bluuebunny/crossref_metadata_2025 huggingface dataset:
Safety and feasibility of acute percutaneous septal sinus shortening: First‐in‐human experience
Authors: Palacios Igor F. , Condado José A. , Brandi Sergio , Rodriguez Victor , Bosch Fernando , Silva Gaston , Low Reginald I. , Rogers Jason H.
Published: February 2007

Background:

Multiple percutaneous therapies for the treatment of functional and ischemic mitral regurgitation (FMR/IMR) are under development. We previously reported a novel percutaneous technique, the percutaneous septal sinus shortening [PS3] System™, which was effective in ameliorating FMR in an animal model. We herein report results from the first‐in‐human safety and feasibility pilot study involving the PS3 System.

Methods and Results:

The primary objective of this first‐in‐human study was to evaluate the safety and feasibility of acute percutaneous septal‐lateral shortening by using the PS3 System in patients immediately prior to clinically‐indicated surgical mitral valve repair. Two patients were enrolled. Patient One had severe aortic insufficiency with moderate functional mitral regurgitation. The PS3 System reduced the MR grade from 2+ to 1+ with a decrease in the mean septal‐lateral systolic (SLS) dimension from 38 to 27 mm (29% reduction). Patient Two had severe ischemic mitral regurgitation in the setting of severe multi‐vessel disease and prior infero‐posterior infarct. MR grade was reduced from 3+ to 1+ with a decrease in the mean SLS dimension from 36 to 25mm (31% reduction). There were no procedural complications and both patients proceeded to pre‐planned cardiac surgery, where the devices were explanted under direct visualization.

Conclusions:

The PS3 System has been safely translated from the preclinical setting to first‐in‐human implantation. Both patients studied experienced a reduction in MR after device implantation, with significant SLS shortening. Further clinical trials will be needed to assess long‐term efficacy and durability. © 2007 Wiley‐Liss, Inc.
Late DES thrombosis: A lot of smoke, very little fire?
Authors: Fischell Tim A. , Holmes David R.
Published: February 2007

Recent studies and editorials have stirred controversy and generated tremendous publicity in the lay press related to the safety of drug‐eluting stents (DES) for the treatment of coronary artery disease. Questions have been raised regarding the risks of late, or very late stent thrombosis with DES. The purpose of this editorial and review of stent thrombosis is to illuminate some counterpoints to some of the attention surrounding the issues of late DES thrombosis. The risks of DES stent thrombosis versus BMS may have been overstated by flawed studies. Late stent thrombosis does occur with both BMS and DES, and may or may not be modestly higher with DES. The time course of very late “DES thrombosis,” suggests that peristent plaque ruptures and disease progression in the target vessel may cause some, or many of these events. There is still much to be learned about the biology of DES. Although there is a small risk of late thrombosis with DES, there is little question that this technology provides benefit to the vast majority of patients compared with prior revascularization strategies, using balloon angioplasty, BMS, or bypass surgery. Substantial resources should be devoted to creating more biocompatible DES systems, and to minimizing the risks of both early and late stent thrombosis. © 2007 Wiley‐Liss, Inc.
Fenestrated endovascular grafts for juxtarenal aortic aneurysms: A step by step technical approach
Authors: Moore Randy , Hinojosa Carlos A. , O'Neill Sean , Mastracci Tara M. , Cinà Claudio S.
Published: February 2007

Fenestrated endovascular aortic aneurysm repair is a valuable alternative for patients who are at high risk for open surgery, but have unsuitable anatomy for infrarenal endovascular repair due to a short aneurysmal neck. Recognizing that this is an evolving and complex technology, we present a step by step approach to the surgical technique that may be useful for endovascular therapist interested in the management of these complex patients. © 2007 Wiley‐Liss, Inc.
Early restenosis following biodegradable stent implantation in an aortopulmonary collateral of a patient with pulmonary atresia and hypoplastic pulmonary arteries
Authors: McMahon Colin J. , Oslizlok Paul , Walsh Kevin P.
Published: February 2007

Traditionally, the implantation of stents in young children with small blood vessels has been avoided as the presence of a metallic or fixed stent structure limits the ability to further dilate the stent with vessel growth. Pulmonary atresia with ventricular septal defect and hypoplastic pulmonary arteries represents one such cohort where the placement of fixed nondegradable stents has been difficult. We report a 2‐month‐old girl with pulmonary atresia, VSD, and multiple aorto‐pulmonary collaterals with severely hypoplastic pulmonary arteries who underwent placement of a biodegradeable magnesium stent within a stenotic aorto‐pulmonary collateral. Although there was an initial significant increase in vessel diameter, significant restenosis occurred 4 months after stent placement. This to our knowledge represents the first case of the use of biodegradable stents in a child with severely hypoplastic pulmonary arteries. Although further refinements in stent technology are required, this development will hopefully usher in a new era of potential intervention in children previously deemed unsuitable for stent placement. © 2007 Wiley‐Liss, Inc.
A Microstructure Heat Exchanger for Quenching the Metabolism of Mammalian Cells
Authors: Wiendahl C. , Brandner J. J. , Küppers C. , Luo B. , Schygulla U. , Noll T. , Oldiges M.
Published: February 2007

Metabolomics, the quantification of intracellular metabolites, is a powerful tool that has proven useful in microbial strain and fermentation process development. The crucial step is the rapid quenching of the cellular metabolism to preserve the intracellular situation as it is in the bioreactor until (MS‐based) analysis. For microbial systems and plants this can be achieved by using ice‐cold methanol (–40 °C) or liquid nitrogen, but for mammalian cells in suspension no reliable technique is yet available. Here, a metallic microstructure heat exchanger is presented which allows cooling of a CHO cell suspension from cultivation temperature (37 °C) to 0 °C in less than one second without any detectable cell damage or cell disruption even at very high cell densities up to 8 · 106 cells/mL.
Herstellung von funktionalisierten oxidischen Nano‐ und Mikropartikeln und deren Verwendung
Authors: Gellermann C. , Ballweg T. , Wolter H.
Published: February 2007

Das Fraunhofer‐Institut für Silicatforschung ISC beschäftigt sich bereits seit vielen Jahren mit der Synthese, Charakterisierung und Verarbeitung von Partikeln auf Basis nichtmetallischer Verbindungen. Beispielsweise werden anorganische und hybride Mikro‐ und Nanopartikel für keramische, optische und medizinische Anwendungen entwickelt. Es handelt sich im Gegensatz zum klassischen Mahlgut bevorzugt um kugelförmige Partikel. Hergestellt werden sie über nasschemische Verfahren wie Emulsions‐ und Fällverfahren, Sol‐Gel‐Technologie oder Aerosolmethoden.
Allicin inhibits cell polarization, migration and division via its direct effect on microtubules
Authors: Prager‐Khoutorsky Masha , Goncharov Igor , Rabinkov Aharon , Mirelman David , Geiger Benjamin , Bershadsky Alexander D.
Published: February 2007

Allicin (diallyl thiosulfinate) is a major biologically active component of garlic that is known to inhibit cell proliferation and induce apoptosis. The effects of allicin are attributed to its ability to react with thiol groups. However, the mechanism underlying the cytostatic activity of allicin, as well as the identity of the relevant subcellular targets, are not known. In the present study, we found that the effects of allicin on cell polarization, migration, and mitosis are similar to the effects of microtubule‐depolymerizing drugs such as nocodazole. Moreover, treatment of cultured fibroblasts with micromolar doses of allicin results in microtubule depolymerization in cells within minutes of its application, without disrupting the actin cytoskeleton or inducing direct cytotoxic effects. Furthermore, allicin blocks the polymerization of pure tubulin in vitro in a concentration‐dependent manner, suggesting that it acts directly on tubulin dimers. Sulfhydryl (SH)‐reducing reagents such as 2‐mercaptoethanol and dithiothreitol abolish the effect of allicin on microtubule polymerization. Thus, allicin is a potent microtubule‐disrupting reagent interfering with tubulin polymerization by reaction with tubulin SH groups. Cell Motil. Cytoskeleton 2007. © 2007 Wiley‐Liss, Inc.
Accelerated mortality from hydrocephalus and pneumonia in mice with a combined deficiency of SPAG6 and SPAG16L reveals a functional interrelationship between the two central apparatus proteins
Authors: Zhang Zhibing , Tang Waixing , Zhou Rong , Shen Xuening , Wei Zhangyong , Patel Aatish M. , Povlishock John T. , Bennett Jean , Strauss Jerome F.
Published: February 2007

SPAG6 and SPAG16L are proteins localized to the “9+2” axoneme central apparatus. Both are essential for sperm motility and male fertility. These two proteins are also expressed in other tissues containing ciliated cells, such as brain and lung. To study the effects of combined deficiency of these two proteins, a double mutant mouse model was created. The double mutant mice displayed a more profound phenotype of growth retardation and hydrocephalus compared to mice nullizygous for SPAG6 and SPAG16L alone. The double mutant mice died younger, and mortality was significantly higher than in single mutant mice. In addition, the double mutant mice demonstrated pneumonia and its complications, including hemorrhage, edema, and atelectasis, phenotypes not observed in mice nullizygous for mutations in the individual genes. No other cilia‐related phenotypic change was detected in double mutant mice including lateralization defects. The ultrastructure of cilia in both the brain and lung of the double mutant mice appeared normal. This model of combined SPAG6 and SPAG16L deficiency provides a new platform to study primary ciliary dyskinesia. The findings also demonstrate that SPAG6 and SPAG16L have related roles in controlling the function of cilia in the brain and lung. Cell Motil. Cytoskeleton 2007. © 2007 Wiley‐Liss, Inc.
EhGEF3, a novel Dbl family member, regulates EhRacA activation during chemotaxis and capping in Entamoeba histolytica
Authors: Arias‐Romero Luis E. , de la Rosa Claudia H. Gonzalez , Almaráz‐Barrera Ma. de Jesús , Diaz‐Valencia Juan D. , Sosa‐Peinado Alejandro , Vargas Miguel
Published: February 2007

Rho GTPases are critical elements involved in the regulation of signal transduction cascades from extracellular stimuli to cytoskeleton. The Rho guanine nucleotide exchange factors (RhoGEFs) have been implicated in direct activation of these GTPases. Here, we describe a novel RhoGEF, denominated EhGEF3 from the parasite Entamoeba histolytica, which encodes a 110 kDa protein containing the domain arrangement of a Dbl homology domain in tandem with a pleckstrin homology domain, the DH domain of EhGEF3 is closely related with the one of the Vav3 protein. Biochemical analysis revealed that EhGEF3 is capable of stimulating nucleotide exchange on the E. histolytica EhRacA and EhRho1 GTPases in vitro, however only a partial GEF activity toward Cdc42 was observed. Conserved residue analysis showed that the N816 and L817 residues are critical for EhGEF3 activity. Cellular studies revealed that EhGEF3 colocalises with EhRacA in the rear of migrating cells, probably regulating the retraction of the uroid and promoting the activation of these GTPase during the chemotactic response toward fibronectin, and that EhGEF3 also regulates EhRacA activation during the capping of cell receptors. These results suggest that EhGEF3 should have a direct role in activating EhRacA, and in bringing the activated GTPase to specific target sites such as the uroid. Cell Motil. Cytoskeleton 2007. © 2007 Wiley‐Liss, Inc.
Feasibility and Accuracy of Sentinel Lymph Node Biopsy After Preoperative Chemotherapy in Breast Cancer Patients With Documented Axillary Metastases
Authors: Shen Jeannie , Gilcrease Michael Z. , Babiera Gildy V. , Ross Merrick I. , Meric‐Bernstam Funda , Feig Barry W. , Kuerer Henry M. , Francis Ashleigh , Ames Frederick C. , Hunt Kelly K.
Published: February 2007

BACKGROUND.

The feasibility and accuracy of sentinel lymph node (SLN) biopsy in patients with breast cancer after preoperative chemotherapy has been demonstrated in a number of large, single‐institution studies. However, a relative contraindication to SLN biopsy after preoperative chemotherapy is the presence of axillary metastases at initial diagnosis. The objective of this study was to determine the feasibility and accuracy of SLN biopsy after preoperative chemotherapy in patients with documented axillary metastases at presentation.

METHODS.

Between 1994 and 2002, 69 patients who had axillary metastases identified by ultrasound‐guided, fine‐needle aspiration underwent SLN biopsy after treatment on prospective, preoperative chemotherapy protocols. All but 8 patients underwent axillary lymph node dissection (ALND). Those 8 patients either declined additional surgery or were offered enrollment in other institutional protocols.

RESULTS.

The median patient age was 49 years, and the median primary tumor size was 4 cm. The SLN identification rate was 92.8%. Thirty‐one of 64 patients (48.4%) had successfully mapped, positive SLNs. Sixty‐one patients underwent ALND, including 5 patients who did not have an SLN identified. In the 56 patients in whom a SLN was identified and an ALND was performed, 10 patients had a false‐negative SLN (25%).

CONCLUSIONS.

SLN biopsy was feasible after preoperative chemotherapy, even in patients who initially presented with cytologically proven, lymph node‐positive disease. However, the false‐negative rate of SLN biopsy in this group of patients was much higher than that observed in clinically lymph node‐negative patients. Based on the current results, the status of the SLN cannot be used as a reliable indicator of the presence or absence of residual disease in the axilla in this patient population. Cancer 2007. © 2007 American Cancer Society.
An efficient time‐domain damping solvent extraction algorithm and its application to arch dam–foundation interaction analysis
Authors: Zhong Hong , Lin Gao , Li Jianbo , Chen Jianyun
Published: February 2007

The dynamic structure–unbounded foundation interaction plays an important role in the seismic response of structures. The damping solvent extraction (DSE) method put forward by Wolf and Song has a great advantage of simplicity, with no singular integrals to be evaluated, no fundamental solution required and convolution integrals avoided. However, implementation of DSE in the time domain to large‐scale engineering problems is associated with enormous difficulties in evaluating interaction forces on the structure–unbounded foundation interface, because the displacement on the corresponding interface is an unknown vector to be found. Three sets of interrelated large algebraic equations have to be solved simultaneously. To overcome these difficulties, an efficient algorithm is presented, such that the solution procedure can be greatly simplified and computational effort considerably saved. To verify its accuracy, two examples with analytical solutions were investigated, each with a parameter analysis on the domain size and amount of artificial damping. Then with the parameters suggested in the parameter study, the complex frequency–response functions and earthquake time history analysis of Morrow Point dam were presented to demonstrate the applicability and efficiency of DSE approach. Copyright © 2007 John Wiley & Sons, Ltd.
Mechanism of mitochondrial 7A6 antigen exposure triggered by distinct apoptotic pathways: Involvement of caspases
Authors: Nagahara Yukitoshi , Tanaka Masato , Shinomiya Takahisa
Published: February 2007

Background:

During the early stages of apoptosis, 7A6 antigen is exposed on mitochondria. 7A6 antigen is observed in various cells and is thought to be a specific marker of apoptosis determination. However, the exposure mechanism of 7A6 during apoptosis is poorly understood.

Methods:

In this study, we used two major distinct (mitochondria‐mediated and receptor‐mediated) apoptotic pathways to elucidate the 7A6 exposure pathway. Jurkat cells were incubated with either a mitochondrial permeability transition pore open reagent FTY720, or anti‐Fas antibody. 7A6 exposure was detected with a specific antibody, Apo2.7. Other apoptosis phenomena, including DNA fragmentation, caspase activation, and mitochondrial membrane potential decreases, were also observed to explore the correlation with 7A6 exposure.

Results:

Both FTY720 and anti‐Fas antibody were found to activate caspase‐3 and exposed 7A6, to subsequently fragment DNA. Mitochondrial membrane potential decrease did not correlate to 7A6 exposure. When mitochondrial dysfunction was inhibited by the overexpression of Bcl‐2, FTY720‐induced 7A6 exposure was blocked, whereas 7A6 was still exposed in anti‐Fas antibody treatment. Caspase inhibitor attenuated 7A6 exposure in both apoptotic pathways, suggesting that 7A6 exposure on mitochondria is a downstream effect of caspase activation.

Conclusions:

7A6 antigen is exposed in a caspase‐dependent manner. 7A6 exposure does not require mitochondrial perturbation. © 2007 International Society for Analytical Cytology
Semi‐automated imaging system to quantitate Her‐2/neu membrane receptor immunoreactivity in human breast cancer
Authors: Joshi Aparna S. , Sharangpani Girish M. , Porter Kyle , Keyhani Sedigheh , Morrison Carl , Basu Amitabha S. , Gholap Gauri A. , Gholap Abhi S. , Barsky Sanford H.
Published: February 2007

Background:

Immunocytochemical methods for quantitating Her‐2/neu immunoreactivity rest on subjective semi‐quantitative interpretations with resulting interobserver, intraobserver, and fatigue variability.

Methods:

To standardize and quantitate measurements of Her‐2/neu immunoreactivity, we created epithelial‐recognition and specific membrane‐recognition algorithms, which could image breast cancer cells against a background of stroma, compartmentalize the cancer cell into nucleus, cytoplasm and membrane, and quantitate the degree of Her‐2/neu membrane immunoreactivity based on both gray scale intensity and RGB colorimetric determinations. Image acquisition utilized either scanner or microscope with attached camera with a resolution of 20 pixels/10 μm. Areas of 150 whole slides were screened and the regions of interest manually selected for image processing. Three hundred TMA cores were directly processed. Images were acquired by jpg conversion of svs virtual slides or direct jpg photomicrograph capture. Images were then assessed for quality and processed.

Results:

The digital algorithms successfully created a semi‐automated imaging system whose algorithm‐based ordinal values for Her‐2/neu both strongly correlated with the subjective measurements (intraclass correlation: 0.84; 95% confidence interval: 0.79–0.89) yet exhibited no run variability. In addition, the algorithms generated immunocytochemical measurements of Her‐2/neu on an expanded continuous scale, which more reliably distinguished true Her‐2/neu positivity from true Her‐2/neu negativity (determined by FISH) than subjective or algorithmic ordinal scale measurements. Furthermore, the continuous scale measurements could better resolve different levels of Her‐2/neu overexpression than either subjective or algorithmic ordinal interpretation. Other semi‐automated analysis systems have been used to measure Her‐2/neu and other cellular immunoreactivities, but these either have required proprietary hardware or have been based on luminosity differences alone. In contrast, our algorithms are independent of proprietary hardware and are based on not just luminosity but also many other imaging properties including epithelial recognition and membrane morphology.

Conclusion:

These features provide a more accurate, versatile, and robust imaging analysis platform. © 2007 International Society for Analytical Cytology
A computerized spectrophotometric instrumental system to determine the “vertical velocity” of sperm cells: A novel concept
Authors: Saha Sudipta , Paul Debashis , Mukherjee Ashutosh , Banerjee Somnath , Majumder Gopal Chandra
Published: February 2007

Background:

The presently available cell motility‐analyzers measure primarily the “horizontal” velocity and there is no instrument available for “vertical” velocity measurement. This development was based on the turbidimetric method of sperm motility analysis.

Methods:

Sperm was layered at the bottom of the cuvette containing buffer solution and exposed to the spectrophotometric light path at different heights to track the vertically moving sperms. The vertical movement was materialized with the development of an electromechanical up–down movement devise for the cuvette accomplished with the help of a cuvette holder‐stepper motor‐computer assembly. The entire system was controlled by the necessary motion control, data acquisition, and data processing softwares developed for cuvette movement and data analysis.

Results:

Using goat sperm as the model a unique computer‐based spectrophotometric system has been developed for the first time to determine the average “vertical” velocity of motile cells.

Conclusions:

Undertaking upward movement against gravity is much tougher as compared with horizontal movement. Consequently average vertical velocity is expected to be a much better identifying parameter for assessing semen and other motile cell quality. The novel instrumental system developed by us has thus the potential for immense application in human infertility clinics, animal‐breeding centres, centres for conservation of endangered species, and also for research work on vertical velocity of spermatozoa and other motile cells, such as bacteria, protozoa, etc. © 2007 International Society for Analytical Cytology
ICOS and B7 costimulatory molecule expression identifies activated cellular subsets in rheumatoid arthritis
Authors: Ruth Jeffrey H. , Rottman James B. , Kingsbury Gillian A. , Coyle Anthony J. , Haines G. Kenneth , Pope Richard M. , Koch Alisa E.
Published: February 2007

To better define important cell subsets expressing activation markers in rheumatoid arthritis (RA), we compared selective lymphocyte and monocyte B7H1, B7H2, B7RP.1, B7RP.2, and inducible costimulatory molecule (ICOS) expression from normal peripheral blood (NL PB), RA PB, and RA synovial fluid (SF) by multicolor flow cytometry and immunohistochemistry. RA SF memory lymphocytes expressed B7RP.1 and B7RP.2, suggesting that T‐cells may function as antigen presenting cells (APCs) in RA joints. We found similar results for ICOS expression. RA SF CD14+ monocytes also expressed B7RP.1 (an ICOS ligand) and the homologous ligand B7RP.2, identifying monocytes as potential mediators of antigen processing and lymphocyte activation in RA. Furthermore, we found an increased population of RA SF CD14+ monocytes expressing B7H1 and B7H2. [The FACS analysis was supported by immunohistochemistry, showing intense lymphocyte and APC (macrophages with dendritic morphology) ICOS staining in RA synovial tissue (ST). Overall, these results define elevated populations of memoryT‐lymphocytes expressing proinflammatory B7 molecules in RA SF that either stimulate T cells through ICOS (via ICOS ligands B7RP.1 and B7RP.2), or down‐regulate RA ST T‐lymphocytes through B7H1 and B7H2.] Therefore, in the same joint, there may exist positive and negative influences on the inflammatory response, and perhaps, the negative signals dominate as joint inflammation resolves. © 2007 International Society for Analytical Cytology
Photothermal flow cytometry in vitro for detection and imaging of individual moving cells
Authors: Zharov Vladimir P. , Galanzha Ekaterina I. , Tuchin Valery V.
Published: February 2007

Background:

Photothermal (PT) cytometry has recently demonstrated great potential for the label‐free detection of nonfluorescent cells under static conditions. The goal of our investigation was to expand this technique to the detection of flowing cells in vitro.

Methods:

Cells in flow were irradiated with short, tunable laser pulses (420–2,300 nm, 8 ns), and the absorbed energy was detected by monitoring of the temperature‐dependent variations in the refractive index in the cells with a second, collinear probe beam in two modes: (a) PT imaging of single cells with a pulsed probe beam (639 nm, 13 ns) and (b) thermolens monitoring of the integral PT responses from individual cells as whole with a continuous‐wave probe beam (633 nm, 2 mW).

Results:

PT flow cytometry at the current speed of analysis of 10 cell/s, with the capability to image selected cells of interest flowing at velocities up to 2 m/s, demonstrated the capability for (a) label‐free detection of flowing single cells (e.g., blood and cancer cells) on the basis of the differences in their endogenous absorption properties, (b) identification of cells labeled with gold nanoparticles, (c) rapid cell viability testing, (d) aggregation immunoassay, and (e) optimization of selective nanophotothermolysis.

Conclusions:

PT cytometry can be extended to the study of cells in flow. This new technique increases the speed of cell analysis approximately 102 times over that of conventional PT technique, with the potential to achieve a rate of 104–105 cells/s in specific PT applications, which has previously been realized only with cells under static conditions. © 2007 International Society for Analytical Cytology
Current literature in diabetes
Authors:   John Wiley & Sons, Ltd.
Published: February 2007

In order to keep subscribers up‐to‐date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of diabetes/metabolism. Each bibliography is divided into 26 sections: 1 Reviews; 2 General; 3 Genetics; 4 Epidemiology; 5 Immunology; 6 Obesity; 7 Prediction and Prevention; 8 Intervention: a) General; b) Care; c) Drug Therapy; d)Economics; e) Gene therapy; f) Nursing; g) Nutrition; h) Surgery; i) Transplantation; 9 Pathology and Complications: a) General; b) Cardiovascular; c) Eye disease; d) Gestational and fetal; e) Neurological; f) Podiatrical; g) Renal; 10 Endocrinology & Metabolism; 11 Experimental Studies; 12 Diagnosis and Techniques. Within each section, articles are listed in alphabetical order with respect to author
Total immunoglobulin of rat thymocytes and thoracic duct lymphocytes
Authors: Jensenius J. C. , Williams A. F.
Published: February 2007

The total immunoglobulin of rat thoracic duct lymphocytes (TDL) and thymocytes has been assayed in extracts of detergent‐solubilized cells. Immunoglobulin was found in thymocytes in much larger amounts than expected from cell surface assays. The main classes involved were IgA and IgG2a+2b, with very little IgM being detected. The variability in the amount detected and the increase with age suggested that the immunoglobulin was coming from antibody‐forming cells in the thymus.

TDL contained large amounts of internal IgA, but virtually no hidden IgG2a+2b or IgM. The IgA was in large lymphocytes which also had surface immunoglobulin. Most of the IgM in cell extracts seemed to be derived from the cell surface. It was not found in amounts greater than estimated by cell surface assays, and was confined to small lymphocytes which carried large amounts of cell surface immunoglobulin. Less than 1000 molecules per cell of IgM was detected in thoracic duct lymphocytes with little surface immunoglobulin after they had been solubilized in 0.33 % sodium dodecyl sulfate, 1 % Triton X‐100 or 9 M urea + 1.5 M acetic acid.
Inhibition of complement‐dependent lymphocyte rosette formation: a possible test for activated complement products
Authors: Ezer G. , Hayward A. R.
Published: February 2007

Complement‐dependent rosette formation by human adenoid lymphocytes could be inhibited by preincubating the lymphocytes with fresh serum activated in vitro. Similar rosette inhibition was seen when lymphocytes were incubated in serum of patients with immune‐complex‐associated conditions, but not by normal serum, suggesting that this test may have clinical usefulness.
The differentiation function of T cell‐replacing factor in nu/nu spleen cell cultures
Authors: Askonas Brigitte A. , Schimpl Anneliese , Wecker E.
Published: February 2007

The effect of T cell‐replacing factor (TRF) on B cells was studied in spleen cell cultures from athymic nu/nu mice with particular emphasis on its possible role in proliferation and/or differentiation of precursor cells.

In contrast to B cell mitogens, such as lipopolysaccharide, TRF does not significantly increase thymidine incorporation nor does it lead to the development of an increased number of plaque‐forming cells in the absence of test antigen. It was found that under conditions of maximal induction of plaque‐forming cells by TRF, i.e. TRF administration 1–2 days following commencement of tissue culture and antigenic stimulation, there was a proportional increase in levels of IgM production relative to total protein synthesis by the cells. In such cultures, Ig formation represented up to 37 % of total protein synthesis. Although the background level of Ig production varied in different cultures, TRF reproducibly led to a 1.5 to 4‐fold increase in proportional Ig synthesis.

The results suggest that some proliferation takes place before TRF is added and indeed before it can act. This is supported by the finding that conditions of reduced cell proliferation (lowered temperature) before the addition of TRF prevent subsequent plaque responses. In contrast, the same treatment applied later on and simultaneously with TRF addition still permits a significant increase in the number of PFC. X‐irradiation of the culture on day 2, immediately prior to TRF addition, still permits an increase in proportional Ig synthesis.

Thus, it appears that a major component of the function of TRF, i.e. the nonantigen‐specific soluble T cell factor, is a differentiation signal favoring Ig production. Mitosis is required before the differentiation signal can be received, and some controlled concomitant proliferation is not excluded.
T cell recognition of cell surface antigens. I. Specificity
Authors: Wekerle H. , Feldman M.
Published: February 2007

Mouse fibroblast monolayers can be used as an immunoadsorbent to separate normal, unsensitized rat lymphocytes with receptors for foreign cell surface antigens. We used this approach to investigate if the specificity of thymus‐dependent cellular immune reactions is based on a functional diversity of the T lymphocytes recognizing the relevant antigens. T lymphocyte diversity was demonstrated by the following findings.

Lymphocytes that are adsorbed to fibroblasts of a given phenotype are relatively restricted in their reactivity to cellular antigen. They strongly react against the adsorbing monolayer type, but their reactivity to another, third party fibroblast type is decreased.

Lymphocytes that were preabsorbed on one fibroblast type and transferred to fresh monolayer cultures decreased their reactivity to the absorbing fibroblast type, but could fully react against unrelated third party fibroblasts.

Pretreatment of the lymphocytes with relevant subcellular antigen prevents their specific adherence to fibroblast monolayers, and, thus, recognition of cellular antigen.

Using mosaic fibroblast monolayers composed of fibroblasts of two unrelated phenotypes, we were able to demonstrate two different lymphocyte populations, each characterized by the capacity to recognize either of the adsorbing fibroblast types.
Hapten‐specific tolerance in mice. I. Induction with hapten‐coupled syngeneic erythrocytes
Authors: Hamilton J. A. , Miller J. F. A. P.
Published: February 2007

A specific suppression of the splenic anti‐NIP (4‐hydroxy‐5‐iodo‐3‐nitropheyl)acetyl plaque‐forming cell response to NIP. FGG (fowl IgG) was obtained in CBA/J mice by pretreatment with NIP‐coated syngeneic erythrocytes. If the plaque assay was carried out at 7 days after challenge with NIP. FGG, a complete suppression of the indirect anti‐NIP plaque‐forming cell (PFC) response could be obtained, but there was no significant decrease in the direct anti‐NIP PFC response at this stage. Complete suppression of the day 7 indirect PFC response occurred within 5–7 days after the NIP‐coated erythrocyte treatment, and lasted for 1–2 months. The degree of suppression was found to depend on the dose of the erythrocytes and on the amount of NIP coupled to them. On closer examination of the anti‐NIP PFC response at different time intervals after the NIP. FGG challenge, it became apparent that there was a slight increase in the indirect anti‐NIP PFC response at days later than day 7. A definite suppression of the direct anti‐NIP PFC cell response was observed earlier than at day 7.

The state of hapten‐specific suppression could be reversed by the addition of syngeneic spleen cells at the time of antigen challenge. The suppression was found to extend to the serum anti‐NIP antibody levels and could also be induced in animals previously primed with NIP‐FGG.
Hapten‐specific tolerance in mice. II. Adoptive transfer studies and evidence for unresponsiveness in the B cells
Authors: Hamilton J. A. , Miller J. F. A. P. , Kettman J.
Published: February 2007

The suppression fo the anti‐NIP ((4‐hydroxy‐5‐iodo‐3‐nitrophenyl)acetyl) plaque‐forming cell (PFC) response elicited in mice by treatment with NIP‐coated syngeneic erythrocytes could be transferred by spleen cells into irradiated recipients. This was evidenced by the lack of an indirect anti‐NIP PFC response 7 days after cell transfer and challenge with NIP. FGG (fowl IgG). This state of specific unresponsiveness could be serially transferred by spleen cells into a second irradiated recipient. The hapten‐specific suppression in the first recipient could be reversed by addition of normal spleen cells, but not by cortisone‐resistant thymus cells. The lesion appears to be in the T cell‐depleted population, since the suppression could be reversed by supplementing with T cell‐depleted normal spleen cells. In vitro incubation of spleen cells from tolerant animals did not restore the capacity of these cells to produce an anti‐NIP PFC response in irradiated recipients. In vitro incubation of normal spleen cells with sera from tolerant animals did not prevent these spleen cells from producing a normal anti‐NIP PFC response in irradiated recipients. The adoptive secondary response response to NIP. FGG was inhibited by injection of NIP‐coated syngeneic erythrocytes on the same day as the adoptive transfer of the NIP. FGG primed spleen cells and the challenging antigen.

It would seem that NIP‐coupled syngeneic erythrocytes, which are presumably poor stimulators of T cells, can suppress NIP‐specific B cells, perhaps by gaining direct access to the surface of these cells.
Metabolism of H‐2 and Thy‐1 (Θ) alloantigens in murine thymocytes
Authors: Vitetta Ellen S. , Uhr J. W. , Boyse E. A.
Published: February 2007

The metabolism of Thy‐1 and H‐2 alloantigens was studied in murine thymocytes radiolabeled with 3H precursors or surface radioidinated. It was found that 125I‐labeled Thy‐1 is rapidly shed from cultured thymocytes, whereas H‐2 alloantigens are not. [3H]galactose‐labeled Thy‐1 is also released from cultured thymocytes, whereas [3H]leucine‐labeled H‐2 alloantigens are not. These results support the concept that H‐2 alloantigens are integral macromolecules of the plasma membrane and suggest further that Thy‐1 is a peripheral one. Possible mechanisms underlying shedding are discussed.
Differential induction of anti‐trinitrophenyl plaque‐forming cell responses to lightly and heavily conjugated trinitrophenylated heterologous and autologous erythrocytes in mice
Authors: Naor D. , Morecki Shoshana , Mitchell G. F.
Published: February 2007

Various anti‐TNP PFC (2,4,6‐trinitrophenyl plaque‐forming cell) responses were obtained by injecting C3H mice with different conjugates of trinitrophenylated sheep red cells (TNP‐SRC). Mice which were injected with lightly conjugated TNP‐SRC (TNP0.14SRC) produced indirect anti‐TNP PFC 4 days after injection, while mice which were injected with heavily conjugated TNP‐SRC (TNP14SRC) produced both direct and indirect anti‐TNP PFC or direct anti TNP PFC only.

Heavily conjugated trinitrophenylated autologous mouse red cells elicited a low direct anti‐TNP PFC response 4 days after injection. The system is another example of the capacity to modify antibody responses by modification of the antigen.
In vitro antibody response of primed rabbit peripheral blood lymphocytes to Group A variant streptococcal polysaccharide
Authors: Read S. E. , Braun D. G.
Published: February 2007

Peripheral blood lymphocytes obtained from rabbits at various times after a primary course of immunization with streptococcal Group A‐variant vaccines were successfully stimulated in vitro with this vaccine. Day 5 cultures contained about 81 % IgM and only 19 % IgG plaque‐forming cells, day 10 cultures contained only 38 % IgM and 62 % IgG plaques, and day 15 cultures contained predominantly IgG plaques (83 %) and far fewer IgM plaques (17 %). Concomitantly, IgM and IgG secretion into the media was shown. Analysis of the secreted IgG antibodies by isoelectric focusing showed in principle that the clones stimulated in vitro were those that had determined the in vivo response. These data demonstrate the circulation of clonal progenitor cells in the rabbit peripheral blood.
Equivalent responsiveness to branched polysaccharides and their dinitrophenyl conjugates in the Biozzi high and low responder lines of mice
Authors: Howard J. G. , Courtenay Barbara M. , Desaymard Catherine
Published: February 2007

Dose response curves for two thymus‐independent branched polysaccharides, levan and dextran B 1355, have been compared by direct plaque‐forming cell assays in the Biozzi high (Ab/H) and low (Ab/L) responder lines of mice. In contrast with all of many other antigens so far tested, equivalent IgM responses were elicited by native levan (mol. wt. 2 × 107), Pseudomonas levanicum vaccine and native dextran (mol. wt. 4 × 107). Partially depolymerized levan (mol. wt. 5 × 104 − 7 × 104) was surprisingly more immunogenic in Ab/L than in Ab/H mice. Furthermore, the tolerance threshold dose of both native and depolymerized levans was lower in the Ab/H line, the converse of previous findings with the linear polysaccharide SIII. Equivalent anti‐DNP responses were obtained in the two lines when they were immunized with the hapten conjugated with levan, whereas conventional high/low separation was obtained when polymerized flagellin was used as carrier.

It is concluded that nonspecific “high” and “low” responsiveness in Ab/H and Ab/L mice results not from an intrinsic difference in their B cells, but from selective involvement of an extrinsic regulation mechanism. Evidence which implicates divergence in antigen handling by macrophages as a primary factor, and the exceptional behavior of the branched polysaccharides in evading this difference are discussed.
Changes in affinity of IgM antibodies in amphibian larvae
Authors: Du Pasquier L. , Haimovich J.
Published: February 2007

The increase in affinity of anti‐2, 4‐dinitrophenyl (DNP) antibodies of IgM class in tadpoles was followed as a function of time after administration of antigen by the inhibition of inactivation of DNP‐bacteriophage T4. A 10‐fold increase in binding affinity was observed over a period of 3–4 weeks after injection.
Surface morphology of murine B and T lymphocytes: A comparative study by scanning electron microscopy
Authors: Polliack A. , Hämmerling U. , Lampen N. , de Harven E.
Published: February 2007

A variety of murine lymphocytes of known B or T derivation obtained from different lymphoid organs were prepared for scanning electron microscopy (SEM) by the critical point drying method after collecting the cells by aspiration onto silver membranes. Comparison of SEM appearances of cells prepared by this technique and serological classification accoding to surface antigens showed that most T cells had smooth surfaces with few micorvilli, while many B lymphocytes were moderately to markedly villous.

Further evidence for the above correlation was obtained by examining thymic cells and enriched B or T cells populations. Thymic cell suspensions containing less than 5 % B cells showed over 80 % generally smooth cells bye SEM. Enriched T cell populations, obtained by mass cytolysis of lymph node preparations with anti‐Ia or anti‐Ig sera or by purification through nylon fibern columns, contained over 85 % T cells, and more than 75 % of them were of the were of the smooth cell type.

A similar correlation was noted for enriched B cell populations obtained by cytolysis of lymph node cells with anti‐Thy‐1 serum, and by lysis of EAC‐rosettes. Over 90 % of these cells were identified as B cells by immunologic methods and approximately 75 % had moderate to markedly villous surfaces. The 15 % difference can be accounted for by the existence of a subpopulation of smooth B cells. Direct observation of EAC‐rosettes confirmed that most B cells had moderate to large numbers of the smooth cells seen in enriched B cell populations may represent precursors or B lymphocytes at different stages of differentiation.

These result indicate that murine T and B lymphocytes, like their human counterparts, can be recognized in many cases under the SEM on the basis of their surface mophology. Smoother B and more villous T cells are difficult to classify to SEM without parallel immunologic identification.
Immunoglobulin heavy chain mRNA in mitogen‐stimulate B cells
Authors: Stevens R. H. , Askonas Brigitte A. , Welstead Jacqueline L.
Published: February 2007

This paper relates the synthesis of DNA, immunoglobulin and heavy chain (H) MRNA in murine spleen cells following activation of B cells with lipopolysaccharide from E. Coli (LPS).

Spleen cells (CBA/H mice) were cultivated with 10 % FCS and 10 μg LPS/ml. 4 h pulses with [3H]thymidine showed that DNA synthesis was stimulated within the firstb day following LPS activation and exhibited a sharp peak at 24 h. The shape of the DNA synthesis curve suggests that the cells susceptible to LPS stimulation are activated in a synchronous manner.

Stimulation of H‐chain mRNA (H‐mRNA) synthesis proceeded raidly (within 6 h of LPS addition) and peaked around 24 h, in parallel to DNA synthesis. The H‐mRNA was isolated and quantitated by making use of its interaction with IgG [1, 2]. The actual level of H‐mRNA in the culture increased three‐fold during the first 24 h and then doubled within the next 48 h. Estimates of the actual number of H‐mRNA were approximately 200 molecules H‐m‐RNA/cell on day 0 rising to 1800/cell on day 3. In such a mixed cell populations these figures will be accurate only within a factor of 2–3 (at least 35 % B cells in spleen cell suspensions at the commencement of the culture, with up to 35–60 % of plasma blasts by day 3 and 4 of LPS treatment).

Translation of the lymphoid cell mRNA in oocytes from Xenopus laevis demonstrated that stimulation of H‐mRNA synthesis was restricted to μ‐mRNA, although some γ‐mRNA was present in the original spleen cells.

High levels of synthesis of immunoglobulin followed after a lag period of about 24 h following LPS addition peaking after 48 h adn 72 h; the proportional Ig production relative to total protein synthesis reached 26 % on days 3 and 4. Stimulation of Ig production was limited to IgM.

Rapid stimulation of mitosis and H‐mRNA synthesis thus precedes the maximum synthesis of Ig molecules, suggesting a translational block on the transport of H‐mRNA from the nucleus during early stages of activation.
Soluble HL‐A antigens in serum. I. Isolation and Purification
Authors: Oh S. K. , Pellegrino M. A. , Ferrone S. , Sevier E. D. , Reisfeld R. A.
Published: February 2007

A new method was developed which utilizes fractional salting out, gel filtration, ion exchange chromatography and polyacrylamide gel electrophoresis for the isolation and purification of soluble HL‐A antigens from serum. The method produced purified antigens possessing HL‐A 5,9 specificities with yield up to 60 % of that detected in the original serum. Up to 150‐fold increase in specific HL‐A antigenic activity above that in the starting material could be achieved as measured by the ability of the purified antigens to specifically inhibit the cytotoxic activity of HL‐A alloantisera against selected target cells. Electrophoretically purified HL‐A antigens with different specificities appear to have a similar molecular size, i.e. 33 000, but differ in their electric charge properties. β2‐microglobulin (β2m) seems to be noncovalently associated with HL‐A antigens present in serum, but during purification β2m is progressively lost until at the final purification by polyacrylamide gel electrophoresis, the material is completely devoid of β2m.
Turnover of radioiodinated and of leucine‐labeled immunoglobulin M in murine splenic lymphocytes
Authors: Melchers F. , Cone R. E.
Published: February 2007

Lactoperoxidase‐catalyzed radioiodination of cell surface proteins and biosynthetic incorporation of tritiated leucine were used to study the size and turnover of cell‐associated immunoglobulins in splenic lymphocytes of different size from BALB/c, C3H, and nu/nu mice.

Small spleen cells, separated from large cells by velocity sedimentation, showed a single slow rate of turnover (t1/2= 10–30 h) of surface radioiodinated or leucine‐labeled IgM released as the monomeric 7–8 S subunit of IgM. Mitogen‐activated large B cells and nonstimulated large spleen cells, separated by velocity sedimentation, released leucine‐labeled IgM in an initial rapid phase (t1/2= 2–4 h) as 19 S IgM, and later released 7–8 S IgM slowly (t1/2= 10–30 h). The iodination reaction changed neither the biphasic mode of turnover, nor, even at higher concentration of H2O2, the size of the actively secreted 19 S IgM. Radioiodination of mitogen‐activated large cells or of unstimulated large cells labeled only the slowly released 7–8 S IgM, not the actively secreted 19 S IgM. Large cells of nonstimulated spleen, however, released radioiodinated as well as leucine‐labeled IgM also rapidly (t1/2= 1–3 h). These rapidly released IgM molecules were found to be 7–8 S IgM subunits.

Our results indicate that these turnover rate and size differences of radioiodinated and of leucine‐labeled IgM released from murine spleen cells are in part resulting from the differences in the methodology of labeling and are in other parts due to different small and large splenic lymphocytes releasing IgM of different size at different rates.
B cell tolerance induced by polymeric antigens. I. Comparison of thedose and epitope density requirement for inactivation of primed and unprimed B cells in vivo
Authors: Klaus G. G. B. , Humphrey J. H.
Published: February 2007

Hapten [2,4‐dinitrophenyl (DNP)]‐specific tolerance was induced in nonimmun or DNP‐hemocyanin (DNP‐KLH) primed mice by administering hapten‐conjugated type 3 pneumococcal polysaccharide (DNP‐lys‐S3). The dose of DNP‐lys2.5−S3 required to suppress the primary anti‐DNP antibody responses was appaprox‐imately ten times higher than that required to suppress the secondary response Large doses of lightly substituted antigen (DNP‐lys0.6−S3) had no effect on prim‐ary antibody responses, while small doses of this conjugate suppressed 90—95 % of the secondary response. The conclusion from this (presumably B cell) tolerance model is that B lymphocytes “mature” in their susceptibility to tolerization following primary contact with immunogen, since primed cells are inactivated by lower doses of tolerogen, and by tolerogen with lower epitope density, than no immune B cells. These and other data suggest that the tolerance threshold of B lymphocytes is related to their state of differentiation, and especially to their antigen‐binding characteristics.