Profound analgesia is associated with a truncated peptide resulting from tissue specific alternative splicing of DRG CA8-204 regulated by an exon-level cis-eQTL

Carbonic anhydrase-8 (CA8) is an intracellular protein that functions as an allosteric inhibitor of inositol trisphosphate receptor-1 (ITPR1) critical to intracellular Ca⁺⁺ release, synaptic functions and neuronal excitability. We showed previously that murine nociception and analgesic responses are regulated by the expression of this gene in dorsal root ganglion (DRG) associated with a cis-eQTL. In this report, we identify an exon-level cis-eQTL (rs6471859) that regulates human DRG CA8 alternative splicing, producing a truncated 1,697bp transcript (e.g., CA8-204). Our functional genomic studies show the “G” allele at rs6471859 produces a cryptic 3’UTR splice site regulating expression of CA8-204. We developed constructs to study the expression and function of the naturally occurring CA8-204^G transcript (G allele at rs6471859), CA8-204^C (C allele at rs6471859 reversion mutation) and CA8-201 (full length transcript). CA8-204^G transcript expression occurred predominantly in non-neuronal cells (HEK293), while CA8-204^C expression was restricted to neuronal derived cells (NBL) in vitro. CA8-204^G produced a stable truncated transcript in HEK293 cells that was barely detectable in NBL cells. We also show CA8-204 produces a stable peptide that inhibits pITPR1 and Ca⁺⁺ release in HEK293 cells. These results imply homozygous G/G individuals at rs6471859, which are common in the general population, produce exclusively CA8-204^G that is barely detectable in neuronal cells. CA8 null mutations that greatly impact neuronal functions are associated with severe forms of spinal cerebellar ataxia, and our data suggest G/G homozygotes should display a similar phenotype. To address this question, we show in vivo using AAV8-FLAG-CA8-204^G and AAV8-V5-CA8-201 gene transfer delivered via intra-neural sciatic nerve injection (SN), that these viral constructs are able to transduce DRG cells and produce similar analgesic and anti-hyperalgesic responses to inflammatory pain. Immunohistochemistry (IHC) examinations of DRG tissues further show CA8-204^G peptide is expressed in advillin expressing neuronal cells, but to a lesser extent compared to glial cells. These findings explain why G/G homozygotes that exclusively produce this truncated functional peptide in DRG evade a severe phenotype. These genomic studies significantly advance the literature regarding structure-function studies on CA8-ITPR1 critical to calcium signaling pathways, synaptic functioning, neuronal excitability and analgesic responses.

Carbonic anhydrase-8 (CA8) inhibits IP3 binding to the inositol trisphosphate receptor-1(ITPR1), which regulates intracellular calcium signaling critical to neuronal functions. Recessive CA8-null mutants are associated with spinocerebellar ataxia and neurodegenerative disorders. We have previously demonstrated that nociception and analgesic responses are associated with a DRG cis-eQTL that regulates murine expression of this gene. This study focuses on a human DRG exon-level cis-eQTL (rs6471859) that regulates CA8-204 alternative splicing producing a truncated 1,697bp transcript. Herein, we demonstrate the “G” allele at rs6471859 produces a cryptic 3’UTR splice site regulating tissue-specific CA8-204 expression. In vitro studies show the “G” allele (CA8-204^G) produces a stable peptide that inhibits ITPR1 activation and Ca⁺⁺ release in non-neuronal cells, but not in neuronal cells. However, using AAV8 gene transfer in vivo we show CA8-204^G peptide is expressed in both glial and to a lesser extent in neuronal cells, producing profound analgesia and anti-hyperalgesia using inflammatory pain models, similar to the full length CA8-201 positive control. These data significantly extend our understanding of CA8 structure-function, demonstrating the truncated peptide may represent a novel therapeutic candidate.

Inference for multimarker adaptive enrichment trials

Identification of treatment selection biomarkers has become very important in cancer drug development. Adaptive enrichment designs have been developed for situations where a unique treatment selection biomarker is not apparent based on the mechanism of action of the drug. With such designs, the eligibility rules may be adaptively modified at interim analysis times to exclude patients who are unlikely to benefit from the test treatment.We consider a recently proposed, particularly flexible approach that permits development of model-based multifeature predictive classifiers as well as optimized cut-points for continuous biomarkers. A single significance test, including all randomized patients, is performed at the end of the trial of the strong null hypothesis that the expected outcome on the test treatment is no better than control for any of the subset populations of patients accrued in the K stages of the clinical trial. In this paper, we address 2 issues involving inference following an adaptive enrichment design as described above. The first is specification of the intended use population and estimation of treatment effect for that population following rejection of the strong null hypothesis. The second issue is defining conditions in which rejection of the strong null hypothesis implies rejection of the null hypothesis for the intended use population.

A Proof of Concept, Phase II Randomized European Trial, on the Efficacy of ALF-5755, a Novel Extracellular Matrix-Targeted Antioxidant in Patients with Acute Liver Diseases

Objective

No efficient medical treatment is available for severe acute hepatitis (SAH) except N-acetylcysteine for acetaminophen-induced acute liver failure. The human C-type lectin Reg3α, referred to as ALF-5755, improved survival in an animal model of acute liver failure and was well tolerated in a phase 1 trial in humans. We performed a phase 2a trial of ALF5755 in non-acetaminophen induced SAH.

Design

double-blind, randomized, placebo-controlled study. The primary end-point was the improvement in the coagulation protein synthesis assessed by the change of Prothrombin (PR) during the 72 hours following treatment initiation calculated as PRH0 minus PRH72 divided by 72 (PR slope H0H72). Intention to treat (ITT) and per-protocol (PP) analysis of the entire group and the Hepatitis B virus (HBV)/AIH (auto-immune hepatitis) sub-group were done separately.

Results

57 patients were included. Twenty-eight received ALF-5755, 29 the placebo. Etiologies were: Hepatitis A (n = 10), HBV (n = 13), AIH (n = 9), drug-induced (n = 8), other (n = 17). On the whole group, nor the PR slope H0H72 (0.18±0.31 vs 0.25±0.32), nor the transplant-free survival rate at day 21 (75 vs 86%) differed between groups. Conversely, in the HBV-AIH subgroup, in which ALF was more severe, PR slope H0-H72 was higher in the ALF-5755 arm, the difference being significant in PP analysis (0.048±0.066 vs -0.040±0.099, p = 0.04); the median length of hospitalization was lower in the ALF-5755 group (8 vs 14 days, p = 0.02).

Conclusion

ALF-5755 was not efficient in a ITT analysis performed on the whole sample; however it led to a significant, although moderate, clinical benefit in a PP analysis of the sub-group of patients with HBV or AIH related SAH. As HBV is the major cause of SAH in Asia and Africa and AIH a growing cause, this study emphasizes the need to pursuit the evaluation of this novel medical treatment of SAH.

Trial Registration

ClinicalTrials.gov NCT01318525

Recombinant Reg3α protein protects against experimental acute pancreatitis in mice

Regenerating gene 3α (Reg3α) protein is a trophic factor that stimulates cell and tissue proliferation, neogenesis and also acts against apoptosis and necrosis. In order to explore the potential roles of recombinant Reg3α (rReg3α), we produced a mature rReg3α polypeptide for direct administration in l-arginine (L-Arg) induced acute pancreatitis (AP) in mice. Our results showed that rReg3α stimulated cell proliferation through Erk1/2 and p38 phosphorylation and also cyclin D1 upregulation mediated by Akt/ATF-2 signaling. Moreover, rReg3α administration significantly reduced the pancreatic damage caused by L-Arg injection, as shown in histological examination and serum amylase, lipase and C-reactive protein (CRP) assays. Not only acinar cell necrosis but also apoptosis found in the pancreas of AP mice were alleviated by rReg3α. Finally, upregulated Bcl-2 and Bcl-xL and suppressed poly (ADP-ribose) synthetase/polymerase (PARP) levels were detected as being relevant to the mechanism of rReg3α protection. We therefore conclude that rReg3α acts as a protective polypeptide against AP in mice by enhancing Bcl-2 and Bcl-xL expressions and suppressing PARP level.

Galectin-3 Binding Protein Secreted by Breast Cancer Cells Inhibits Monocyte-Derived Fibrocyte Differentiation

To metastasize, tumor cells often need to migrate through a layer of collagen-containing scar tissue which encapsulates the tumor. A key component of scar tissue and fibrosing diseases is the monocyte-derived fibrocyte, a collagen-secreting profibrotic cell. To test the hypothesis that invasive tumor cells may block the formation of the fibrous sheath, we determined whether tumor cells secrete factors that inhibit monocyte-derived fibrocyte differentiation. We found that the human metastatic breast cancer cell line MDA-MB-231 secretes activity that inhibits human monocyte-derived fibrocyte differentiation, whereas less aggressive breast cancer cell lines secrete less of this activity. Purification indicated that Galectin-3 binding protein (LGALS3BP) is the active factor. Recombinant LGALS3BP inhibits monocyte-derived fibrocyte differentiation, and immunodepletion of LGALS3BP from MDA-MB 231 conditioned media removes the monocyte-derived fibrocyte differentiation-inhibiting activity. LGALS3BP inhibits the differentiation of monocyte-derived fibrocytes from wild-type mouse spleen cells, but not from SIGN-R1(-/-) mouse spleen cells, suggesting that CD209/SIGN-R1 is required for the LGALS3BP effect. Galectin-3 and galectin-1, binding partners of LGALS3BP, potentiate monocyte-derived fibrocyte differentiation. In breast cancer biopsies, increased levels of tumor cell-associated LGALS3BP were observed in regions of the tumor that were invading the surrounding stroma. These findings suggest LGALS3BP and galectin-3 as new targets to treat metastatic cancer and fibrosing diseases.

The effects of some tumor markers on human erythrocyte (HCA-I and HCA-II), bovine erythrocyte (BCA) and bovine lung (CA-IV) carbonic anhydrase enzyme activities in vitro

OBJECTIVE

The influence of prostatic acid phosphatase (PAP) and human chorionic gonadotropin (HCG), tumor markers have been investigated on human erythrocyte carbonic anhydrase (HCA-I and HCA-II) and bovine erythrocyte (BCA) and bovine lung carbonic anhydrase (CA-IV) in vitro.

BACKGROUND

Tumor markers are substances that can often be detected in higher-than-normal amounts in the blood, urine, or body tissues of some patients with certain types of cancer. Tumor markers are produced either by the tumor itself or by the body in response to the presence of cancer or certain benign (noncancerous) conditions. In addition to their role in cancer diagnosis, some tumor marker levels are measured before treatment to help doctors plan appropriate therapy.

RESULTS AND CONCLUSION

All of the tumor markers were determined to have inhibition effect, on human CA-I, CA-II, bovine erythrocyte CA (BCA) and bovine lung CA-IV isoenzymes. The effect of each tumor marker on CA was investigated by Wilbur-Andersen method modified by Rickly et al Inhibition effects of two different tumor markers on human CA-I, CA-II, bovine erythrocyte CA (BCA) and bovine lung CA-IV isoenzymes were determined by using the CO2-Hydratase method by plotting activity % vs (tumor markers). I50 values of tumor markers exhibiting inhibition effects were found by means of these graphs (Tab.1, Fig. 2, Ref. 20).

Translationally controlled tumor protein supplemented chitosan modified glass ionomer cement promotes osteoblast proliferation and function

The objective of this study was to evaluate the effect of translationally controlled tumor protein (TCTP) supplemented in a novel glass ionomer cement (BIO-GIC) on normal human osteoblasts (NHost cells). BIO-GIC was a glass ionomer cement (GIC) modified by adding chitosan and albumin to promote the release of TCTP. NHost cells were seeded on specimens of GIC, GIC+TCTP, BIO-GIC and BIO-GIC+TCTP. Cell proliferation was determined by BrdU assay. It was found that BIO-GIC+TCTP had significantly higher proliferation of cells than other specimens. Bone morphogenetic protein-2 (BMP-2) and osteopontin (OPN) gene expressions assessed by quantitative real time PCR and alkaline phosphatase (ALP) activity were used to determine cell differentiation. Bone cell function was investigated by calcium deposition using alizarin assay. Both BMP-2 and OPN gene expressions of cells cultured on specimens with added TCTP increased gradually up-regulation after day 1 and reached the highest on day 3 then down-regulation on day 7. The ALP activity of cells cultured on BIO-GIC+TCTP for 7 days and calcium content after 14 days were significantly higher than other groups. BIO-GIC+TCTP can promote osteoblast cells proliferation, differentiation and function.

TCTP is an androgen-regulated gene implicated in prostate cancer

TCTP has been implicated in a plethora of important cellular processes related to cell growth, cell cycle progression, malignant transformation and inhibition of apoptosis. In addition to these intracellular functions, TCTP has extracellular functions and plays an important role in immune cells. TCTP expression was previously shown to be deregulated in prostate cancer, but its function in prostate cancer cells is largely unknown. Here we show that TCTP expression is regulated by androgens in LNCaP prostate cancer cells in vitro as well as human prostate cancer xenografts in vivo. Knockdown of TCTP reduced colony formation and increased apoptosis in LNCaP cells, implicating it as an important factor for prostate cancer cell growth. Global gene expression profiling in TCTP knockdown LNCaP cells showed that several interferon regulated genes are regulated by TCTP, suggesting that it may have a role in regulating immune function in prostate cancer. In addition, recombinant TCTP treatment increased colony formation in LNCaP cells suggesting that secreted TCTP may function as a proliferative factor in prostate cancer. These results suggest that TCTP may have a role in prostate cancer development.

Mechanisms of action of islet neogenesis-associated protein: comparison of the full-length recombinant protein and a bioactive peptide

Islet neogenesis-associated protein (INGAP) was discovered in the partially duct-obstructed hamster pancreas as a factor inducing formation of new duct-associated islets. A bioactive portion of INGAP, INGAP(104-118) peptide (INGAP-P), has been shown to have neogenic and insulin-potentiating activity in numerous studies, including recent phase 2 clinical trials that demonstrated improved glucose homeostasis in both type 1 and type 2 diabetic patients. Aiming to improve INGAP-P efficacy and to understand its mechanism of action, we cloned the full-length protein (rINGAP) and compared the signaling events induced by the protein and the peptide in RIN-m5F cells that respond to INGAP with an increase in proliferation. Here, we show that, although both rINGAP and INGAP-P signal via the Ras/Raf/ERK pathway, rINGAP is at least 100 times more efficient on a molar basis than INGAP-P. For either ligand, ERK1/2 activation appears to be pertussis toxin sensitive, suggesting involvement of a G protein-coupled receptor(s). However, there are clear differences between the peptide and the protein in interactions with the cell surface and in the downstream signaling. We demonstrate that fluorescent-labeled rINGAP is characterized by clustering on the membrane and by slow internalization (≤5 h), whereas INGAP-P does not cluster and is internalized within minutes. Signaling by rINGAP appears to involve Src, in contrast to INGAP-P, which appears to activate Akt in addition to the Ras/Raf/ERK1/2 pathway. Thus our data suggest that interactions of INGAP with the cell surface are important to consider for further development of INGAP as a pharmacotherapy for diabetes.

Short-term effects of INGAP and Reg family peptides on the appearance of small β-cells clusters in non-diabetic mice

The Reg3 peptides INGAP-PP and human Reg3α/β (HIP) have been hypothesized to stimulate β-cell neogenesis in the pancreas. Administration of INGAP-PP has been shown to cause an increase in β-cell mass in multiple animal models, reverse streptozotocin (STZ) induced diabetes in mice and reduces HbA1c levels in type 2 diabetic humans. In this study, we have examined the ability of the INGAP-PP and HIP peptides to induce β-cell formation in vivo in normal mice through short-term administration of the peptides. We assessed the peptides ability to induce an increase in extra-islet insulin-positive cell clusters by looking at β-cell number by point counting morphometry on pancreata that had been randomized using the smooth fractionator principle in non-diabetic NMRI mice after short-term injections of the peptides (5 d). Five day continuous BrdU labeling was used to determine if the new β-cells were derived from replicating β-cells. Real time quantitative RT-PCR and immuno-histochemistry was used to analyze changes in pancreatic transcription factor expression. A 1.5- to 2-fold increase in the volume of small extra-islet insulin-positive clusters post 5 d treatment with INGAP-PP and HIP as compared with mice treated with a non-peptide control or scrambled peptide (p<0.05) (n = 7) was found. Five day continuous BrdU infusion during the 5 d period showed little or no incorporation in islets or small insulin clusters. Five days of treatment with INGAP-PP or HIP, showed a tendency toward increased levels of pancreatic progenitor markers such as Ngn3, Nkx6.1, Sox9 and Ins. These are the first studies to compare and indicate that the human Reg3 α/β (HIP) peptide has similar bioactivity in vivo as INGAP by causing formation of small β-cell clusters in extra-islet pancreatic tissue after only 5 d of treatment. Upregulation of pancreatic transcription factors may be part of the mechanism of action.

Translationally controlled tumor protein against apoptosis from 2-hydroxy-ethyl methacrylate in human dental pulp cells

2-Hydroxy-ethyl methacrylate (HEMA) is a major monomer released from resin-base dental restorative materials. HEMA is cytotoxic to pulp cells and leads to apoptosis. This study examined the effect of Translationally Controlled Tumor Protein (TCTP) against apoptosis from HEMA. TCTP from banana prawn (Penaeus merguiensis) was cloned and the protein was purified. It significantly increased the number of viable of HEMA-treated cells compared to HEMA-treated cells alone. Flow cytometry indicated the addition of TCTP at 10 μg/ml to 8 and 10 mM HEMA decreased the apoptotic cells from 20 to 10%. The proliferative property and anti-apoptotic activity against HEMA was concentration dependent. It was interesting that the added TCTP was not detected inside the cells and the native human TCTP was decreased after treated with HEMA and TCTP (20 μg/ml) + HEMA(10 mM) for 24 h. These results provided preliminary information, which may contribute to the development of less toxic dental materials.

Brown spider (Loxosceles genus) venom toxins: tools for biological purposes

Venomous animals use their venoms as tools for defense or predation. These venoms are complex mixtures, mainly enriched of proteic toxins or peptides with several, and different, biological activities. In general, spider venom is rich in biologically active molecules that are useful in experimental protocols for pharmacology, biochemistry, cell biology and immunology, as well as putative tools for biotechnology and industries. Spider venoms have recently garnered much attention from several research groups worldwide. Brown spider (Loxosceles genus) venom is enriched in low molecular mass proteins (5–40 kDa). Although their venom is produced in minute volumes (a few microliters), and contain only tens of micrograms of protein, the use of techniques based on molecular biology and proteomic analysis has afforded rational projects in the area and permitted the discovery and identification of a great number of novel toxins. The brown spider phospholipase-D family is undoubtedly the most investigated and characterized, although other important toxins, such as low molecular mass insecticidal peptides, metalloproteases and hyaluronidases have also been identified and featured in literature. The molecular pathways of the action of these toxins have been reported and brought new insights in the field of biotechnology. Herein, we shall see how recent reports describing discoveries in the area of brown spider venom have expanded biotechnological uses of molecules identified in these venoms, with special emphasis on the construction of a cDNA library for venom glands, transcriptome analysis, proteomic projects, recombinant expression of different proteic toxins, and finally structural descriptions based on crystallography of toxins.

Molecular targeting of glioblastoma: Drug discovery and therapies

Despite advances in treatment for glioblastoma multiforme (GBM), patient prognosis remains poor. Although there is growing evidence that molecular targeting could translate into better survival for GBM, current clinical data show limited impact on survival. Recent progress in GBM genomics implicate several activated pathways and numerous mutated genes. This molecular diversity can partially explain therapeutic resistance and several approaches have been postulated to target molecular changes. Furthermore, most drugs are unable to reach effective concentrations within the tumor owing to elevated intratumoral pressure, restrictive vasculature and other limiting factors. Here, we describe the preclinical and clinical developments in treatment strategies of GBM. We review the current clinical trials for GBM and discuss the challenges and future directions of targeted therapies.

Dynamic spectral-domain optical coherence elastography for tissue characterization

A dynamic spectral-domain optical coherence elastography (OCE) imaging technique is reported. In this technique, audio-frequency compressive vibrations are generated by a piezoelectric stack as external excitation, and strain rates in the sample are calculated and mapped quantitatively using phase-sensitive spectral-domain optical coherence tomography. At different driving frequencies, this technique provides contrast between sample regions with different mechanical properties, and thus is used to mechanically characterize tissue. We present images of a three-layer silicone tissue phantom and rat tumor tissue ex vivo, based on quantitative strain rate. Both acquisition speed and processing speed are improved dramatically compared with previous OCE imaging techniques. With high resolution, high acquisition speed, and the ability to characterize the mechanical properties of tissue, this OCE technique has potential use in non-destructive volumetric imaging and clinical applications.

Islet neogenesis-associated protein signaling in neonatal pancreatic rat islets: involvement of the cholinergic pathway

Islet neogenesis associated protein (INGAP) increases islet mass and insulin secretion in neonatal and adult rat islets. In the present study, we measured the short- and long-term effects of INGAP-PP (a pentadecapeptide having the 104-118 amino acid sequence of INGAP) upon islet protein expression and phosphorylation of components of the PI3K, MAPK and cholinergic pathways, and on insulin secretion. Short-term exposure of neonatal islets to INGAP-PP (90 s, 5, 15, and 30 min) significantly increased Akt1(-Ser473) and MAPK3/1(-Thr202/Tyr204) phosphorylation and INGAP-PP also acutely increased insulin secretion from islets perifused with 2 and 20 mM glucose. Islets cultured for 4 days in the presence of INGAP-PP showed an increased expression of Akt1, Frap1, and Mapk1 mRNAs as well as of the muscarinic M3 receptor subtype, and phospholipase C (PLC)-beta2 proteins. These islets also showed increased Akt1 and MAPK3/1 protein phosphorylation. Brief exposure of INGAP-PP-treated islets to carbachol (Cch) significantly increased P70S6K(-Thr389) and MAPK3/1 phosphorylation and these islets released more insulin when challenged with Cch that was prevented by the M3 receptor antagonist 4-DAMP, in a concentration-dependent manner. In conclusion, these data indicate that short- and long-term exposure to INGAP-PP significantly affects the expression and the phosphorylation of proteins involved in islet PI3K and MAPK signaling pathways. The observations of INGAPP-PP-stimulated up-regulation of cholinergic M3 receptors and PLC-beta2 proteins, enhanced P70S6K and MAPK3/1 phosphorylation and Cch-induced insulin secretion suggest a participation of the cholinergic pathway in INGAP-PP-mediated effects.

[Cloning and expression of the gene encoding rat IgE-dependent histamine-releasing factor and effect study on the recombinant protein]

AIM

To clone and express the gene encoding rat IgE-dependent histamine-releasing factor (rHRF) and to study the effect of recombinant rHRF to induce histamine release from rat sensitized mast cells.

METHODS

The complete coding region of rHRF was cloned and expressed in BL21 cells. The soluble recombinant rHRF was purified. Aliquots of the mast cells obtained from the lungs of OVA-immunized rats were separately stimulated by recombinant rHRF at different concentration. The released histamine was measured by the OPT spectrofluorometric procedure.

RESULTS

The cloned DNA fragment showed 97% nucleotide sequence identity and 95% deduced amino acid sequence identity with the mRNA of rat IgE-dependent histamine-releasing factor (or translationally controlled tumor protein) in GenBank. The recombinant rHRF showed a relative molecular mass of 24 000 in SDS-PAGE. The purified rHRF which was independent of the allergen induced histamine releasing from the sensitized mast cells in a dose-dependent manner.

CONCLUSION

The recombinant rHRF, which showed the effect of inducing histamine release from sensitized mast cells, would play an important role in the allergen diseases.

[Parasite-origin IgE-dependent histamine-releasing factors in inducing histamine release from sensitized mast cells]

OBJECTIVE

To obtain the recombinant IgE-dependent histamine-releasing factors of Schistosoma japonicum and Clonorchis sinensis (rSjHRF and rCsHRF) and to study the effect of recombinant HRFs to induce histamine release from sensitized rat mast cells.

METHODS

The complete coding regions of SjHRF and CsHRF were cloned separately, and the recombinant plasmids were respectively transformed and expressed in BL21 cells. The soluble recombinant rSjHRF and rCsHRF were purified. Aliquots of the mast cells obtained from the lungs of OVA-immunized rats were separately incubated with rSjHRF and rCsHRF and the released histamine was measured by the OPT spectrofluorometric procedure. The dose-dependent curves and the kinetics of histamine release induced by rSjHRF and rCsHRF were prepared.

RESULTS

The recombinant plasmids pET-30-rSjHRF and pET-30-rCsHRF were constructed successfully and the purified soluble recombinant proteins rSjHRF and rCsHRF were obtained by affinity chromatography. rSjHRF and rCsHRF induced histamine release from sensitized mast cells in a dose-dependent manner. At the concentration of 150 mg/L, the average rate of histamine release from sensitized mast cells induced by rSjHRF and rCsHRF were 49.78% and 32.63%, respectively. Histamine release increased with prolonged reaction time and the maximal release occurred at 35 min.

CONCLUSION

The recombinant parasite-originated IgE-dependent HRFs show an effect of inducing histamine release from sensitized mast cells, suggesting that this protein would play a role in type I hypersensitivity in hosts with parasitic infections.

[Effect of 14-3-3sigma on transcriptional activity of p73 gene]

BACKGROUND & OBJECTIVE

p53 gene is the main regulator of 14-3-3sigma. Activated p53 could induce the expression of 14-3-3sigma, while 14-3-3sigma stabilizes the expression of p53 and enhances its transcriptional activity. p63 and p73, the members of p53 family, also have some functions similar to p53. This study was to investigate the effect of 14-3-3sigma on the transcriptional activity of p73.

METHODS

Luciferase reporter assay, reverse transcription-polymerase chain reaction (RT-PCR), and Western blot were used to evaluate the effect of 14-3-3sigma on the transcriptional activity of p73 in p53-deficient human lung carcinoma cell line H1299. Colony formation test was used to evaluate the effect of 14-3-3sigma on the transcriptional activity of p73 in p53-mutant human breast cancer cell line MDA-MB-436.

RESULTS

The luciferase activities induced by bax and p21WAF1 promotors were significantly higher in p73-transfected H1299 cells than in control H1299 cells (P<0.01), and were further increased by the transfection of p73 (25 ng) and 14-3-3sigma (100, 200, and 400 ng) in a dose-dependent manner (P<0.01). The expression of bax and p21WAF1 were higher in p73-transfected H1299 cells than in control H1299 cells, and were significantly higher in p73-and 14-3-3sigma-transfected H1299 cells than in p73-transfected H1299 cells (P<0.01). The number of colonies was fewer in p73-transfected MDA-MB-436 cells than in control MDA-MB-436 cells, and the colonies were significantly smaller in p73-and 14-3-3sigma-transfected H1299 cells than in p73-transfected H1299 cells (P<0.01).

CONCLUSION

14-3-3sigma can enhance the transcriptional activity of p73 in a dose-dependent manner.

The role of Islet Neogenesis-Associated Protein (INGAP) in islet neogenesis

Islet Neogenesis-Associated Protein (INGAP) is a member of the Reg family of proteins implicated in various settings of endogenous pancreatic regeneration. The expression of INGAP and other RegIII proteins has also been linked temporally and spatially with the induction of islet neogenesis in animal models of disease and regeneration. Furthermore, administration of a peptide fragment of INGAP (INGAP peptide) has been demonstrated to reverse chemically induced diabetes as well as improve glycemic control and survival in an animal model of type 1 diabetes. Cultured human pancreatic tissue has also been shown to be responsive to INGAP peptide, producing islet-like structures with function, architecture and gene expression matching that of freshly isolated islets. Likewise, studies in normoglycemic animals show evidence of islet neogenesis. Finally, recent clinical studies suggest an effect of INGAP peptide to improve insulin production in type 1 diabetes and glycemic control in type 2 diabetes.

Intramuscular injection of islet neogenesis-associated protein peptide stimulates pancreatic islet neogenesis in healthy dogs

OBJECTIVES

Diabetes is a serious health problem. It has been proposed that islet neogenesis from pancreatic progenitor cells may restore insulin secretion in diabetic mammals. Islet neogenesis- associated protein (INGAP) stimulates islet neogenesis; therefore, we hypothesized that it would stimulate islet neogenesis in dogs.

METHODS

Forty nondiabetic beagle dogs were randomly divided into 4 groups. Group 1 received daily intramuscular injections of vehicle, whereas the other 3 groups received daily INGAP injections of 0.5, 1.5, or 10 mg/kg. After 30 days, pancreatic tissues were collected, and RNA and histological sections were analyzed.

RESULTS

In dogs treated with 1.5 mg/kg INGAP, there was a significant (P < 0.001) increase in the percentage of insulin-positive cells (P < 0.001) and insulin gene expression. There was a trend to increased insulin-positive cells and gene expression with treatments of 0.5 and 10 mg/kg peptide. Protein gene product 9.5-positive cells were increased with treatment.

CONCLUSIONS

These results indicate that INGAP stimulates cells in the pancreatic duct epithelium of healthy dogs (putative islet progenitor cells) to develop along a neuroendocrine pathway and form new islets in response to INGAP peptide. The INGAP might be an effective therapy for diabetes.

Symbiotic bacteria direct expression of an intestinal bactericidal lectin

The mammalian intestine harbors complex societies of beneficial bacteria that are maintained in the lumen with minimal penetration of mucosal surfaces. Microbial colonization of germ-free mice triggers epithelial expression of RegIIIgamma, a secreted C-type lectin. RegIIIgamma binds intestinal bacteria but lacks the complement recruitment domains present in other microbe-binding mammalian C-type lectins. We show that RegIIIgamma and its human counterpart, HIP/PAP, are directly antimicrobial proteins that bind their bacterial targets via interactions with peptidoglycan carbohydrate. We propose that these proteins represent an evolutionarily primitive form of lectin-mediated innate immunity, and that they reveal intestinal strategies for maintaining symbiotic host-microbial relationships.

Pancreatitis-associated protein I suppresses NF-kappa B activation through a JAK/STAT-mediated mechanism in epithelial cells

Pancreatitis-associated protein I (PAP I), also known as HIP, p23, or Reg2 protein, has recently been implicated in the endogenous regulation of inflammation. Although it was initially characterized as a protein that is overexpressed in acute pancreatitis, PAP I has also been associated with a number of inflammatory diseases, such as Crohn's disease. Knowing that PAP I and IL-10 responses share several features, we have used a pancreatic acinar cell line (AR42J) to assess the extent to which their expression is reciprocally regulated, and whether the JAK/STAT and NF-kappaB signaling pathways are involved in the suppression of inflammation mediated by PAP I. We observed that PAP I is induced in epithelial cells by IL-10 and by PAP I itself. In contrast, we found phosphorylation and nuclear translocation of STAT3 and induction of suppressor of cytokine signaling 3 in response to PAP I exposure. Finally, a JAK-specific inhibitor, tyrphostin AG490, markedly prevented PAP I-induced NF-kappaB inhibition, pointing to a cross-talk between JAK/STAT3 and NF-kappaB signaling pathways. Together, these findings indicate that PAP I inhibits the inflammatory response by blocking NF-kappaB activation through a STAT3-dependent mechanism. Important functional similarities to the anti-inflammatory cytokine IL-10 suggest that PAP I could play a role similar to that of IL-10 in epithelial cells.

Anti-inflammatory effects of pancreatitis associated protein in inflammatory bowel disease

BACKGROUND AND AIMS

Increased pancreatitis associated protein (PAP) mRNA has been reported in active inflammatory bowel disease (IBD). The aims of the current study were to characterise PAP production in IBD and the effects of PAP on inflammation.

PATIENTS AND METHODS

Serum PAP levels were determined in healthy controls (n = 29), inflammatory controls (n = 14), and IBD patients (n = 171). Ex vivo PAP secretion in intestinal tissue was measured in 56 IBD patients and 13 healthy controls. Cellular origin of PAP was determined by immunohistochemistry. The effects of exogenous PAP on nuclear factor kappaB (NFkappaB) activation, proinflammatory cytokine production, and endothelial adhesion molecule expression were also analysed ex vivo.

RESULTS

Patients with active IBD had increased serum PAP levels compared with controls, and these levels correlated with clinical and endoscopic disease severity. Ex vivo intestinal PAP synthesis was increased in active IBD and correlated with endoscopic and histological severity of inflammatory lesions. PAP localised to colonic Paneth cells. Incubation of mucosa from active Crohn's disease with PAP dose dependently reduced proinflammatory cytokines secretion. PAP prevented TNF-alpha induced NFkappaB activation in monocytic, epithelial, and endothelial cells and reduced proinflammatory cytokine mRNA levels and adhesion molecule expression.

CONCLUSIONS

PAP is synthesised by Paneth cells and is overexpressed in colonic tissue of active IBD. PAP inhibits NFkappaB activation and downregulates cytokine production and adhesion molecule expression in inflamed tissue. It may represent an anti-inflammatory mechanism and new therapeutic strategy in IBD.

HIP/PAP accelerates liver regeneration and protects against acetaminophen injury in mice

Human hepatocarcinoma-intestine-pancreas/pancreatic-associated protein HIP/PAP is a secreted C-type lectin belonging to group VII, according to Drickamer's classification. HIP/PAP is overexpressed in liver carcinoma; however, its functional role remains unclear. In this study, we demonstrate that HIP/PAP is a paracrine hepatic growth factor promoting both proliferation and viability of liver cells in vivo. First, a low number of implanted hepatocytes deriving from HIP/PAP-transgenic mice (<1:1,000) was sufficient to stimulate overall recipient severe combined immunodeficiency liver regeneration after partial hepatectomy. After a single injection of HIP/PAP protein, the percentages of bromodeoxyuridine-positive nuclei and mitosis were statistically higher than after saline injection, indicating that HIP/PAP acts as a paracrine mitogenic growth factor for the liver. Comparison of the early events posthepatectomy in control and transgenic mice indicated that HIP/PAP accelerates the accumulation/degradation of nuclear phospho-signal transducer activator transcription factor 3 and tumor necrosis factor alpha level, thus reflecting that HIP/PAP accelerates liver regeneration. Second, we showed that 80% of the HIP/PAP-transgenic mice versus 25% of the control mice were protected against lethal acetaminophen-induced fulminate hepatitis. A single injection of recombinant HIP/PAP induced a similar cytoprotective effect, demonstrating the antiapoptotic effect of HIP/PAP. Comparison of Cu/Zn superoxide dismutase activity and glutathione reductase-like effects in control and transgenic liver mice indicated that HIP/PAP exerts an antioxidant activity and prevents reactive oxygen species-induced mitochondrial damage by acetaminophen overdose. In conclusion, the present data offer new insights into the biological functions of C-type lectins. In addition, HIP/PAP is a promising candidate for the prevention and treatment of liver failure.

Stratifin-Induced Matrix Metalloproteinase-1 in Fibroblast Is Mediated by c-fos and p38 Mitogen-Activated Protein Kinase Activation

Previously, we have demonstrated that keratinocyte releasable stratifin, also known as 14-3-3 sigma protein, stimulates matrix metalloproteinase (MMP)-1 expression in dermal fibroblasts. In this study, we showed that stratifin induced fibroblast MMP-1 messenger ribonucleic acid (mRNA) and protein levels through p38 mitogen-activated protein kinase (MAPK). Our data indicated that treatment of dermal fibroblasts with stratifin resulted in rapid and transient upregulation of c-jun and c-fos mRNA levels. We also demonstrated that SB203580 (SB), a specific inhibitor of p38 MAPK activity, inhibited the activation of fibroblast MMP-1 mRNA expression by stratifin. Subsequently, western blot analysis revealed phosphorylation of p38 at 90 min after stratifin stimulation and this was decreased to approximately 50% of the maximum value by 120 min. Stratifin was demonstrated to increase MMP-1 protein levels starting at 4 h and reaching its peak at 12-24 h. Furthermore, SB significantly blocked the stratifin induction of MMP-1 protein levels (***p<0.005, n=3). Microarray analysis of stratifin-treated fibroblasts shows an increase in Elk4/Sap1 mRNA expression and this finding was confirmed by northern blot analysis. Our results indicate that stratifin markedly increase Elk4/Sap1 mRNA expression in a time-dependent fashion. In conclusion, stratifin stimulates fibroblast MMP-1 levels through the activation of c-fos and MAPK pathway.

Differentiated keratinocyte-releasable stratifin (14-3-3 sigma) stimulates MMP-1 expression in dermal fibroblasts

Through the use of a keratinocyte/fibroblast co-culture system, we have recently identified a potent keratinocyte-derived anti-fibrogenic factor (KDAF) for dermal fibroblasts. A sequential chromatography of the active fractions of keratinocyte-conditioned medium (KCM) and peptide mapping of the candidate proteins identified KDAF as being the keratinocyte-releasable 14-3-3 sigma (14-3-3sigma) protein, which is also known as stratifin. In this study, we hypothesize that differentiated, but not proliferating, keratinocytes are the primary source of releasable 14-3-3sigma in conditioned medium. To address this hypothesis, in a longitudinal study, keratinocyte differentiation was induced by growing these cells in a medium consisting of 50% keratinocyte serum-free medium (KSFM) and 50% Dulbecco's modified eagle's medium without any additives for up to 20 d. When KCM was collected every other day and added to fibroblasts, the level of matrix metalloproteinase (MMP)-1 mRNA expression was markedly increased in fibroblasts receiving KCM and this increase was even greater in cells receiving conditioned media collected at later time points relative to that of controls. The results of a western blot analysis further showed a marked increase in the expression of 14-3-3sigma protein in keratinocytes grown in test medium from day 4 to day 10. This finding was consistent with the levels of 14-3-3sigma mRNA expression in differentiated keratinocytes. In contrast to a very high level of 14-3-3sigma mRNA expression seen in keratinocytes, fibroblasts that are highly responsive to14-3-3sigma were unable to express this factor. Interestingly, the level of 14-3-3sigma mRNA expression was markedly higher in keratinocytes co-cultured with fibroblasts relative to that of mono-cultured keratinocytes. In conclusion, this study provides evidence that keratinocytes express a high level of 14-3-3sigma at the levels of mRNA and protein. But the releasable form of 14-3-3sigma protein was only found in conditioned medium derived from differentiated keratinocytes. Further, our recently purified recombinant 14-3-3sigma protein mimics the collagenase stimulatory effect of KCM in dermal fibroblasts.

Des-gamma-carboxy prothrombin is a potential autologous growth factor for hepatocellular carcinoma

Des-gamma-carboxyl prothrombin (DCP) is a well recognized tumor marker for hepatocellular carcinoma (HCC). In the present study, we demonstrate that DCP has a mitogenic effect on HCC cell lines. Purified DCP stimulated DNA synthesis of Hep3B and SK-Hep-1 cells in a dose-dependent manner. DCP was found to bind with cell surface receptor Met causing Met autophosphorylation and also to activate STAT3 signaling pathway through Janus kinase 1. Luciferase gene reporter analysis showed that DCP induced STAT3-related transcription. Small interfering RNAs against both STAT3 and Met abrogated DCP-induced cell proliferation. DCP did not affect the mitogen-activated protein kinase pathway, Myc signaling pathway, or phosphoinositide 3-kinase/Akt pathway. Based on these results, we believe that DCP acts as an autologous mitogen for HCC cell lines. The Met-Janus kinase 1-STAT3 signaling pathway may be a major signaling pathway for DCP-induced cell proliferation.

Insulin suppresses collagenase stimulatory effect of stratifin in dermal fibroblasts

A delicate balance between synthesis and degradation of extracellular matrix (ECM) by matrix metalloproteinases (MMPs) is an essential feature of tissue remodeling. We have recently demonstrated that keratinocyte releasable stratifin, also known as 14-3-3 sigma protein, plays a critical role in modulating collagenase (MMP-1) mRNA expression in human dermal fibroblasts. In this study, we further characterized the collagenase stimulatory effect of stratifin in dermal fibroblasts and evaluated its effect in the presence and absence of insulin. Our data indicate that stratifin increases the expression of collagenase mRNA more than 20-fold in dermal fibroblasts, grown in either Dulbecco's modified Eagle's medium (DMEM) plus 2% or 10% fetal bovine serum (FBS). Collagenase stimulatory effect of stratifin was completely blocked, when fibroblasts were cultured in test medium consisting of 50% keratinocyte serum-free medium (KSFM) and 50% DMEM. The collagenase suppressive effect of test medium was directly proportional to the volume of KSFM used. As this medium contained insulin, we then evaluated the collagenase stimulatory effect of stratifin in dermal fibroblasts in the presence and absence of insulin. The results revealed that stratifin significantly increased the expression of collagenase mRNA/18S (*p < 0.05, n = 3) ratio, while insulin significantly decreased the expression of collagenase mRNA/18S (*p < 0.05, n = 3) ratio. The insulin inhibitory effect on collagenase mRNA expression was time and dose dependent. The maximal inhibitory effect of insulin was seen at 36 h post treatment. In conclusion, stratifin stimulates the expression of collagenase mRNA expression in dermal fibroblasts and this effect is suppressed by insulin treatment.

Mucosal neuroendocrine cell abnormalities in patients with chronic constipation

OBJECTIVES

The aim of this study was to examine the distribution of neuroendocrine cells (NEC) in patients with chronic constipation (CC) as a means of establishing a relationship between pathology, symptomatology and treatment.

METHODS

Rectal biopsy specimens from 43 patients with CC (aged 17-82 years) and 20 age-matched normal controls were examined histopathologically using haematoxylin and eosin, and immunohistochemically using antibodies against chromogranin-A (Ch-A) and serotonin (5-HT) to detect NEC. The number of positive NEC per 70 crypts (CR) was counted and expressed as the ratio of NEC/CR. CC patients were divided into groups based on management, then compared using NEC/CR.

RESULTS

CC was managed conservatively in 29 patients (group A) and invasively in 14. Of these 14, 10 had normal histology (group B) and four had typical histopathological signs of intestinal neuronal dysplasia (IND; group C). All control specimens were unremarkable. In controls, NEC/CR was 0.94+/-0.33 for Ch-A and 0.32+/-0.08 for 5-HT. In group A, NEC/CR was 2.23+/-0.13 for Ch-A and 1.02+/-0.06 for 5-HT. In group B, it was 2.79+/-0.18 for Ch-A and 1.72+/-0.33 for 5-HT. In group C, it was 3.12+/-0.22 for Ch-A and 2.32+/-0.14 for 5-HT. The increase in Ch-A and 5-HT immunoreactive cells in groups B and C compared with controls was greater (p<0.01, p<0.05) than the increase seen in group A compared with controls (p<0.01, p<0.05).

CONCLUSIONS

These results demonstrate that increased numbers of NEC may play a role in the abnormal bowel function seen in CC, and may have some relationship with the development of giant submucosal ganglia in IND.

Translationally controlled tumor protein (TCTP) in the human prostate and prostate cancer cells: expression, distribution, and calcium binding activity

BACKGROUND

The translationally controlled tumor protein (TCTP) is an abundantly expressed protein found in a wide range of organisms from both the animal and plant kingdom. Initially described as a growth-related protein, knowledge of the biological actions of TCTP has been recently extended to include calcium binding, regulation of apoptosis, and microtubules stabilization. This report describes expression, distribution, and characterization of TCTP in human prostatic tissues and cell lines.

METHODS

Samples were analyzed by Western blot, RT-PCR, immunohistochemistry, and confocal microscopy. Calcium binding activity of the recombinant human prostatic protein was evaluated on a calcium overlay assay. A public SAGE database was analyzed to determine TCTP expression levels in normal and cancer tissues.

RESULTS

TCTP protein and mRNA were detected in all the specimens and cell lines analyzed. The protein was mainly expressed by the secretory luminal epithelial and basal layer cells. A significant amount of protein was present in the prostatic fluids. Subcellular distribution studies in prostate epithelial cells detected the protein in the cytoplasm in interphase and colocalized with tubulin during mitosis. The calcium binding capacity of prostatic TCTP was shown in vitro. Finally, SAGE data indicated TCTP as the calcium binding protein with the highest expression levels among those examined.

CONCLUSIONS

The results of the present study demonstrate, for the first time, the expression of TCTP in the human prostate and in prostate cancer cells, and suggest the involvement of the protein in key-processes such as apoptosis, cellular differentiation, and in the control of sperm functions.

Inhibition of cytokine gene transcription by the human recombinant histamine-releasing factor in human T lymphocytes

Human recombinant histamine-releasing factor (HrHRF) preincubation enhances the secretion of histamine, IL-4, and IL-13 from FcepsilonRI-stimulated human basophils. In GM-CSF-primed human eosinophils, HrHRF increases IL-8 production. Our recent experiments were designed to evaluate the effects of HrHRF on human T cell cytokine production. Purified T cells were preincubated with GST-tagged HrHRF, followed by stimulation with PMA and A23187 overnight. A partial inhibition of IL-2 and IL-13 production (30 and 75%, respectively) was detected compared with that in cells treated with PMA/A23187 alone. However, the production of IFN-gamma was similar in PMA/A23187 stimulated cells with or without HrHRF. The inhibition of cytokine protein production was dose dependent and specific to the HrHRF portion of GST-HrHRF. The inhibition was not due to endotoxin, since preincubation with polymyxin B and HrHRF gave similar results to that with HrHRF alone. The same pattern and specificity of cytokine regulation were replicated in the Jurkat T cell line as for primary T cells. The PMA/A23187-stimulated activity of a proximal promoter IL-13, IL-4, or IL-2 luciferase construct transfected into Jurkat cells was partially inhibited (60, 32, or 70%, respectively) upon GST-HrHRF preincubation, suggesting that HrHRF functions to inhibit cytokine production in Jurkat cells by preventing gene transcription. The inhibition of IL-2 promoter activation was specific to the HrHRF portion of GST-HrHRF. We conclude that HrHRF, in addition to functioning as a histamine-releasing factor, can differentially modulate the secretion of cytokines from human basophils, eosinophils, T cells, and murine B cells, suggesting that it may induce a complex array of responses at sites of allergic inflammation.

Hematopoietic cytokines as tumor markers

Stem cell factor (SCF), interleukin 3 (IL-3), granulocyte-macrophage-colony stimulating factor (GM-CSF), granulocyte-colony stimulating factor (G-CSF) and macrophage-colony stimulating factor (M-CSF) are members of a group of glycoproteins called hematopoietic cytokines (HCs). These cytokines regulate the growth and differentiation of hematopoietic progenitor cells and functionally activate mature neutrophils or macrophages. The effect of HCs is not limited to bone marrow cells. Some studies have shown that HCs can also stimulate the proliferation of non-hematopoietic cells. The receptors for HCs have been detected in cancer cell lines, and stimulation of HCs receptors induced proliferation of tumor cells. Moreover, some investigations have shown HC mRNA expression in these cell lines and recent studies have demonstrated that HCs can stimulate tumor progression. Several cells of malignant tumors have been observed to secrete large amounts of HCs and increased concentrations of HCs have been found in the sera of cancer patients. There are a number of situations in which the measurement of HCs may provide clinically useful information, particularly regarding prognosis and response to treatment. In this paper we discuss the results of studies that have examined the potential use of HCs as tumor markers.

The American dog tick, Dermacentor variabilis, encodes a functional histamine release factor homolog

We have identified a functional Dermacentor variabilis histamine release factor (DVHRF) homolog and shown that it is a secreted tick saliva protein. The 945 base pair (bp) full-length DVHRF cDNA has a 522 bp open reading frame that encodes a 20 kDa (173 amino acid) polypeptide. Sequence analysis showed that the two HRF signature amino acid sequences were conserved in DVHRF, indicating close structural similarity between DVHRF and other characterized HRF homologs. Northern and Western blotting analyses of partially fed and unfed ticks indicates that neither DVHRF transcriptional nor translational regulation were influenced by tick feeding activity. Like its counterparts from the mammalian system, tick DVHRF is expressed in various tissues, as assessed by both Northern and Western blotting analyses. Furthermore, an Escherichia coli-expressed recombinant DVHRF induced histamine secretion from a rat basophilic leukemic cell line in a dose-dependent manner. Extensive experimental evidence has shown that high levels of histamine at tick attachment sites impede the biological success of feeding ticks and, in response, ticks secrete histamine-binding proteins to minimize the adverse effects of histamine. Our results suggest the existence of a tick-derived multifaceted control mechanism for levels of histamine at tick feeding sites.

Regulation of multidrug resistance in cancer cells by hyaluronan

Multidrug resistance in cancer cells is often due to ATP-dependent efflux pumps, but is also linked to alterations in cell survival and apoptotic signaling pathways. We have found previously that perturbation of hyaluronan-tumor cell interaction by treatment with hyaluronan oligosaccharides suppresses the phosphoinositide 3-kinase/Akt cell survival signaling pathway in cancer cells and reduces tumor growth in vivo. Here we find that these oligomers suppress both the MAP kinase and phosphoinositide 3-kinase pathways in multidrug resistant tumor cells and sensitize these cells to a variety of chemotherapeutic drugs. On the other hand, increased hyaluronan production induces resistance in drug-sensitive tumor cells. Likewise, increased expression of emmprin, which is a glycoprotein that is present on the surface of most malignant cancer cells and that stimulates hyaluronan production, also induces increased resistance. Thus, perturbation of hyaluronan signaling may provide a dual therapeutic role, since it has intrinsic suppressive effects on tumor growth as well as sensitizing cancer cells to chemotherapeutic agents.

Lack of correlation between bronchial late allergic reaction to Dermatophagoides pteronyssinus and in vitro immunoglobulin E reactivity to histamine-releasing factor derived from mononuclear cells

BACKGROUND

Activity of immunoglobulin (Ig)E-dependent histamine-releasing factor (HRF) is dependent on the IgE molecules bound to the surface of basophils. Sera capable of passively sensitizing basophils to release histamine to HRF were designated IgE+ sera. IgE+ and HRF have been suggested to play a role in late allergic reaction (LAR).

OBJECTIVE

The working hypothesis was tested that IgE+ induces a LAR. Further, activity of HRF produced by mononuclear cells (HRF(mn)) was compared with that of recombinant HRF p23.

METHODS

Atopic patients (n = 82) were bronchially provoked with Dermatophagoides pteronyssinus extract and the change in forced expiratory volume in 1 second was monitored. A LAR was defined as forced expiratory volume in 1 second as percentage of baseline < 80% 4 to 10 hours after allergen challenge. The presence of HRF-responsive IgE in serum was determined using basophils sensitized in vitro by serum.

RESULTS

The presence of HRF(mn)-responsive IgE (IgE(mn+)) in serum was shown not be essential for a LAR: 63% of the patients with a LAR had no IgE(mn+) in their serum. Further, 71% of patients with IgE(mn+) did not have a LAR. HRF(mn) and recombinant HRF p23 were not equivalent in the bioassay: serum of 38 of 82 atopic patients sensitized basophils to release histamine to HRF(mn), whereas this was found with serum of 1 of 82 patients to HRF p23.

CONCLUSIONS

The results do not support the hypothesis that IgE(mn+) induces a LAR, but do not exclude the alternative hypothesis that HRFs are released during a LAR and contribute to asthma severity.

Response of the immune system of mammary tumor-bearing rats to cyclophosphamide and soluble low-molecular-mass tumor-associated antigens: the bone marrow and thymus

We showed in a previous study that soluble low-molecular-mass tumor-associated antigens (sTAA) promote the anti-tumor effect of the anticancer drug cyclophosphamide (CPA) on rat mammary carcinogenesis. In this report, we analyzed the possible mechanism underlying this phenomenon. Studies were performed on the bone marrow and thymus from the following groups of rats: i) control rats, ii) rats treated with sTAA, iii) rats treated with CPA, iv) rats treated with CPA and sTAA. The cellular content of the bone marrow and thymus (CD4+ and CD8+ lymphocytes) was analyzed morphometrically and immunohistochemically. In the bone marrow, CPA caused significant substitution of cellular components with fatty tissue whereas sTAA repaired this process. We found that CPA affects mainly the process of myelogenesis whereas sTAA protect the production of lymphocytes. In the thymus, CPA alone or in combination with sTAA repaired the inhibition effect of DMBA on synthesis of CD4+ and CD8+ thymocytes. sTAA further increased the amount of CD8+ T lymphocytes in the medulla of the thymus. Data in the literature as well as the findings presented here demonstrate that the tested treatment, including vaccination with sTAA, actively promotes the generation of the host's antitumor immune response.

Identification of Cripto-1 in human milk

Cripto-1 (CR-1) is an epidermal growth factor (EGF)-related peptide that plays an important role in normal mammary gland development. CR-1 is expressed in the growing terminal end buds in the virgin mouse mammary gland and its expression increases during pregnancy and lactation. Furthermore, CR-I is involved in the early stages of mouse mammary tumorigenesis and in the pathogenesis of human breast cancer. Since CR-1 is expressed in the mouse mammary gland at high levels during pregnancy and lactation, we have evaluated whether this protein is present in human milk. In the present study we demonstrate that a 28 kDa immunoreactive CR-1 protein is present in 24 human milk samples as assessed by western blot analysis and that by enzyme-linked immunosorbent assay the concentration of CR-1 ranges between 62 and 118 ng/ml. In addition, CR-1 that had been purified from human milk is able to stimulate the phosphorylation of mitogen activated protein kinase in nontransformed NMuMG mouse mammary epithelial cells. These results suggest that CR-1 in human milk may be important in regulating mammary gland development during pregnancy and lactation.

Autocrine interleukin-6 production and highly malignant multiple myeloma: relation with resistance to drug-induced apoptosis

In this study, flow cytometry was used to evaluate interleukin-6 (IL-6) production by bone marrow mononuclear cells from 47 patients with multiple myeloma (MM) in different clinical stages and 15 patients with monoclonal gammopathy of undetermined significance. In patients with MM, autocrine IL-6 production paralleled the clinical disease stage. The largest proportion of syndecan-1(+)/IL-6(+) cells was detected in patients with resistant relapse or primary refractory disease, suggesting that tumor progression involves expansion of myeloma cells producing IL-6. The authors assessed autocrine IL-6 production and in vitro proliferation and apoptosis of myeloma cells in 6 myeloma cell clones (MCCs) and in 2 myeloma cell lines, namely IM-9 and U-266-1970, which showed different sensitivities to the addition of exogenous IL-6. Autocrine IL-6 production was observed in IL-6-independent MCC-2, MCC-3, and MCC-5 cloned from patients with aggressive disease and in the IM-9 cell line. In contrast, IL-6-dependent MCC-1, MCC-4, and MCC-6 were syndecan-1(+) and IL-6(-). Blocking experiments with anti-IL-6 monoclonal antibody from clone AH65, which binds IL-6-IL-6Ralpha complexes, prevented cell proliferation of IL-6(+) MCCs. Flow cytometry evaluations after propidium iodide staining revealed different susceptibilities of MCCs to cell death. IL-6-producing MCCs showed minimal spontaneous and dexamethasone-induced apoptosis, whereas a regular amplitude of apoptosis occurred in the IL-6(-) MCCs. These data provide evidence that autocrine IL-6 reflects a highly malignant phenotype of myeloma cells. In fact, autocrine IL-6 production and deregulated apoptosis may induce expansion of selective IL-6(+) myeloma cells resistant to spontaneous and drug-induced cell death.

Microglial apoptosis induced by chromogranin A is mediated by mitochondrial depolarisation and the permeability transition but not by cytochrome c release

Chromogranin A is up-regulated in the senile plaques of Alzheimer's brain and is a novel activator of microglia, transforming them to a neurotoxic phenotype. Treatment of primary cultures of rat brain microglia or the murine N9 microglial cell line with chromogranin A resulted in nitric oxide production, which triggered microglial apoptosis. Exposure of microglia to chromogranin A resulted in a fall in mitochondrial membrane potential. Mitochondrial depolarisation and apoptosis were reduced significantly by cyclosporin A, but not by the calcineurin inhibitor FK506. Cytochrome c did not translocate from the mitochondria to the cytosol, but its expression became significantly enhanced within the mitochondria. Inhibition of caspase 1 attenuated chromogranin A-induced microglial apoptosis, but did not prevent mitochondrial depolarisation, indicating that apoptosis occurred downstream of mitochondrial depolarisation. Conversely, staurosporine-induced microglial apoptosis led to mitochondrial cytochrome c release, but not caspase 1 activation. Our findings provide insight into the pathways controlling activation-triggered microglial apoptosis and may point to routes for the modulation of microglial evoked neurotoxicity.

Tumor-associated hyaluronic acid: a new sensitive and specific urine marker for bladder cancer

Hyaluronic acid (HA), a glycosaminoglycan, is known to promote tumor cell adhesion and migration, and its small fragments stimulate angiogenesis. We compared levels of HA in the urine of normal individuals and patients with bladder cancer or other genitourinary conditions, using a sensitive ELISA-like assay. Among the 144 specimens analyzed, the urinary HA levels of bladder cancer patients with G1 (255 +/- 41.7 ng/mg), G2 (291.8 +/- 68.3 ng/mg) and G3 (428.4 +/- 67 ng/mg) tumors are 4-9-fold elevated as compared to those of normal individuals (44.7 +/- 6.2 ng/mg) and patients with other genitourinary conditions (69.5 +/- 6.8 ng/mg; P < 0.001). Urinary HA measurement by the ELISA-like assay shows a sensitivity of 91.9% and specificity of 92.8% to detect bladder cancer. Thus, urinary HA measurement is a simple, noninvasive yet highly sensitive and specific method for bladder cancer detection. The increase in urinary HA concentration is a direct correlate of the elevated tumor-associated HA levels, because the HA levels are also elevated (3-5-fold) in bladder tumor tissues (P < 0.001). The profiles of urinary HA species of normal individuals and bladder cancer patients are different. Although only the intermediate-size HA species are found in the urine of normal and low-grade bladder tumor patients, the urine of high-grade bladder cancer patients contains both the high molecular mass and the small angiogenic HA fragments. These urinary HA fragments stimulate a mitogenic response (2.4-fold) in primary human microvessel endothelial cells, suggesting that the small HA fragments may regulate tumor angiogenesis by modulating endothelial cell functions.

Role of steroid hormone and growth factor receptors and proto-oncogenes in the behavior of human mammary epithelial cancer cells in vitro

The cultivation of cells from primary breast cancers is very unpredictable. The majority of breast-cancer-derived cell lines are of metastatic origin. To define the characteristics of tumor cells which govern their ability to grow in vitro as primary cultures as well as continuous or established culture cell lineages, human mammary epithelial cancer (HMEC) cells from 18 cases of unselected primary breast cancer were propagated in culture. Propagation of HMEC cells in vitro as monolayers in primary culture was successful in 10 out of 18 (55.5%) cases, which showed continous proliferation of tumor cells only up to 6-8 passages before they reached senescence. An investigation of the effects of phenotypic expression of estrogen receptors (ER), the progesterone receptors, c-erbB-2 oncoprotein and epidermal growth factor receptors (EGFR) on the capacity of HMEC cells to grow in vitro as monolayers showed that expression of ER and EGFR is required for controlling tumor proliferative activity in vitro. Expression of ER protein made the growth of HMEC cells more difficult, while expression of EGFR protein made their growth in vitro easier. Phenotypic characteristics of floating HMEC cells were found to be different from those grown on cover slips as adherent cultures, suggesting a selective growth of HMEC cells of a specific phenotype in culture. Cultured HMEC cells in subsequent passages showed a decrease in their proliferative capacity, alterations in phenotypic characteristics and development of morphologic features of terminal differentiation, resulting in senescence.

Reversal of CAMAL-mediated alterations of normal and leukemic in vitro myelopoiesis using inhibitors of proteolytic activity

CAMAL (common antigen of myelogenous acute leukemia) is an antigenic preparation isolated in this laboratory from the bone marrow or peripheral blood leucocytes of persons with myeloid leukemias. Material from CAMAL preparations, which migrates in the range of 30 to 35 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE, P30-35 CAMAL), was shown to exert an inhibitory effect on in vitro colony formation by progenitor cells from normal healthy donors. The same preparations of P30-35 CAMAL, in contrast, exerted a stimulatory effect on in vitro colony formation by progenitor cells from patients with chronic myelogenous leukemia (CML). We now report that both the inhibitory effect on normal colony formation and the stimulatory effect on CML colony formation mediated by P30-35 CAMAL were blocked using phenyl methyl sulfonyl fluoride (PMSF), an inhibitor of the activity of serine proteases. Similarly, both the P30-35 CAMAL-mediated inhibitory effect on normal colony formation and the P30-35 CAMAL-mediated stimulatory effect on CML colony formation were blocked using the peptide ala-pro-phe-CMK, also an inhibitor of serine protease activity. These results suggest the involvement of proteolytic activity, either directly or indirectly, in the alterations of in vitro myelopoiesis exerted by P30-35 CAMAL.

[Effects of trophoblastic beta 1-glycoprotein (TBG) on the functional activity of different cell lines]

The effect of TBG on the functional activity of different cell lines, spontaneous and Con A induced proliferation of PBL was studied. If concentration of TBG is higher than 50 mu kg/ml it suppresses the proliferation in many used cell lines, except choriocarcinoma and cancer of uterus. The reliable increasing of spontaneous proliferation of PBL, Jurkat and K-562 cells may be observed if concentration is more lower (0.5-15 mu kg/ml). However proliferation of other cell lines corresponds to control level, and Con A induced proliferation of PBL is inhibited. The effect was more marked at 48, as compared to 24 hours of cell incubation with TBG.