. In this paper, we investigated the relationships among chemokine (MIP-2), TLR-4, and NE expression in human sepsis and murine peritonitis (CLP). TLR-4 expression on monocytes/macrophages was examined in patients with sepsis and in murine peritonitis and was markedly increased in both populations. LPS-induced MIP-2 production by bronchoalveolar cells and liver mononuclear cells in mice with peritonitis was also significantly increased compared with sham-operated mice. Pretreatment of the macrophage cell line, RAW 264.7 cells, with a NE inhibitor before their exposure to LPS resulted in a significant dose-dependent decrease in MIP-2 production, which was comparable to that seen following pretreatment with TLR-4 antibody. Furthermore, NE and LPS both up-regulated TLR-4 expression on human peripheral blood monocytes. Thus, chemokine-induced recruitment of neutrophils in sepsis may result in further increased chemokine production and increased expression of TLR-4. Neutrophil-derived NE may be associated with increased expression of monocyte/macrophage TLR-4, thereby serving as a positive feedback loop for the inflammatory response among the different cell populations.

Critical role of the liver CD8+ CD122+ T cells in the generalized Shwartzman reaction of mice

We examined the role of mouse CD8+ CD122+ T cells, which increase in number with age, in the generalized Shwartzman reaction. This reaction was induced by IL-12 priming and subsequent LPS challenge (after 24 h) in mice of various ages (4-50 weeks of age). Although most young mice (4 or 6 weeks of age) survived, mortality essentially increased with increasing age of the mice, and all mice of 20 weeks of age or older died within 48 h. Serum TNF-alpha levels after LPS challenge also increased age dependently. The neutralization of either IL-12-induced IFN-gamma or LPS-induced TNF-alpha improved the survival of middle-aged (25-week-old) mice. Both IFN-gamma production after IL-12 priming and TNF-alpha production from the liver mononuclear cells after LPS challenge were also prominent in the middle-aged mice. CD8+CD122+ T cells cultured with IL-12 produced a much larger amount of IFN-gamma than CD8+CD122- T cells. Although the depletion of NK/NK T cells did not decrease the IFN-gamma or TNF-alpha production in the Shwartzman reaction of the middle-aged mice, an additional depletion of CD8+CD122+ T cells did decrease such production and also improved mouse survival. Furthermore, young mice transferred with CD8+CD122+ T cells from aged B6 nude mice showed an enhanced Shwartzman reaction.

L-arginine-enriched parenteral nutrition affects lymphocyte phenotypes of gut-associated lymphoid tissue

BACKGROUND

Experimentally, total parenteral nutrition (TPN) diminishes gut-associated lymphoid tissue (GALT) cell numbers and function. Although glutamine supplementation is known to reverse TPN-induced changes in GALT, effects of another conditionally essential amino acid, L-arginine (ARG), on GALT remain unclear.

METHODS

Twenty-two male Institute of Cancer Research mice were randomized to standard TPN (0.3% arginine, STD-total parenteral nutrition) or 1% ARG-enriched TPN (ARG-total parenteral nutrition). After 5 days of feeding, lymphocytes were harvested from Peyer's patches (PP), the lamina propria, and intraepithelial (IE) spaces of the small intestine to determine cell yields. Lymphocyte phenotypes (alphabetaTCR, gammadeltaTCR, CD4, CD8, and B220 as a B cell marker) were determined using flow cytometry. IgA levels in washings of the small intestine, upper respiratory tract, and lungs were measured with ELISA.

RESULTS

ARG-total parenteral nutrition did not affect lymphocyte yields. The percentages of CD4+ cells in PP and IE, and alphabetaTCR+ cells in PP, were significantly higher in the ARG-total parenteral nutrition than in the STD-total parenteral nutrition mice, without marked differences in other phenotypes examined. There were no significant differences in intestinal and respiratory tract IgA levels between the 2 groups of mice.

CONCLUSIONS

One percent ARG supplementation of TPN does not improve GALT cell number or mucosal IgA level but benefits to increase CD4+ cell percentages in GALT.

Effects of L-arginine infusion during ischemia on gut blood perfusion, oxygen tension, and circulating myeloid cell activation in a murine gut ischemia/reperfusion model

BACKGROUND

Gut hypoperfusion is considered to be a mechanism for early multiple-organ failure after severe surgical insults. L-Arginine (ARG) may preserve gut microcirculation as a substrate of nitric oxide synthase, but simultaneously may enhance immune cell response. It remains unknown if ARG infusion during gut ischemia improves the outcome after gut ischemia-reperfusion (I/R).

METHODS

Male Institute of Cancer Research mice were randomized to control and ARG groups. After i.v. cannulation, mice underwent 90 (Exp. 1) or 60 (Exp. 2 and 3) minutes of gut I/R. Control mice received normal saline infusion at 1 mL/h for 60 minutes during ischemia, whereas the ARG group was given 1% ARG hydrochloride solution. In Exp. 1, survival was observed for 72 hours (n = 35). In Exp. 2, blood perfusion and oxygen tension of the small intestine were measured (n = 9). In Exp. 3, peripheral blood was obtained at 2 or 4 hours after reperfusion (n = 22). Reactive oxygen intermediate (ROI) production by myeloid cells with or without phorbol myristate acetate (PMA) stimulation and expression of CD11a and CD11b on myeloid cells were examined using flow cytometry.

RESULTS

Exp. 1: There was no significant difference in survival times (log rank test, p = .2). However, survival rates at 12 hours were 72% (13/18) for the control group and 35% (6/17) for the ARG group (p < .05 Fisher). Exp. 2: ARG infusion significantly improved gut blood perfusion ratio during ischemia but had no effect on oxygen tension. Exp. 3: In the ARG group, ROI production with PMA and CD11b expression at 4 hours were higher than those at 2 hours, whereas there were no significant changes in the control mice.

CONCLUSIONS

ARG infusion improves intestinal blood perfusion during ischemia but primes and activates circulating myeloid cells excessively. Consequently, i.v. infusion of ARG during ischemia reduces survival rate.

Correlation of KIT and EGFR overexpression with invasive ductal breast carcinoma of the solid-tubular subtype, nuclear grade 3, and mesenchymal or myoepithelial differentiation

Although KIT and EGFR overexpressions are reported to occur in breast cancer, their pathological significance is still unclear. We examined KIT, EGFR, and c-erbB-2 overexpressions immunohistochemically in 150 cases of surgically resected breast cancer and their correlation with the histological type and grade and mesenchymal and/or myoepithelial immunophenotype of primary tumors. To facilitate the analysis, we constructed a tissue microarray comprising 2-mm diameter tissues cored from the representative tissue block of each tumor. KIT, EGFR, and c-erbB-2 overexpressions were detected in 15 (10%), 12 (8%), and 23 (15%), respectively. The KIT was more frequent in the group comprising comedo-type ductal carcinoma in situ and invasive ductal carcinomas (IDCs) of the solid-tubular subtype than in the group of other histological types (P=0.027), and the EGFR was more frequent in IDCs of solid-tubular type than in other histological types (P <0.05). KIT and EGFR overexpressions were correlated with nuclear grade 3 (P=0.0095 and 0.0005) and tended to be concurrent (P=0.005). KIT overexpression was correlated with vimentin and S-100 expression (P=0.003 and P=0.005), and EGFR overexpression was correlated with S100 expression (P=0.0001). These correlations with grade and mesenchymal/myoepithelial markers were not observed for c-erbB-2 overexpression. KIT and EGFR appeared to be indicators of high-grade breast carcinoma groups that often contain the carcinomas with mesenchymal and/or myoepithelial differentiation, which are distinct from the group with c-erbB-2 overexpression.

Hemoperfusion with polymyxin B-immobilized fibers reduced the number of CD16+ CD14+ monocytes in patients with septic shock

BACKGROUND

CD16+ CD14+ monocytes dramatically increase in number in patients with severe infection. Hemoperfusion with PMX-F (direct hemoperfusion with polymyxin B immobilized fibers) has been reported to be a safe and effective treatment for patients with septic shock, although the molecular mechanism that accounts for its effectiveness is still unclear. The purpose of this study was to quantify the number of CD16+ CD14+ monocytes in patients with an intra-abdominal infection and to evaluate the effects of PMX-F treatment on clinical parameters and leukocyte surface antigen expression in these patients.

MATERIALS AND METHODS

Seventeen septic patients who had an intra-abdominal infection were enrolled in this study; 7 of these patients received PMX-F treatment. Peripheral blood samples were obtained immediately after admission, and were also collected from the above 7 patients before, during, and immediately after their PMX-F treatment. The expression of CD14, CD16, and Toll-like receptor (TLR)-4 on these patients' monocytes was evaluated using flow cytometry. In addition, lipopolysaccharide (LPS)-induced production of TNF-alpha and IL-1beta by these cells was measured by ELISA.

RESULTS

Monocytic expression of CD16 and TLR-4 was significantly greater in septic patients than in healthy controls, and their proportion of CD16+ CD14+ monocytes was similarly elevated. LPS-induced production of TNF-alpha and IL-1beta by peripheral blood mononuclear cells (PBMCs) of septic patients was significantly reduced compared to controls. Furthermore, there was a reduction in the proportion of CD16+ CD14+ monocytes during PMX-F treatment, and in the expression of TLR-4 on monocytes after PMX-F treatment.

CONCLUSIONS

These results showed that the number of peripheral blood CD16+ CD14+ monocytes and monocytic TLR-4 expression were markedly increased, and the production of pro-inflammatory cytokines in response to LPS significantly reduced in patients with sepsis. PMX-F treatment was found to be effective in reducing the number of CD16+ CD14+ monocytes and in decreasing the monocytic expression of TLR-4 in patients with septic shock.

Enhanced interferon-gamma production and bacterial clearance in the liver of splenectomized mice in the models of Escherichia coli injection or intestinal obstruction

Although several studies have reported that splenectomy increases susceptibility to bacterial infections, other reports have indicated that splenectomy does not induce such susceptibility. To clarify this discrepancy, we studied the effects of splenectomy in the models of lipopolysaccharide (LPS) or Escherichia coli challenge and intestinal obstruction, focusing on cytokine production and bacterial clearance in the liver. Using C57BL/6 mice at 4 weeks after splenectomy or a sham operation, either LPS or E. coli was injected or an intestinal obstruction was made to examine the mortality, serum cytokine levels, cytokine production of the liver mononuclear cells (MNCs), and bacterial clearance in the liver. As a result, no differences were observed in survival rates after LPS or E. coli challenge between the mice with and without splenectomy. However, in a model of intestinal obstruction, splenectomized mice survived significantly longer than the sham-operated mice. Liver MNCs from splenectomized mice produced a significantly larger amount of interferon-gamma compared with those from sham-operated mice. Furthermore, bacterial counts in the liver at 2 h after E. coli injection and at 24 h after intestinal obstruction were significantly decreased in splenectomized mice compared with sham-operated mice. In conclusion, splenectomy does not impair host defense against bacteria infection provided that recovery is sufficient to allow compensatory processes in the liver to occur.

[Advances in sentinel node biopsy for breast cancer]

SN biopsy (SNB) has evolved rapidly during the past decade and has now become a standard of surgical care for patients with breast cancer. The primary purpose of SNB is to minimize patient morbidity from axillary staging, but SNB also presents research opportunities to further understand the role of the sentinel node in the natural history of breast cancer. We have attempted to highlight several issues regarding SN and its biopsy in this review, including:(1) Investigation of the optimal particle size for radiotracers. The success of SNB is, in large part, attributed to the particle size of radiolabeled tracers. Electron microscopy demonstrated significant accumulation of the tracer (tin colloid) in harvested SN, of which particle sizes were in the range of 100-150 nm. Therefore, this appeared to be a suitable particle size for SN identification. (2) Invention of a new gamma probe. A cord-and boxless handheld gamma probe was invented, which was more sensitive to radioactivity and involved a background subtraction function based on defined criteria. (3) Characterization of the immunologic response against tumor antigens. Fluorescence-activated cell sorting (FACS) analyses were performed to determine the phenotypic characteristics of B cells and T cells in SN. They revealed an increase in B cells expressing co-stimulated molecules as antigen-presenting cells in SN, compared with non-SN. With respect to T cells, a heterogeneous pattern of naive and memory T cells (TCM) was demonstrated in SN, in contrast to homogeneous pattern with TCM in non-SN. These results may support the concept that B cells play a significant role in antigen presentation required for T cell activation. Studies are currently in progress to test these possibilities.

Optimal particle size of radiocolloid for sentinel node identification in breast cancer — Electron microscopic study and clinical comparison

BACKGROUND

Sentinel node (SN) biopsy using a radiotracer is easy to learn, reproducible, and performed by the majority of breast cancer surgeons. However, this technique raises the question: what is the optimal particle size of colloid?

METHODS

Patients were injected with conventional tin colloid (median particle diameter: 700 nm) and the predominant particle size of radiocolloid retained in the SN was measured using electron microscopy. This showed a narrow distribution of colloidal size (100-150 nm). Patients were then injected with modified tin colloid having a median particle size of 100 nm. A clinical comparison was performed between conventional particle size or reduced particle size tin colloid and the SN biopsy success rate, the number of SNs, and the colloidal uptake in SNs.

RESULTS

A total of 118 patients were injected with the conventional tin colloid (group I) and 124 patients with the smaller particle colloid (group II). The identification rate and the number of SN in both groups were almost equal, and the patients with low-uptake SNs were not significantly less in group I(p = 0.55). However, in the subgroup of patients 60 years of age or more, group II had significantly more SNs than group I(1.4 vs 1.9; p = 0.03) and low-uptake SNs were significantly less common than in group I(p = 0.02).

CONCLUSIONS

The improvement of colloidal uptake in SNs using the smaller particle size tin colloid was confirmed, and this impact was statistically significant in the older population.

Paradoxical effect of IL-18 therapy on the severe and mild Escherichia coli infections in burn-injured mice

OBJECTIVE

To investigate the effects of IL-18 therapy on severe and mild bacterial infection after burn injury.

SUMMARY BACKGROUND DATA

IL-18 therapy restores IFN-gamma production in immunosuppressive mice following burn injury and up-regulate host response to LPS and experimental bacterial peritonitis. On the other hand, the overproduction of IFN-gamma could induce an exaggerated inflammation. Therefore, in this study, we focus on the beneficial and deleterious effects of IL-18-induced IFN-gamma and investigate the behavior of IL-18 in infections.

METHODS

Burn injury was induced in C57BL/6 mice and then they were i.p. injected with IL-18 (0.2 microg) on alternate days. After 1 week, severe and mild infections were made in mice by an Escherichia coli challenge (5 x 10 CFU and 1 x 10 CFU i.v., respectively).

RESULTS

IL-18 therapy decreased the mortality of burn-injured mice followed by a severe infection, whereas it unexpectedly increased the mortality of burned mice with a mild infection. The IL-18 therapy increased the number of liver mononuclear cells (MNCs), especially NK cells, and greatly up-regulated the impaired IFN-gamma production from the liver and spleen MNCs in mice with severe infection. Both the serum IFN-gamma concentrations recovered while the bacterial count in the liver decreased. In contrast, the serum IFN-gamma concentrations of the burned mice with mild infection did not decrease in comparison to the unburned mice, whereas IL-18 therapy greatly up-regulated the serum IFN-gamma levels in burned mice. However, IL-18 therapy significantly elevated the serum ALT and creatinine levels, thus suggesting that the mortality was induced by an exaggerated form of shock/multiorgan failure. These beneficial and deleterious effects of IL-18 therapy in mice with severe and mild infections, respectively, were all inhibited by anti-IFN-gamma Ab pretreatment.

CONCLUSION

IL-18 therapy can be a potent therapeutic tool against severe bacterial infection in immunocompromised hosts, but careful attention should also be paid to its adverse effects.

Utility of axillary ultrasound examination to select breast cancer patients suited for optimal sentinel node biopsy

BACKGROUND

Because sentinel node (SN) biopsy (SNB) is known to produce false-negative results, we examined the usefulness of axillary ultrasound (AUS) in selecting patients suitable for optimal SNB.

METHODS

A positive AUS finding (positive AUS) was defined as an echo pattern of a homogeneously hypoechoic SN without an echo-rich center, indicating massive to extensive nodal involvement. The identification of SNs was performed, and complete axillary dissection was carried out.

RESULTS

A total of 262 women were enrolled into the study (T1 disease = 94; T2 disease = 145; and T3 disease = 23). The incidence of positive AUS increased with increasing size of breast tumor (P <0.0001). The overall identification and false-negative rates were 88.2% and 10.8%, respectively. However, when limited to AUS-negative patients, SNs were identified in 205 of 208 patients (98.6%), and the false-negative rate was 1.7%.

CONCLUSIONS

AUS should be included in the preoperative procedure for the selection of breast cancer patients suitable for SNB.

Clinicopathologic and technical factors associated with the uptake of radiocolloid by sentinel nodes in patients with breast cancer

PURPOSE

Sentinel-node biopsy is becoming widely accepted in breast cancer treatment. Using the radioisotope technique, a lower risk of identification failure is related to the amount of radiocolloid in the sentinel nodes. The aim of this study was to identify the factors associated with the colloidal uptake of the sentinel nodes.

METHODS

Technetium-labeled colloid was injected peritumorally, with or without subdermal injection. According to the maximum radioactivity of the sentinel nodes, patients were divided into high (>/=100 counts/s) or low (<100 counts/s) uptake groups. The uptake was compared in relation to the clinicopathologic and technical features.

RESULTS

The sentinel node was identified in 183 of 186 patients (98.4%), with 60 and 123 patients in the low- and high-uptake groups (mean: 39 and 1003 counts/s), respectively. Multivariate analysis showed that an age of 65 years or older and a sentinel-node size of 8 mm or more were significantly more predominant in the low-uptake group.

CONCLUSION

Care must be taken when performing sentinel-node biopsy, especially for aged patients and for those with large sentinel nodes. The optimal technique should be determined on the basis of these results.

The increase of CD57+ T cells in the peripheral blood and their impaired immune functions in patients with advanced gastric cancer

In addition to natural killer (NK) cells, T cells expressing natural killer cell markers, CD56 or CD57 (NK type T cells), have been considered to play an important role in antitumor immunity. We examined the proportion of NK cell and NK type T cell subsets in the peripheral blood from patients with gastric cancer. The IFN-gamma production capacity and population of cytoplasmic perforin positive cells in peripheral blood mononuclear cells (PBMC) were evaluated. Peripheral blood samples were obtained from 56 patients with gastric cancer and 21 healthy volunteers. The proportion of CD56- CD57+ T cells (CD57+ T cells) was significantly higher in advanced gastric cancer patients than those in healthy volunteers and patients with early stage gastric cancer, whereas no correlation was observed between the proportion of CD56+ T cells or NK cells and tumor progression. Furthermore, a significant decrease of CD8+ CD57+ T cells was found in patients with advanced gastric cancer. The proportion of CD57+ T cells did not correlate with interferon-gamma (IFN-gamma) production from PBMC in gastric cancer patients, although a significant correlation was found between them in healthy volunteers. The proportion of perforin positive CD57+ T cells, especially CD8+ CD57+ T cells, in patients with gastric cancer was markedly lower than that in healthy volunteers. Collectively, although the proportion of CD57+ T cells in PBMC was found to increase with tumor progression, their function in antitumor immunity is impaired in patients with gastric cancer.

Characterization of bronchoalveolar lavage T cell subsets in sarcoidosis on the basis of CD57, CD4 and CD8

T cells expressing CD57 (a natural killer cell marker) with interferon-gamma (IFN-gamma) producing capacity increase under various conditions. CD57+ T cells are also present in the bronchoalveolar lavage fluid (BALF) of sarcoidosis, and several phenotypical and functional analyses of these cells have been reported. In the present study, BALF T cells obtained from 52 patients with sarcoidosis were classified further into CD4+CD57+ T cells, CD4+CD57- T cells, CD8+CD57+ T cells and CD8+CD57- T cells and their phenotypes and functional characteristics were assessed. Substantial proportions of these T cell subsets expressed natural killer cell markers CD161 and CD122. The biased expansion of Vbeta2 T cells was observed in both CD4+CD57+ T cells and CD4+CD57- T cells in BALF from most patients, while the expansion of other Vbeta T cells was also observed in some patients. Unexpectedly, the biased expansion of certain Vbeta T cells was also seen in either CD8+CD57+ T cells or CD8+CD57- T cells, while the expanded Vbeta T cells in CD8+ T cells differed substantially among individuals. BALF T cells showed a remarkably lower T cell receptor (TCR) intensity than that of peripheral blood T cells. Both CD8+ T cell subsets in BALF of sarcoidosis expressed the intracellular perforin/granzyme B, while all four subsets expressed intracellular IFN-gamma after in vitro activation, and CD4+ T cells, especially CD4+CD57+ T cells, expressed tumour necrosis factor-alpha. These findings indicate that CD57+ T cells as well as CD57- T cells in the BALF are phenotypically and functionally different from peripheral blood T cells and may play an important role in the Th1 dominant state and inflammation in pulmonary sarcoidosis.

[Role of polymorphonuclear neutrophils and macrophages in the prevention of postoperative infections]

Polymorphonuclear neutrophils (PMNs) and macrophages are recognized to serve as the first line of defense against bacterial contamination during the perioperative period. Chemoattractants produced by macrophages cause PMN accumulation at the inflammatory site. Proinflammatory cytokines released by macrophages increase adhesion molecule expression on the surface of endothelial cells. P- and E-selectins produce leukocyte rolling, whereas beta 2-integrin-ICAM-1 interaction causes firm adhesion of leukocytes to the endothelium, followed by migration to the interstitium. Thus appropriate activation of the inflammatory cascade leads to leukocyte migration to the infectious focus. In particular, during the first several hours after the onset of bacterial contamination, massive exudation of PMNs is generally observed. PMNs and macrophages phagocytose the bacteria via opsonization and kill them with oxygen products or proteolytic enzymes. Malnutrition and the lack of enteral nutrition are assumed to impair PMN-macrophage-dependent host defense by derangement of adhesion molecule expression and the cytokine milieu. Recently, sticky PMNs before surgery have been reported to increase infectious morbidity after surgery. In addition, augmented alpha 4-integrin-VCAM-1 interaction has been demonstrated during sepsis, which is possibly a mechanism for increased PMN adhesion and resultant organ injury. Further study is needed to clarify the mechanisms of the disturbed function of PMNs and macrophages under various conditions.

Glutamine infusion during ischemia is detrimental in a murine gut ischemia/reperfusion model

BACKGROUND

Gut ischemia/reperfusion (I/R) frequently occurs in clinical settings as a result of disproportionate splanchnic hypoperfusion during shock. Glutamine (GLN) supplementation of total parenteral nutrition (TPN) before gut I/R improves survival after gut I/R compared with standard TPN. However, it is unknown whether GLN treatment after the occurrence of the insult is beneficial or not. The aims of this study were to examine effects of GLN infusion during gut ischemia on survival, myeloid cell (neutrophils + monocytes) activation, and vascular permeability in organs.

METHODS

Male Institute of Cancer Research (ICR) mice were randomized to control and GLN groups. After IV cannulation, mice underwent 90 (experiments 1 and 2) or 60 (experiment 3) minutes of gut I/R. Control mice received normal saline infusion at 1 mL/h for 60 minutes during ischemia, whereas the GLN group was given 3% GLN solution. In experiment 1, survival rates were monitored for 72 hours (n = 25). In experiment 2, peripheral blood was obtained at 2 or 4 hours after reperfusion (n = 17). Reactive oxygen intermediate (ROI) production by myeloid cells was determined by flow cytometry using dihydrorhodamine 123 with or without phorbol myristate acetate stimulation. Expression of CD11a and CD11b on myeloid cells was also measured. Myeloperoxidase (MPO) activity in the lung was evaluated. In experiment 3, vascular permeability in organs was measured using Evans blue at 2 or 4 hours.

RESULTS

In experiment 1, survival time in the GLN group was significantly reduced compared with the control group (p = .02, log-rank test). The survival rates were 92% (12/13) and 42% (5/12) for the control and GLN groups at 12 hours (p = .01) and 38% (5/13) and 0% (0/12) at 48 hours (p = .02), respectively. In experiment 2, ROI production was significantly higher in the GLN group than in the control group after PMA stimulation both at 2 and 4 hours. CD11b expression was significantly higher in the GLN group than in the control group at 4 hours. There was no difference in pulmonary MPO activity at either time point. In experiment 3, GLN infusion significantly increased hepatic vascular permeability compared with saline infusion at 4 hours.

CONCLUSIONS

GLN infusion during ischemia is detrimental for survival after gut I/R. A possible mechanism is excessive priming of myeloid cells caused by GLN infusion. Timing of GLN administration is critical for outcome after gut ischemic insult.

Functional and Vbeta repertoire characterization of human CD8+ T-cell subsets with natural killer cell markers, CD56+ CD57- T cells, CD56+ CD57+ T cells and CD56- CD57+ T cells

We investigated the individual CD8+ populations with natural killer (NK) cell markers (NK-type T cell); CD56 single positive (CD56)-T cells, CD56/CD57 double positive (DP)-T cells and CD57 single positive (CD57)-T cells in the peripheral blood. All NK-type T-cell populations expressed CD122 and intermediate levels of T-cell receptor (TCR; regular CD8+ T cells are CD122- and express high levels of TCR). The number of both DP-T cells and CD57-T cells, but not CD56-T cells, gradually increased with age. All NK-type T-cell populations produced larger amounts of interferon-gamma than did regular CD8+ T cells after stimulation with interleukin (IL)-2, IL-12 and IL-15. However, CD56-T cells and CD57-T cells but not DP-T cells showed a potent antitumour cytotoxity to NK-sensitive K562 cells, whereas only CD56-T cells showed a potent cytotoxity to NK-resistant Raji cells. Furthermore, although NK-type T cells produced large amounts of soluble Fas-ligands, their cytotoxic activities appeared to be mediated by the perforin/granzyme pathway. The oligoclonal or pauciclonal expansions of certain VbetaT cells were found in each NK-type T-cell population. The non-variant CDR3 region(s) for the TCRbeta chain(s) showed CD57-T cells and CD56-T cells to be derived from distinct origins, while the DP-T cell population consisted of a mixture of the clones seen in both CD56-T cells and CD57-T cells. Our results suggest that CD57-T cells and CD56-T cells are functionally and ontogenically different populations while DP-T cells appear to originate from both CD56-T cells and CD57-T cells.

CD57+ T cells augment IFN-gamma production in a one-way mixed lymphocyte reaction and their expansion after stem cell transplantation in paediatric patients

To clarify the immune response of CD57+ T cells (most of them are CD8+) in peripheral blood (PB) against alloantigens in order to elucidate the T helper 1 (Th 1) immune response, we assessed the role of CD57+ T cells in IFN-gamma (one of the representative Th 1 cytokines) production in a one-way mixed lymphocyte reaction (MLR). In this study, we showed that CD57+ T cells in responder cells were essential for effective IFN-gamma production in allogeneic MLR due partly to the augmentation of the alloresponse of regular T cells. Furthermore, IFN-gamma production in MLR correlated with the proportions of CD57+ T cells in PB regardless of the responders' age. We also showed that the extent of the expansion of CD57+ T cells in paediatric patients after haematopoietic stem cell transplantation (HSCT) was markedly lower than that in adult patients. In addition, CD57+ T cells purified and activated with a combination of cytokines showed a greater cytotoxicity than regular T cells against human umbilical vein endothelial cells. Because IFN-gamma production in one-way MLR is a useful predictor of graft-versus-host disease (GVHD), especially in the acute phase that occurs after allogeneic HSCT, our findings suggested that CD57+ T cells play a role in the development of GVHD and thus may explain the reason as to why a higher donor age is associated with an increased risk of developing GVHD while, in addition, the incidence of severe GVHD in paediatric patients is lower than that in adult patients.

IFN-gamma production from liver mononuclear cells of mice in burn injury as well as in postburn bacterial infection models and the therapeutic effect of IL-18

Hosts after severe burn injury are known to have a defect in the Th1 immune response and are susceptible to bacterial infections. We herein show that liver NK cells are potent IFN-gamma producers early after burn injury. However, when mice were injected with LPS 24 h after burn injury, IFN-gamma production from liver mononuclear cells (MNC; which we previously showed to be NK cells) was suppressed, and the serum IFN-gamma concentration did not increase, while serum IL-10 conversely increased compared with control mice. Interestingly, a single injection of IL-18 simultaneously with LPS greatly restored the serum IFN-gamma concentration in mice with burn injury and also increased IFN-gamma production from liver MNC. Nevertheless, a single IL-18 injection into mice simultaneously with LPS was no longer effective in the restoration of serum IFN-gamma and IFN-gamma production from the liver MNC at 7 days after burn injury, when mice were considered to be the most immunocompromised. However, IL-18 injections into mice on alternate days beginning 1 day after burn injury strongly up-regulated LPS-induced serum IFN-gamma levels and IFN-gamma production from liver and spleen MNC of mice 7 days after burn injury and down-regulated serum IL-10. Furthermore, similar IL-18 therapy up-regulated serum IFN-gamma levels in mice with experimental bacterial peritonitis 7 days after burn injury and greatly decreased mouse mortality. Thus, IL-18 therapy restores the Th1 response and may decrease the susceptibility to bacterial infection in mice with burn injury.

Clinically useful detection criteria for sentinel nodes in patients with breast cancer using a radioisotope technique

BACKGROUND

The radioisotope technique has been used to identify sentinel nodes in patients with breast cancer. However, quantitative analysis of the radioactivity for detecting the sentinel nodes was not previously examined. In this study, we considered a clinically useful criterion for detecting sentinel nodes by a detailed analysis of 312 sentinel nodes using the radioisotope technique.

PATIENTS AND METHODS

Patients with T1-2, N0 breast cancer were eligible for this study. The nodes with the highest radioactivity after injection of technetium-labeled tin colloids were identified as hot nodes. The radioactivities of the hot nodes and the background counts of the axillary basin were examined in order to establish new criteria for detecting the sentinel nodes.

RESULTS

Between May 1997 and December 2001, 312 hot nodes were detected in 183 of 186 patients (98.4%). Since the false-negative rate for metastasis in hot nodes was only 2.1% (1/48), they could serve as sentinel nodes to predict the nodal status. However, there was a wide distribution of the hot nodes and the background in terms of absolute counts and a criterion for the sentinel nodes could not be established in terms of the absolute counts. When we adopted the criterion of sentinel nodes with a >/=100 count ratio in relation to the background, only 169 hot nodes (54.3%) met our definition. When the criterion of a >or=10 count ratio was adopted, all hot nodes met our definition and all other nodes remained non-sentinel nodes.

CONCLUSION

The criterion for defining sentinel nodes in our method is a node with a >or=10 count ratio with respect to the background. It is recommended that an analysis based on such objective data should be investigated in order to provide surgeons with more accurate and clinically useful criteria for detecting sentinel nodes.

Activation of human T cells with NK cell markers by staphylococcal enterotoxin A via IL-12 but not via IL-18

We have reported recently that mouse liver NK cells and NK1 x 1+ T cells were activated by bacterial superantigens via the IL-12 production from Kupffer cells. In the present study, we examined the effect of staphyloccoccal enterotoxin A (SEA) on human T cells with NK cell markers, CD56 or CD57 (NK-type T cells). After stimulating peripheral blood mononuclear cells (PBMC) with SEA, PBMC produced a large amount of IFN- and acquired a potent antitumour cytotoxicity. The in vitro depletion of either CD56+ TCR NK cells, CD56+ T cells or 57+ T cells from PBMC significantly inhibited the IFN- production from PBMC. When purified NK-type T cells, NK cells and regular T cells were cultured with monocytes and SEA they all produced IFN-, while the IFN- amounts produced by both NK-type T cells were greater than those produced by NK cells. NK cells as well as CD56+ T cells showed cytotoxicity against NK-sensitive K562 cells, whereas both NK-type T cells showed a more potent cytotoxicity against NK-resistant Raji cells than did NK cells. The IFN- production from each population as well as from whole PBMC was greatly inhibited by anti-IL-12 antibody but not by anti-IL-18 antibody. The antitumour cytotoxicity of whole PBMC was also significantly inhibited by anti-IL-12 antibody while the SEA-induced proliferation of PBMC was not affected by anti-IL-12 antibody. Furthermore, SEA-activated NK-type T cells as well as NK cells showed cytotoxicities against vascular endothelial cells. Our findings suggest that human NK-type T cells are thus involved in bacterial superantigen-induced immune response.

The influence of interleukin-10 and interleukin-18 on interferon-gamma production by peritoneal exudate cells in patients with gastric carcinoma

Although the peritoneal cavity (PC) is the most common site of metastasis in gastric carcinoma, its immune status in patients with advanced cancer remains largely unknown. We investigated the relationship between clinical parameters and cytokine levels in the PC and also evaluated IFN-y production by peritoneal exudate cells (PEC), obtained during surgery from patients with stage III-IV gastric carcinoma. Although the IFN-gamma and IL-12 levels in the PC did not differ between stage III and stage IV cancer patients, the latter had higher levels of IL-10 and IL-18. Those patients with higher IFN-gamma levels experienced a significantly better survival-rate than those with lower IFN-gamma levels, whereas IL-18 (but not IL-10) levels were inversely-correlated with survivaL IFN-gamma levels increased in parallel with IL-18 levels in patients who survived more than two years, but this correlation did not apply to patients who died of disease within two years. In addition, anti-CD3-Ab or cytokine- stimulated PEC from patients with low IL-10 levels in their PC produced a significantly greater amount of IFN-gamma than PEC from patients with high PC IL-10 levels. In conclusion, a high level of IFN-y in the PC is an indicator of favorable outcome. Both IL-10 and IL-18 levels in the PC increased with tumor progression. Although the number of PEC capable of producing IFN-gamma increases with tumor progression, their ability to secrete IFN-gamma in response to IL-18 may be influenced by local IL-10 levels in the PC.

Effect of weight loss on T-cell receptor-mediated T-cell function in elite athletes

PURPOSE

Long-term intensive exercise by athletes may sometimes lead to a susceptibility to infections. In the present study, we examined the differences in immune function between amateur wrestlers experiencing weight loss (WL) and those without WL who underwent similar intensive exercise training.

METHODS

Eighteen elite amateur wrestlers who attended the Japanese national championship were classified into two groups. One group consisted of those with either slight or no WL (without WL) (<4%; mean, 1%) (N = 9), and the other group consisted of those who needed a significant WL (with WL) (> or = 4%; mean, 7%) (N = 9) during a 1-month period of intensive training. The leukocyte counts as well as the leukocyte subsets in the peripheral blood were examined. The proliferation and cytokine production in T lymphocytes in response to bacterial superantigens (staphylococcal enterotoxin B, streptococcal pyrogenic exotoxin A) and anti-CD3 antibody (Ab) were also examined.

RESULTS

The total leukocyte counts and leukocyte subsets did not differ substantially between the groups and were also not different from the findings before starting the intensive exercise training. Natural killer cells and T cells among the lymphocytes significantly increased in both groups, whereas the increase in each group was not different. Although the T-cell responses to bacterial superantigens were not different, the anti-CD3 Ab-stimulated proliferation and interferon-gamma production of lymphocytes from the wrestlers with WL were significantly lower than those of the wrestlers without WL. This hyporesponsiveness to CD3 stimulation recovered 2 months after the tournament when the wrestlers reverted to their normal weight.

CONCLUSION

Intensive exercise in athletes accompanied by a rapid WL was found to compromise the CD3/T-cell receptor-mediated T-cell function in athletes.

Preoperative serum interleukin-18 level as a postoperative prognostic marker in patients with gastric carcinoma

BACKGROUND

Interleukin-18 (IL-18), a recently described cytokine produced mainly by macrophages, stimulates interferon-gamma (IFN-gamma) production by natural killer cells and T cells. Although it has been reported that serum IL-18 levels are higher in patients with advanced tuberculosis and acute graft-versus-host disease compared with normal controls, the authors found no reports regarding serum IL-18 levels in patients with malignant solid tumors. The purpose of this study was to determine serum IL-18 levels and their clinical significance in patients with gastric carcinoma.

METHODS

Peripheral blood samples were obtained from 94 patients with gastric carcinoma who underwent curative surgery and from 50 healthy volunteers. The serum IL-18 level, the IFN-gamma, level, and the Helicobacter pylori (HP) serology status were determined in each sample with an enzyme-linked immunosorbent assay.

RESULTS

The mean serum IL-18 level for all patients was significantly higher compared with the mean level in healthy volunteers (P < 0.01). IFN-gamma titers were below the level of detection in all samples tested. When the patients were subdivided into groups, it was found that the serum IL-18 level in patients with Stage II and III disease was significantly higher compared with the level found in healthy volunteers (P < 0.01). The serum IL-18 level decreased after patients underwent surgical resection. However, there was no significant difference in the serum IL-18 level between healthy controls and patients with Stage I or IV disease. Patients with IL-18 levels >or= 310 pg/mL (i.e., equal to or greater than the mean levels +/- 1 standard deviation in the healthy volunteers) experienced a significantly lower survival rate compared with patients who had IL-18 levels < 310 pg/mL after undergoing surgery (P < 0.05) despite a lack of any discernible difference in clinicopathologic factors between the two groups. The serum IL-18 level was identified as an independent postoperative prognostic factor in multivariate survival analysis using a Cox proportional hazards model (hazard ratio, 4.89; P = 0.01). There was no significant correlation between HP serology status and serum IL-18 levels.

CONCLUSIONS

The preoperative serum IL-18 level may represent a significant postoperative prognostic determinant in patients with gastric carcinoma. Its function in the host immune system remains to be elucidated.

Sentinel lymph node identification for patients with breast cancer using large-size radiotracer particles: technetium-99m-labeled tin colloids produced excellent results

Sentinel lymph node (SLN) biopsies using radioactive tracers have been reported to detect the metastatic status of the axillary lymph nodes in breast cancer patients. However, the optimal radioactive tracer particle sizes remain to be determined. In this study, identification of SLNs with large radiolabeled tin colloid particles was evaluated. Seventy-five patients with T1-2, N0 breast cancer were enrolled. Two hours prior to surgery, 1 to 2.5 mL technetium-99m-labeled tin colloid particles were injected around the tumor under ultrasonographic guidance. Immediately before the operation, dye fluids were also injected around the tumor to increase the interstitial pressure. After axillary dissection, lymph nodes with x100 or more uptake of radioactivity than the mean of the other lymph nodes are considered to be SLN. All lymph nodes from the axillary dissections were pathologically investigated, and the characteristics of SLNs were evaluated. SLNs were clearly identified in 74 of 75 patients (98.7%). Of 37 patients without SLN metastasis, pathological investigation revealed no further involvement of the remaining non-SLNs. The SLNs tended to be larger in size, and more than 50% were located in the lower medial site of the axilla. This is the first study to show that SLNs could successfully be identified with radiolabeled tin colloid particles. When SLNs were negative for metastases, non-SLNs were always negative.