bluuebunny/crossref_metadata_2025 huggingface dataset:
Inflammatory pseudotumour (inflammatory myofibroblastic tumour) of the pancreas: a report of six cases associated with obliterative phlebitis
Authors: Wreesmann V , Van Eijck C H J , Naus D C W H , Van Velthuysen M‐L F , Jeekel J , Mooi W J
Published: March 2003

Aims:

To describe in detail an uncommon pancreatic condition, which generally presents with cholestasis and a mass lesion suspicious of malignancy, and which is characterized histologically by proliferation of fibrous tissue with associated moderate or marked inflammation, as well as obliterative phlebitis.

Methods and results:

Out of a consecutive series of 23 pancreaticoduodenectomy specimens which on histological evaluation were found to contain no malignant tumour, six cases characterized by the features mentioned above were identified and investigated further. Poor circumscription, firm consistence, histology of dense sclerosis with scattered round cell infiltrates and associated obliterative phlebitis and often perineural accentuation of inflammation were the distinguishing features. On the basis of available histoloigical evidence, the term inflammatory pseudotumour perhaps remains the term best suited to designate this entity, since it sums up its two most distinctive features. However, the possibility that this lesion is in fact a neoplastic process with reactive inflammation (inflammatory myofibroblastic tumour) cannot be ruled out on the basis of the histology, and remains a serious consideration in view of the proven neoplastic nature of lesions with very similar histology arising elsewhere in the body. Importantly, none of the pancreatic lesions reported here recurred or progressed (five informative cases, median follow‐up time 70 months).

Conclusions:

Inflammatory pseudotumour (inflammatory myofibroblastic tumour) of the pancreas may closely mimic pancreatic adenocarcinoma clinically and radiologically.
Evidence that neurones accumulating amyloid can undergo lysis to form amyloid plaques in Alzheimer's disease
Authors: D'Andrea M R , Nagele R G , Wang H‐Y , Peterson P A , Lee D H S
Published: March 2003

Aims:

Amyloid has recently been shown to accumulate intracellularly in the brains of patients with Alzheimer's disease (AD), yet amyloid plaques are generally thought to arise from gradual extracellular amyloid deposition. We have investigated the possibility of a link between these two apparently conflicting observations.

Methods and results:

Immunohistochemistry and digital image analysis was used to examine the detailed localization of β‐amyloid42 (Aβ42), a major component of amyloid plaques, in the entorhinal cortex and hippocampus of AD brains. Aβ42 first selectively accumulates in the perikaryon of pyramidal cells as discrete, granules that appear to be cathepsin D‐positive, suggesting that they may represent lysosomes or lysosome‐derived structures. AD brain regions abundantly populated with pyramidal neurones exhibiting excessive Aβ42 accumulations also contained evidence of neuronal lysis. Lysis of these Aβ42‐burdened neurones apparently resulted in a local, radial dispersion of their cytoplasmic contents, including Aβ42 and lysosomal enzymes, into the surrounding extracellular space. A nuclear remnant was found at the dense core of many amyloid plaques, strengthening the idea that each amyloid plaque represents the end product of a single neuronal cell lysis. The inverse relationship between the amyloid plaque density and pyramidal cell density in the AD brain regions also supports this possibility, as does the close correlation between plaque size and the size of local pyramidal cells.

Conclusions:

Our findings suggest that excessive intracellular accumulation of Aβ42‐positive material in pyramidal cells can result in cell lysis, and that cell lysis is an important source of amyloid plaques and neuronal loss in AD brains.
Use of a monoclonal antibody against Lafora bodies for the immunocytochemical study of ground‐glass inclusions in hepatocytes due to cyanamide
Authors: Hashimoto K , Hoshii Y , Takahashi M , Mitsuno S , Hanai N , Watanabe Y , Ishihara T
Published: March 2003

Use of a monoclonal antibody against Lafora bodies for the immunocytochemical study of ground‐glass inclusions in hepatocytes due to cyanamide

Aims: Ground‐glass inclusions (GGIs) in hepatocytes are known to be associated with cyanamide treatment in patients with alcohol dependency. The purpose of this study was to assess the reactivity of a monoclonal antibody (MAb) raised against polyglucosan and to detect early events in GGI formation.

Methods and results: Formalin‐fixed paraffin‐embedded liver tissues from four patients treated with cyanamide were used. Sections were stained with haematoxylin and eosin and periodic acid–Schiff with and without diastase digestion, and were immunohistochemically stained with the MAb. For electron microscopic study, routinely processed liver tissue from one patient was examined with conventional and immunoelectron microscopy with use of the MAb. All specimens from the four cyanamide‐treated patients contained GGIs in the cytoplasm of hepatocytes, and these GGIs reacted intensely with the MAb. Fully developed GGIs contained various organelles, whereas early ones consisted primarily of glycogen granules and dilated smooth endoplasmic reticulum. In immunoelectron microscopic preparations, gold particles were located within GGIs, and the immunolabelled organelles appeared to be glycogen granules.

Conclusions: This novel MAb is useful for the detection of GGIs caused by cyanamide. Our results support the idea that GGI formation may result from specific abnormalities in glucose metabolism.
Two relatively distinct patterns of ameloblastoma: an anti‐apoptotic proliferating site in the outer layer (periphery) and a pro‐apoptotic differentiating site in the inner layer (centre)
Authors: Sandra F , Nakamura N , Mitsuyasu T , Shiratsuchi Y , Ohishi M
Published: March 2003

Two relatively distinct patterns of ameloblastoma: an anti‐apoptotic proliferating site in the outer layer (periphery) and a pro‐apoptotic differentiating site in the inner layer (centre)

Aims: This study was performed to determine the apoptotic behaviour of ameloblastomas by analysing the role of bcl‐2 family proteins in ameloblastomas and the location of terminally apoptotic cells in the ameloblastoma epithelial tissues.

Methods and results: For immunohistochemistry, tissue sections of 32 patients were treated with an antigen‐retrieval method. Primary antibodies against the apoptosis‐related proteins, bcl‐2, bcl‐X, bax, and bak were applied. Besides immunohistochemistry, Western blotting and TUNEL were also performed. Most of the outer layer cells were predominantly stained by the bcl‐2 antibody, while most of the inner layer cells were stained by antibodies against the apoptosis‐modulating proteins, bax and bak. Among the bcl‐2 family, bcl‐2 was the most ubiquitously expressed protein in ameloblastomas, while bcl‐X was expressed in the greatest concentrations. The major bcl‐X protein was bcl‐XL. Some of the inner layer cells entered the terminal apoptotic stage, which were revealed by TUNEL. The acanthomatous areas over‐expressed the apoptosis‐modulating proteins, especially bak.

Conclusions: Ameloblastoma has much more apoptosis‐inhibiting protein than the apoptosis‐modulating protein. Ameloblastoma has two relatively distinct patterns, an anti‐apoptotic proliferating site in the outer layer (periphery) and a pro‐apoptotic differentiating site in the inner layer (centre). The acanthomatous area, which was stained strongly by bak antibody and contained numerous terminally apoptotic cells, was considered as the differentiated area.
Immunohistochemical staining for calretinin is useful in the diagnosis of ovarian sex cord–stromal tumours
Authors: McCluggage W G , Maxwell P
Published: March 2003

Immunohistochemical staining for calretinin is useful in the diagnosis of ovarian sex cord–stromal tumours

Aims: Ovarian sex cord–stromal tumours are a heterogeneous group of neoplasms which may be confused morphologically with a wide variety of tumours. Calretinin positivity has previously been demonstrated in a small number of ovarian sex cord–stromal tumours. The aim of this study was to investigate calretinin staining in a series of these tumours and their histological mimics in order to determine the value of calretinin staining in a diagnostic setting.

Methods and results: Seventy‐two neoplasms, including 37 ovarian sex cord–stromal tumours and 35 miscellaneous neoplasms which may enter into the differential diagnosis, were stained with a commercially available polyclonal antibody against calretinin. All sex cord–stromal tumours exhibited positivity except for a single fibrothecoma. In this group of tumours staining was generally diffuse and strong. Small numbers of the miscellaneous group of neoplasms exhibited positivity but this tended to be focal and weak, although this was not always the case. There was consistent strong positive staining of granulosa cells in follicular cysts and corpora lutea. There was also positive staining of luteinized stromal cells in two cases of ovarian stromal hyperplasia and hyperthecosis.

Conclusions: Calretinin is a sensitive immunohistochemical marker of ovarian sex cord–stromal tumours and may be useful in a diagnostic setting. However, the value is somewhat limited since occasional neoplasms which enter into the morphological differential diagnosis may be positive. Be that as it may, calretinin positivity may be of value in the diagnosis of an ovarian sex cord–stromal tumour and its differentiation from other neoplasms. In this regard, calretinin should always be used as part of a larger panel.
Value of mesothelial and epithelial antibodies in distinguishing diffuse peritoneal mesothelioma in females from serous papillary carcinoma of the ovary and peritoneum
Authors: Attanoos R L , Webb R , Dojcinov S D , Gibbs A R
Published: March 2003

Value of mesothelial and epithelial antibodies in distinguishing diffuse peritoneal mesothelioma in females from serous papillary carcinoma of the ovary and peritoneum

Aims: To evaluate the role of mesothelial markers (calretinin, thrombomodulin, cytokeratin 5/6, and CD44H) and carcinoma markers (polyclonal and monoclonal carcinoembryonic antigen, Leu‐M1, CA‐125 and Ber‐EP4) in distinguishing diffuse peritoneal malignant mesothelioma from primary serous papillary adenocarcinoma of the ovary and peritoneum.

Methods and results: Paraffin‐embedded formalin‐fixed blocks from 32 diffuse peritoneal mesotheliomas of epithelial subtype (all females), 20 serous papillary ovarian carcinomas and three primary peritoneal serous papillary carcinomas were studied. Calretinin and Ber‐EP4 appeared to be the best positive mesothelial and carcinoma marker, respectively. Nuclear calretinin expression was identified in 28 of 32 malignant mesotheliomas with no nuclear immunoreactivity in the cohorts of serous papillary ovarian and peritoneal carcinomas, thus yielding 88% sensitivity and 100% specificity. Ber‐EP4 showed 95% sensitivity and 91% specificity for serous papillary ovarian carcin‐ oma. Thrombomodulin, cytokeratin 5/6 and CD44H immunoreactivities were seen in 18 (56%), 17 (53%) and 15 (47%) of peritoneal mesotheliomas, respectively, and in six (30%), five (25%) and five (25%) of the ovarian tumours, respectively. None of the three primary peritoneal serous papillary carcinomas expressed calretinin, thrombomodulin, cytokeratin 5/6 or CD44H. Polyclonal and monoclonal CEA, and Leu‐M1 were expressed by two (10%), one (5%) and seven (35%) serous papillary ovarian carcinomas, respectively. None of the serous papillary peritoneal carcinomas expressed polyclonal CEA, monoclonal CEA or Leu‐M1. CA‐125 was positive in 19 (95%) and two (67%) ovarian and peritoneal carcinomas, respectively, and in eight (25%) peritoneal mesotheliomas.

Conclusions: Calretinin and Ber‐EP4 are useful discriminant markers in distinguishing peritoneal mesothelioma in women from serous papillary ovarian and peritoneal carcinoma. The other mesothelial markers (thrombomodulin, cytokeratin 5/6, and CD44H) and carcinoma markers (polyclonal and monoclonal CEA, and Leu‐M1) yielded a too low sensitivity for practical use.
Expression of epidermal growth factor receptor in head and neck cancers correlates with clinical progression: a multicentre immunohistochemical study in the Asia–Pacific region
Authors: Putti T C , To K F , Hsu H C , Chan A T C , Lai G M , Tse G , Lee Y S , Whang‐Peng J , Millward M , Lin L , Lin X , Lee C S
Published: March 2003

Expression of epidermal growth factor receptor in head and neck cancers correlates with clinical progression: a multicentre immunohistochemical study in the Asia–Pacific region

Aims:  With ongoing efforts to target the epidermal growth factor receptor (EGFR)‐mediated tumour growth in the treatment of selected human malignancies, there is a need to determine the expression levels of EGFR and to evaluate its prognostic value in various malignancies in the Asia–Pacific region.

Methods and results:  A total of 172 patients with head and neck squamous cell carcinomas from Australia, Hong Kong, Singapore, and Taiwan were selected for EGFR detection. Immunohistochemical staining was performed to evaluate EGFR expression. EGFR expression was present in 88.4% (152/172) of all cases tested. Specifically, EGFR expression was found in 91.3% (42/46), 84.6% (22/26), 84.1% (37/44), 96.0% (24/25), and 87.1% (27/31) cases of head and neck squamous cell carcinomas from the oral cavity, oropharynx, nasopharynx, hypopharynx, and larynx, respectively. The results demonstrate a stronger EGFR expression in T4 tumours (P=0.017) and later clinical stages (P=0.016). No significant correlation was seen with risk factors, primary tumour site and ethnicity.

Conclusions:  The majority of head and neck squamous cell carcinomas express EGFR, indicating the importance of studying the efficacy of anti‐cancer therapy through this pathway. The results also show similar rates of receptor expression in head and neck squamous cell carcinoma patients from our region compared with other parts of the world.
Non‐HTLV‐1‐associated primary gastric T‐cell lymphomas show cytotoxic activity: clinicopathological, immunohistochemical characteristics and TIA‐1 expression in 31 cases
Authors: Hatano B , Ohshima K , Katoh A , Kanda M , Kawasaki C , Tsuchiya T , Shimazaki K , Haraoka S , Sugihara M , Suzumiya J , Kikuchi M
Published: March 2003

Aims:  Most primary gastrointestinal lymphomas are of B‐cell origin and T‐cell origin is very rare. Recent studies have suggested that human T‐cell lymphotrophic virus type 1 (HTLV‐1) may be involved in the development of primary gastric T‐cell lymphoma. We analysed 31 patients with primary gastric T‐cell lymphoma in south‐west Japan, an area endemic for HTLV‐1, and determined their phenotypes, genotypes, and HTLV‐1 status.

Methods and results:  Here we present 31 cases of primary gastric T‐cell lymphoma in a HTLV‐1‐endemic area in Japan and analyse the clinical status, histology, phenotype and virus status. The median age at onset of primary gastric T‐cell lymphoma was 57 years with a gender ratio of M:F = 1.58:1. Six of the 31 primary gastric T‐cell lymphoma cases had HTLV‐1 proviral DNA (five males, one female), nine of the 31 cases were positive for anti‐adult T cell leukaemia antibody, without examination of HTLV‐1 proviral DNA (five males, four females), eight were non‐HTLV‐1‐associated primary gastric T‐cell lymphoma (four males, four females) and the other eight cases were unknown. Primary gastric T‐cell lymphoma usually presented as a large ulcerated tumour at the corpus to the antrum and histologically consisted of anaplastic large cell type (n = 2), pleomorphic large cell type (n = 3), pleomorphic medium and large cell type (n = 14), pleomorphic medium cell type (n = 11), and angioimmunoblastic T‐cell lymphoma type (n = 1). There were no clear macroscopic and microscopic differences between HTLV‐1‐associated and non‐HTLV‐1‐associated primary gastric T‐cell lymphoma. Most patients died within 2 years of diagnosis, and both types of primary gastric T‐cell lymphoma (with and without HTLV‐1) were associated with poor prognosis. Cytotoxic marker analysis showed that HTLV‐1‐associated lymphomas were negative for TIA‐1, while non‐HTLV‐1‐associated lymphomas were positive for TIA‐1.

Conclusions:  Our results suggest that in HTLV‐1‐endemic areas, patients with HTLV‐1‐associated primary gastric T‐cell lymphoma should be managed carefully and that TIA‐1 seems to be useful for identifying the aetiology of this lesion.
Analysis of cytokine production and Vβ T‐cell receptor subsets in irradiated recipients receiving portal or peripheral venous reconstitution with allogeneic bone marrow cells, with or without additional anti‐cytokine monoclonal antibodies
Authors: GORCZYNSKI  , CHEN  , ZENG  , GORCZYNSKI  , TERZIOGLU
Published: March 2003

Irradiated (800 rads) AKR mice received intravenous (i.v.) reconstitution with a mixture of B10.BR T‐depleted bone marrow cells and spleen cells. Only in groups of mice treated additionally with i.v. cyclophosphamide (Cy; 150 mg/kg), 24 hr before transplantation, was long‐term (>60% at 50 days) survival seen. In mice receiving only irradiation all animals died by 30 days post‐transplantation. Histological changes consistent with graft‐versus‐host disease (GVHD) were seen in the liver of reconstituted mice at 30 days, along with an organ‐specific increase in Vβ3 T‐cell receptor‐positive (TCR+) cells. No such increase in Vβ3 TCR+ cells was seen in the spleen from the same mice. These data are consistent with a tissue antigen‐driven expansion of Vβ3 TCR+ cells associated with GVHD in the liver in this model. When we analysed cytokine production in vitro from CD3+ cells restimulated with ‘host’ (AKR) antigen‐presenting cells (APC), we found a transition in cytokine production from preferential synthesis of type‐1 cytokines [interleukin‐2 (IL‐2) and interferon‐γ (IFN‐γ)] at early times (day 15) post‐reconsitution to increased production of type‐2 cytokines [IL‐4, transforming growth factor‐β (TGF‐β) and IL‐10] at later times (day 30) post‐reconstitution in Cy‐treated recipients. Animals not receiving Cy did not show this ‘switch’ in cytokine production at later time points. We have observed a similar polarization in cytokine production, along with increased graft survival, in recipients of vascularized and non‐vascularized allografts after portal venous (p.v.), but not i.v., pretransplant donor‐specific immunization. We next studied AKR mice receiving 800 rads and subsequently reconsituted with B10.BR stem cells via the p.v. route. Again these mice showed prolonged survival (>50% at 50 days), with polarization to IL‐4, IL‐10 and TGF‐β on restimulation of CD3+ cells in vitro at 30 days post‐transplant and increased Vβ3 TCR+ cells in the liver. Infusion of anti‐IL‐12 monoclonal antibodies into irradiated mice receiving i.v. cell reconstitution produced a similar pattern of changes to those seen after p.v. reconstitution, while a combination of anti‐IL‐10 and anti‐TGF‐β monoclonal antibodies reversed the changes seen after p.v. reconstitution. These data are consistent with an important role for differential cytokine production in the regulation of GVHD following allogeneic bone marrow transplantation.
High‐affinity immunoglobulin E receptor (FcεRI)‐bearing eosinophils, mast cells, macrophages and Langerhans’ cells in allergen‐induced late‐phase cutaneous reactions in atopic subjects
Authors: YING  , BARATA  , MENG  , GRANT*  , BARKANS  , DURHAM  , KAY
Published: March 2003

We have used in situ hybridization (ISH) and immunohistochemistry (IHC) to investigate the kinetics of the expression for FcεRI mRNA (α‐, β‐ and γ‐chains), the α‐chain protein product, as well as the phenotype of the mRNA‐ or protein‐positive cells in allergen‐induced late‐phase skin reactions in atopic subjects. Compared with diluent controls, there were significant increases in the total numbers of mRNA+ cells for the α‐, β‐and γ‐chains for FcεRI at all time‐points (6, 24 and 48 hr) after allergen challenge (P<0·01). By double IHC/ISH significant increases in α‐, β‐ and γ‐chain mRNA+ macrophages, eosinophils, mast cells and CD1a+ cells were also observed after allergen challenge (P<0·05). The distribution of FcεRI subunit (α‐, β‐, or γ‐chain) mRNA+ co‐localization was CD68+ macrophages (42–47%), EG2+ eosinophils (33–39%), tryptase+ mast cells (5–11%) and CD1a+ Langerhans’ cells (2–4%). Using single IHC, significant increases in the total number of FcεRI protein+ cells (P<0·01) were observed 24 and 48 hr after allergen challenge. Double IHC showed that the distribution of FcεRI+ cells was tryptase+ mast cells (33%), CD68+ macrophages (36%), EG2+ eosinophils (20%), CD1a+ Langerhans’ cells (4%) and unidentified cells (7%), at the 24‐hr allergen‐challenged sites. These observations suggest that the cutaneous late‐phase reaction in man is associated with up‐regulation of FcεRI on eosinophils, macrophages, mast cells and Langerhans’ cells.
Human monoclonal antibodies specific to hepatitis B virus generated in a human/mouse radiation chimera: the Trimera system
Authors: EREN  , LUBIN  , TERKIELTAUB  , BEN‐MOSHE  , ZAUBERMAN  , UHLMANN  , TZAHOR  , MOSS  , ILAN  , SHOUVAL  , GALUN  , DAUDI  , MARCUS  , REISNER  , DAGAN
Published: March 2003

An approach to develop fully human monoclonal antibodies in a human/mouse radiation chimera, the Trimera system, is described. In this system, functional human lymphocytes are engrafted in normal strains of mice which are rendered immuno‐incompetent by lethal total body irradiation followed by radioprotection with severe combined immunodeficient (SCID) mouse bone marrow. Following transplantation, human lymphocytes colonize murine lymphatic organs and secrete human immunoglobulins. We have established this system as a tool to develop fully human monoclonal antibodies, and applied it for the generation of monoclonal antibodies specific for hepatitis B virus surface antigen. A strong memory response to hepatitis B surface antigen was elicited in Trimera engrafted with lymphocytes from human donors positive for antibodies to hepatitis B surface antigen. The human specific antibody fraction in the Trimera was 102–103‐fold higher as compared with that found in the donors. Spleens were harvested from Trimera mice showing high specific‐antibody titres and cells were fused to a human–mouse heteromyeloma fusion partner. Several stable hybridoma clones were isolated and characterized. These hybridomas produce high‐affinity, IgG, anti‐hepatitis B surface antigen antibodies demonstrating the potential of the Trimera system for generating fully human monoclonal antibodies. The biological function and the neutralizing activity of these antibodies are currently being tested.
An increase in basal glucocorticoid concentration with age induces suppressor macrophages with high‐density FcγRII/III
Authors: KIZAKI  , OOKAWARA  , OH‐ISHI  , ITOH  , IWABUCHI  , ONOÉ  , DAY  , GOOD  , OHNO
Published: March 2003

Ageing is usually accompanied by a decline in immune and neuroendocrine functions. To elucidate the mechanisms underlying age‐related immunosuppression, the functions and surface phenotypes of peritoneal cells in the monocyte/macrophage lineage from old mice were investigated. The role of glucocorticoids (GC) in the immunomodulation was also examined. Proliferative responses of spleen cells from control mice stimulated with concanavalin A (Con A) were significantly suppressed by adding peritoneal exudate cells from old mice. Flow cytometry analysis revealed that the proportion of MAC‐1+ cells with a high density of type II or type III receptor for the Fc portion of IgG (FcγRII/IIIbright cells) was increased markedly in the peritoneal exudate cells from old mice. The prominent suppressor activity for Con A responses of control spleen cells was found in the FcγRII/IIIbright cells, whereas MAC‐1+ cells with a low density of FcγRII/III (FcγRII/IIIdull cells) did not suppress the Con A responses. On the other hand, both the basal corticosterone concentrations in serum and the mRNA expression for GC receptor in peritoneal exudate cells increased significantly in old mice. Furthermore, the proportion of FcγRII/IIIbright cells in peritoneal exudate cells from old mice was normalized on administration of the GC antagonist RU 38 486 (mifepristone). These results suggest that the increase in basal corticosterone concentrations in old mice induces the generation of FcγRII/IIIbright suppressor cells, possibly leading to the immune‐suppressive state.
Kinetics of cytokine and NFAT gene expression in human interleukin‐2‐dependent T lymphoblasts stimulated via T‐cell receptor
Authors: SARENEVA  , MATIKAINEN  , VANHATALO  , MELÉN  , PELKONEN  , JULKUNEN
Published: March 2003

T cells respond to mitogenic or antigenic stimulation by proliferation and by turning on cytokine gene expression. Here we have analysed the kinetics and nature of cytokine production in human peripheral blood‐derived T lymphoblasts stimulated with anti‐CD3 antibodies or Lens culinaris lectin (LCL). T cells were purified from peripheral blood mononuclear cells (PBMC) and primarily activated with anti‐CD3 antibodies and cultured in the presence of interleukin‐2 (IL‐2). Anti‐CD3‐restimulated T cells (mainly CD8+) produced IL‐2, interferon‐γ (IFN‐γ) and tumour necrosis factor‐α (TNF‐α) and low levels of IL‐4 and IL‐10 transcripts and proteins. No IL‐6 gene expression was observed. In LCL‐stimulated cells the cytokine production pattern was very similar. Steady‐state mRNA levels of IL‐2, IL‐10 and IFN‐γ peaked at 3 hr after anti‐CD3 stimulation and declined rapidly thereafter. The kinetics of TNF‐α mRNA expression was faster, being at its peak level 1 hr after stimulation. Anti‐CD3‐stimulated IL‐2 gene expression was down‐regulated by protein synthesis inhibitor, whereas IL‐10, IFN‐γ and TNF‐α genes were readily induced independent of ongoing protein synthesis. T‐cell receptor stimulation also induced a very rapid expression of c‐jun, c‐fos and NFATc1 (NFATc) genes, the gene products of which are involved in cytokine gene expression. In conclusion, the cytokines synthesized by IL‐2‐dependent T cells were predominantly IL‐2, IFN‐γ and TNF‐α.
Peritoneal macrophages play an important role in eliminating human cells from severe combined immunodeficient mice transplanted with human peripheral blood lymphocytes
Authors: SHIBATA  , ASANO  , NOGUCHI  , NAITO  , OGURA  , DOI
Published: March 2003

To elucidate the mechanism of human cell elimination from severe combined immunodeficient (SCID) mice transplanted with human peripheral blood lymphocytes (hu‐PBL‐SCID mice), we explored the immunocytes in the peritoneal cavity in SCID mice where human PBL were transferred. When the phenotype of peritoneal exudate cells (PEC) was compared by flow cytometry among three congenic strains of SCID mice that differ in their acceptability for human PBL, the PEC in NOD‐scid mice, which exhibit the highest acceptability, contained the smallest number of F4/80lo/−Mac‐1+‐activated macrophages. Moreover, the proportions of natural killer cells in PEC of the three strains of SCID mice were not always correlated with the acceptability. These findings suggest the possibility that peritoneal macrophages eliminate human cells in hu‐PBL‐SCID mice. To verify this hypothesis, we evaluated the engraftment of human PBL into SCID mice that were treated with liposome‐encapsulated dichloromethylene diphosphonate, which selectively depletes macrophages by inducing apoptosis, or 8‐aminoguanidine hemisulphate salt, an inhibitor of inducible nitric oxide synthase of macrophages. As a result, both of these regimens improved engraftment of human PBL, indicating that peritoneal macrophages take part in human cell elimination in the peritoneal cavity of hu‐PBL‐SCID mice and that it is mediated, at least in part, by direct macrophage cytotoxicity utilizing nitric oxide.
Fetal natural killer cell function is suppressed
Authors: DOMINGUEZ  , MADRIGAL  , LAYRISSE  , COHEN
Published: March 2003

Previous studies have reported reduced natural killer (NK) cell activity in cord blood (CB) compared with adult blood mononuclear cell populations. Using a non‐radioactive killing assay, we have verified these findings suggesting that either the fetal NK cell function is suppressed or that these cells are functionally imm_ature. We have shown that CB NK cells are functional, since activating them with cytokines known to activate adult NK cells [interleukin‐2 (IL‐2), IL‐12 and IL‐15] increased activation. However, resting the cells, which enhanced adult NK cell activity (P<0·01), had no effect on fetal NK cells (P=0·2). These results suggested that fetal NK cells have the capacity to kill, but this is suppressed in vitro. This hypothesis was strengthened by our observation that eight of nine CB mononuclear cell populations had their NK activity restored by freeze–thawing, whereas four of five adult peripheral blood mononuclear cells had a reduced killing ability on freeze–thawing. Freeze–thawing removes a population of cells that suppresses CB NK cell function. To determine which was the case we performed extensive phenotypic analysis of the CB populations pre‐ and post‐freezing and found that the percentage of the CD3− CD56+ population within CB increased significantly (P<0·0005 by paired t‐test) with freezing, whereas freeze–thawing had no effect on this population within a normal adult peripheral blood mononuclear cell population. Our data suggest that within CB there is a population of cells, as yet undefined, which may be inhibiting NK cell function. This report therefore shows clear differences between NK cells within the adult periphery and in CB, and may lead to a better understanding of events occurring in vivo.
Lipopolysaccharide‐induced production of tumour necrosis factor and interleukin‐1 is differentially regulated at the receptor level: the role of CD14‐dependent and CD14‐independent pathways
Authors: NETEA M. G. , KULLBERG B. J. , VAN DER MEER J. W. M.
Published: March 2003

Cytokine production induced via CD14‐dependent and CD14‐independent pathways was investigated in mouse peritoneal macrophages incubated with lipopolysaccharide (LPS) or lipid A. Different LPS receptors appear to be responsible for production of tumour necrosis factor‐α (TNF‐α) and interleukin‐1α (IL‐1α) and IL‐1β. TNF‐α production is essentially CD14 dependent, both in the presence or absence of plasma. In the presence of plasma, endotoxin‐induced IL‐1 production is mediated by CD14‐dependent mechanisms, while in its absence both CD14‐dependent and CD14‐independent pathways are involved. Lipid A stimulates cytokine synthesis through both CD14‐dependent and CD14‐independent mechanisms, but its action is weaker than that of LPS, indicating that the polysaccharide moiety may be necessary for proper stimulation of mouse macrophages by endotoxin.
Role of mast cells and monoamines in the thrombocytopaenia and mortality elicited by tumour necrosis factor in mice
Authors: PIGUET  , VESIN  , GUO  , DONATI  , BARAZZONE
Published: March 2003

We explored the thrombocytopaenia elicited by the i.v. injection of mouse recombinant tumour necrosis factor (TNF) in mice. Injection of 10 μg of TNF led to a thrombocytopaenia (evident after 0·5 hr) which was caused by decreased platelet survival, as seen by the injection of labelled platelets. TNF‐induced thrombocytopaenia was not prevented by heparin, nor by depletion of either fibrinogen or C′. TNF‐induced thrombocytopaenia was markedly attenuated in mice treated with reserpine, an agent that depletes monoamines from mast cells and other cells, and in the mast‐cell‐deficient WWv mice. In vitro, TNF elicited a modest release of monoamine from peritoneal mast cells and from a mast cell line. When mice are injected with 3H‐serotonin (3H‐5HT) before TNF, TNF injection increased the plasma 3H‐5HT content 1 hr later, modifications absent in reserpine pretreated or mast‐cell‐deficient mice. 3H‐5HT content of the small intestine was markedly depleted in TNF‐injected mice, suggesting that this organ is the source of the plasma 3H‐5HT. Drop in body temperature and mortality induced by TNF were also attenuated in mast‐cell‐deficient, and in reserpine pretreated mice. These results indicate that TNF can induce a release of monoamines from mast cells, mainly from those of the small intestine, a process that contributes to TNF‐induced thrombocytopaenia and mortality.
Expression of NO‐synthase in cells of foreign‐body and BCG‐induced granulomata in mice: influence of L‐NAME on the evolution of the lesion
Authors: KREUGER  , TAMES  , MARIANO
Published: March 2003

The microbicidal activity of macrophages in an inflammatory milieu has been related to the production of a large number of cytokins and intermediary metabolites of oxygen and nitrogen among them, nitric oxide (NO). Considering that granulomatous inflammation is predominantly composed of macrophages and epithelioid cells, we decided to investigate the participation of NO in this peculiar type of inflammation. Two models were used: glass cover slip implantation into the subcutaneous tissue of mice and, the inoculation of live bacillus Calmette–Guérin (BCG) into the footpad of the animals. Using a histochemical method for the detection of NO synthase and of the concentration of citrulin metabolized by cells obtained from cover slips implanted on different time intervals or BCG‐activated peritoneal cells, it was possible to demonstrate that epithelioid cells do not produce NO. Cells from granuloma induced by BCG inoculation express NO synthase, with different degrees of reactivity with a higher intensity in the cytoplasm of cells located in the edge of the lesions. The expression of NO synthase in the cytoplasm of these cells decreases with the age of the lesions. It could also be demonstrated that in mice treated with l‐name, an inhibitor of NO metabolism, the lesions induced by BCG lost the granulomatous architecture, were necrotic, and had a significant increase in the bacillary load of the lesion. These data allow us to conclude that NO production by macrophages is a determining factor in the organization of the granulomatous lesion and that it also controls the bacterial load in BCG‐induced lesions in mice.
Oxidation of defined antigens allows protein unfolding and increases both proteolytic processing and exposes peptide epitopes which are recognized by specific T cells
Authors: CARRASCO‐MARÍN  , PAZ‐MIGUEL  , LÓPEZ‐MATO  , ALVAREZ‐DOMÍNGUEZ  , LEYVA‐COBIÁN
Published: March 2003

The participation of oxidative mechanisms in major histocompatibility complex (MHC) class II‐restricted antigen presentation was studied in vitro. In general, antigen processing is inhibited when peritoneal macrophages (MØ) are incubated with scavengers of reactive oxygen intermediates (ROI): mannitol (an ·OH scavenger), dimethylurea (DMTU, which reacts with H2O2 and HOCl) and NCO‐700 (an epoxysuccinic acid derivative which inhibits oxidant production by activated phagocytes and can scavenge reactive oxygen species in both NaOCl and hypoxanthine (XOD) systems). However, neither rotenone and antimycins (inhibitors of O−2 production at the NADH dehydrogenase and ubiquinone–cytochrome b regions, respectively) nor aminoguanidine (an inducible nitric oxide synthase inhibitor) impaired antigen presentation, thus indirectly discarding the participation of mitochondrial oxidation and reactive nitrogen intermediates (RNI) in antigen processing. ROI scavengers do not inhibit the MHC class II‐restricted presentation of antigens that need processing but have their disulphide bonds reduced. It can be shown that oxidation of protein antigens (either by chlorination or performic acid treatment) allow protein unfolding and enhance both processing and exposure of immunogenic epitopes to specific T cells.
Expression of Th1/Th2 cytokine mRNA in peritoneal exudative polymorphonuclear neutrophils and their effects on mononuclear cell Th1/Th2 cytokine production in MRL‐lpr/lpr mice
Authors: YU  , SUN  , TSAI  , TSAI  , TSAI  , HUANG  , HAN  , YU
Published: March 2003

Peritoneal exudative polymorphonuclear neutrophils (PEC‐PMN) and mononuclear cells (PEC‐MNC) were obtained from normal BALB/c and from autoimmune MRL‐lpr/lpr mice (lpr) with different disease severities. The spontaneous and mitogen‐stimulated expression of T‐helper lymphocyte type‐1 (Th1) [represented by interferon‐γ (IFN‐γ) and interleukin (IL‐2)] and T‐helper lymphocyte type‐2 (Th2) (represented by IL‐4 and IL‐10) cytokine mRNA in these cells was detected by reverse transcription‐polymerase chain reaction (RT–PCR). The production of these cytokines was measured by enzyme‐linked immunosorbent assay (ELISA). We found that the spontaneous expression of Th1/Th2 cytokine mRNA in PEC‐PMN from autoimmune mice was progressively increased in parallel with disease severity but was not changed by lipopolysaccharide (LPS) stimulation. By contrast, spontaneous expression of Th1/Th2 cytokine mRNA in PEC‐MNC from these mice was progressively decreased in parallel with disease severity but retained the responsiveness to phytohaemagglutinin (PHA) stimulation. To determine the effect of PEC‐PMN on Th1/Th2 cytokine production by PEC‐MNC, autologous PEC‐PMN and PEC‐MNC were co‐cultured at MNC:PMN ratios of 5:0, 4:1, 3:2, 2:3, 1:4 and 0:5 with PHA stimulation for 24 hr. The production of cytokines at each ratio was compared with the expected value, by calculation. We found that PEC‐PMN from autoimmune mice progressively suppressed the production of IL‐4, IL‐10 and IFN‐γ whereas the production of IL‐2 was enhanced by autologous MNC in parallel with disease severity. These results suggest that a reciprocal relationship exists in the expression of Th1/Th2 cytokine mRNA between PEC‐PMN and PEC‐MNC in lpr mice in parallel with disease severity. Autoimmune PEC‐PMN can exert significant modulatory effects on Th1/Th2 cytokine production by autologous MNC in stimulation.
Lymphocyte‐specific protein 1: a specific marker of human leucocytes
Authors: PULFORD  , JONES  , BANHAM  , HARALAMBIEVA  , MASON
Published: March 2003

While both murine and human homologues of the LSP1 gene (lymphocyte‐specific gene 1) and its protein products have been identified, studies on human LSP1 have been limited. The present report describes a detailed immunocytochemical study of the distribution and localization of human LSP1 in both normal and neoplastic cells and tissues. The specificity of the monoclonal anti‐LSP1 reagent was confirmed by expression cloning and transfection studies. The intracellular 60 000 MW LSP1 protein was found to be present in peripheral blood B cells, monocytes and granulocytes but absent in a subpopulation of circulating T cells (10–15% of CD3‐positive T cells). The presence of LSP1 protein in medullary thymocytes, but only in scattered cortical thymocytes, provided additional evidence for heterogeneity of expression in T cells. Novel observations also included the presence of LSP1 in plasma cells, dendritic cells and Langerhans’ cells. The leucocyte‐restricted distribution of LSP1 protein means that it may play an important role in haematopathology. LSP1 protein was detected in a wide range of leukaemias and lymphomas, particularly of B‐cell origin, and in tumour cells in classical Hodgkin’s disease. Of interest was the indication of a reciprocal relationship in the expression of LSP1 and ALK (anaplastic lymphoma kinase) proteins in patients with anaplastic large cell lymphoma. As the anti‐LSP1 reagent used in the present study recognizes a formalin‐resistant epitope it should be of considerable value in the diagnosis of routinely fixed material.
Interleukin‐4 and interferon‐γ synergistically increase secretory component gene expression, but are additive in stimulating secretory immunoglobulin A release by Calu‐3 airway epithelial cells
Authors: LOMAN  , JANSEN  , OUT  , LUTTER
Published: March 2003

Interleukin‐4 (IL‐4) and interferon‐γ (IFN‐γ) synergize to express polymeric immunoglobulin receptor (pIgR) but their combined effect, and that of IL‐4 alone, on secretory immunoglobulin A (sIgA) release is unknown. Recently, we have developed an airway epithelial cell model that allows assessment of the integrated effect of a stimulus on pIgR gene and protein expression and sIgA release. With this model we show here that IL‐4 and IFN‐γ dose‐dependently increased pIgR mRNA and protein expression, and sIgA release. IFN‐γ and IL‐4 induced similar maximal expression of pIgR, but IFN‐γ enhanced sIgA release more than IL‐4. When added together, IL‐4 and IFN‐γ synergistically increased pIgR mRNA and protein expression, but sIgA release was stimulated in an additive manner. Thus, IL‐4 and IFN‐γ may be implicated in the increase of sIgA levels as found in mucosal inflammatory diseases. In addition, our results indicate that transport and release of empty pIgR is subject to regulatory mechanisms different from those of pIgR with bound dimeric IgA.
CD69 is a stimulatory receptor for natural killer cell and its cytotoxic effect is blocked by CD94 inhibitory receptor
Authors: BORREGO  , ROBERTSON  , RITZ  , PEÑA  , SOLANA
Published: March 2003

CD69 is a differentiation antigen expressed shortly after activation on T lymphocytes and other cells of haematopoietic origin, including natural killer (NK) cells. The function of CD69 on T lymphocytes acting as a costimulatory molecule in proliferation and lymphokine secretion is well established. NK cells express CD69 after activation by different stimuli such as phorbol 12‐myristate 13‐acetate (PMA), interleukin (IL)‐2, IL‐12, interferon‐α (IFN‐α) or anti‐CD16 monoclonal antibodies (mAbs). However, although it has been shown that CD69 triggers NK‐cell‐mediated cytolytic activity, its effect on other NK‐cell functions has not been studied. Furthermore, the possible interaction of CD69 triggering with other C‐lectin type inhibitory receptors is not known. Thus, the objective of this work is to determine whether CD69‐mediated NK cytotoxicity can be regulated by CD94 inhibitory receptor and the role of CD69 on other NK‐cell functions different of cytotoxicity. The results show that CD69‐mediated NK cytotoxicity can be abrogated by CD94 stimulation in NK cells expressing the CD94 inhibitory form of the receptor, indicating that CD94 regulates the cytotoxic events initiated by a wide variety of NK activatory receptors. We also show that anti‐CD69 mAbs, not only triggered NK cytotoxicity, but also induce NK‐cell proliferation, CD25 and intracellular adhesion molecule‐1 (ICAM‐1) expression, TNF‐α production and Ca2+ mobilization in preactivated NK cells. These results suggest that CD69 plays a crucial role in NK‐cell function contributing to sustain NK‐cell activation, as it has been previously demonstrated in T cells.
Direct Ni2+ antigen formation on cultured human dendritic cells
Authors: VAN DEN BROEKE  , HEFFLER  , TENGVALL LINDER  , NILSSON  , KARLBERG  , SCHEYNIUS
Published: March 2003

The possible direct antigen formation of Ni2+ on antigen‐presenting cells (APCs) was studied with cultured human dendritic cells (DCs) obtained from 10 subjects contact allergic to Ni2+ and six non‐allergic control individuals. All contact allergic subjects showed a significantly increased peripheral blood mononuclear cell (PBMC) response in vitro to Ni2+. DCs were expanded from the plastic‐adherent cell fraction of PBMCs by culturing with granulocyte–macrophage colony‐stimulating factor (GM‐CSF) and interleukin‐4 (IL‐4) for 7 days to obtain immature DCs, and with the addition of monocyte‐conditioned medium for another 4 days, for DC maturation. The DCs were pulsed for 20 min with Ni2+ (50 μm) in protein‐free Hank’s balanced salt solution (HBSS) and added to freshly prepared autologous responder PBMCs. With five allergic subjects, immature DCs pulsed with Ni2+ demonstrated a significant capacity to activate Ni2+‐reactive lymphocytes. With the remaining five patients and the six controls no difference in lymphocyte proliferation was observed between Ni2+‐pulsed and non‐pulsed immature DCs. In contrast, with mature Ni2+‐pulsed DCs from both ‘positive responder’ (n=4) and ‘non‐responder’ (n=4) patients, there was a significantly stimulated PBMC proliferation, whereas with the controls (n=4) still no activation was observed. Our results indicate that direct formation of the antigenic determinant of Ni2+ on APCs is possible and that Ni2+ uptake and processing mechanisms may not play a major role. Differences in the ease of activation of Ni2+‐reactive lymphocytes are discussed in terms of a possible heterogeneity in the availability of Ni2+‐reactive groups presented on endogenous peptides bound in the antigen binding groove of human leucocyte antigen (HLA) class‐II molecules.
Specific inhibition of T‐cell adhesion to extracellular matrix and proinflammatory cytokine secretion by human recombinant galectin‐1
Authors: RABINOVICH  , ARIEL  , HERSHKOVIZ  , HIRABAYASHI  , KASAI  , LIDER
Published: March 2003

The migration of immune cells through the extracellular matrix (ECM) towards inflammatory sites is co‐ordinated by receptors recognizing ECM glycoproteins, chemokines and proinflammatory cytokines. In this context, galectins are secreted to the extracellular milieu, where they recognize poly‐N‐acetyllactosamine chains on major ECM glycoproteins, such as fibronectin and laminin. We investigated the possibility that galectin‐1 could modulate the adhesion of human T cells to ECM and ECM components. T cells were purified from human blood, activated with interleukin‐2 (IL‐2), labelled, and incubated further with intact immobilized ECM and ECM glycoproteins in the presence of increasing concentrations of human recombinant galectin‐1, or its more stable, related, C2‐S molecule obtained by site‐directed mutagenesis. The presence of galectin‐1 was shown to inhibit T‐cell adhesion to intact ECM, laminin and fibronectin, and to a lesser extent to collagen type IV, in a dose‐dependent manner. This effect was specifically blocked by anti‐galectin‐1 antibody and was dependent on the lectin’s carbohydrate‐binding properties. The inhibition of T‐cell adhesion by galectin‐1 correlates with the ability of this molecule to block the re‐organization of the activated cell’s actin cytoskeleton. Furthermore, tumour necrosis factor‐α (TNF‐α) and interferon‐γ (IFN‐γ) production was markedly reduced when IL‐2‐activated T cells were incubated with galectin‐1 or its mutant. This effect was prevented by β‐galactoside‐related sugars. The present study reveals an alternative inhibitory mechanism for explaining the suppressive properties of the galectin‐1 subfamily on inflammatory and autoimmune processes.