Macrophage response to peripheral nerve injury: the quantitative contribution of resident and hematogenous macrophages

Whereas local microglial cells of the CNS rapidly respond to injury, little is known about the functional role of resident macrophages of the peripheral nervous system in nerve pathology. Using bone marrow chimeric rats, we recently identified individual resident endoneurial macrophages that rapidly became activated after nerve injury. However, the extent of local macrophage activation and its quantitative contribution to the total macrophage response is unknown. We now have created chimeric mice by transplanting bone marrow from green fluorescent protein (GFP)-transgenic mice into irradiated wild-type mice, allowing easy differentiation and quantification of hematogenous and resident endoneurial macrophages. After sciatic nerve crush injury, both GFP(-) and GFP(+) resident macrophages, the latter having undergone physiological turnover from the blood before injury, rapidly underwent morphological alterations and increased in number. Proliferating GFP(-) and GFP(+) resident macrophages were abundant and peaked 3 days after injury. A major lesion-induced influx of hematogenous macrophages with a disproportionate increase of GFP(+) macrophages was not observed until Day 4. Throughout all time points examined, GFP(-) resident macrophages were strikingly frequent, reaching maximum numbers 9.5-fold above baseline. There was also a notable proportion of GFP(-) resident endoneurial macrophages phagocytosing myelin and expressing major histocompatibility complex class II. Our results demonstrate for the first time that the rapid response of resident endoneurial macrophages to nerve injury is quantitatively important and that local macrophages contribute significantly to the total endoneurial macrophage pool during Wallerian degeneration.     

Effect of depressive symptoms on survival after heart transplantation

OBJECTIVE: This study explored the value of preoperative self-reported assessment for depression and anxiety in patients who had undergone heart transplantation (HTx). The initial sample was divided into subgroups of patients with ischemic (ICMP) and dilated cardiomyopathy (DCMP). Patient depression and anxiety scores were measured in both subgroups and their impact on pre- and postoperative mortality investigated. METHOD: An initial sample of 152 patients with either ICMP (N = 57) or DCMP (N = 95) and end-stage heart disease awaiting heart transplantation were assessed in a multidimensional longitudinal study, including psychological and somatic variables. One hundred and three patients received a HTx and were followed up for a mean of 4.4 years. Proportional hazard models were computed to test for the influence of psychosocial and somatic factors on outcome. RESULTS: Preoperative depression and state anxiety scores were significantly higher in the ICMP group. In addition to donor and recipient age, ICMP patients in the preoperative high depression group also showed a significantly higher mortality after HTx. This result remained significant even after controlling for sociodemographic and somatic variables. CONCLUSIONS: Patient self-reported depression, but not anxiety, can contribute to the identification of subgroups of patients with an unfavorable outcome after HTx. It therefore may be helpful to screen for depression, particularly in patients with an ischemic cause of their end-stage heart disease. Specific intervention programs should be further developed and evaluated.     

Einige Befunde zur Sinnesphysiologie der Kaltblüterzecke Amblyomma testudinis

Zusammenfassung Aus eigener Zucht stammende Larven, Nymphen und Imagines von Amblyomma testudinis wurden auf ihre Sinnesleistungen hinsichtlich Phototaxis, Thermotaxis, Geotaxis und Chemotaxis untersucht. Es ergab sich ein entwicklungsabhängiger Wandel im phototaktischen Verhalten von anfangs positiver Phototaxis bei den Larven über indifferente Phototaxis bei vollgesogenen Larven und nüchternen Nymphen zu negativer Phototaxis bei vollgesogenen Nympen sowie - und -Imagines. Sämtliche Entwicklungsstadien mit Ausnahme der -Imagines verhalten sich temperaturindifferent vor dem Kontakt mit einem Wirt; vollgesogene Larven und Nymphen dagegen bevorzugen niedrige Temperaturen. Nymphen und Imagines, die noch nicht gesogen haben, reagieren negativ geotaktisch. Sie erklettern vermutlich in der Natur die Spitzen von Pflanzen und Steinen, um dort das Vorbeikriechen eines Wirtes abzuwarten. Imagines von Amblyomma testudinis reagieren mit einer positiven Chemotaxis auf Schlangen stärker als auf Kröten. Auch Substrat aus Schlangenbehältern enthält mindestens für 30 Std nach der Entfernung der Schlangen chemotaktisch wirksame Stoffe.

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Contributions to sensory physiology of the tick Amblyomma testudinis

Summary Phototaxis, thermotaxis, geotaxis and chemotaxis of larvae, nymphs and adults of Amblyomma testudinis from own breedings were studied. The phototactic behaviour changed according to the different stages of development: unfed larvae were positively phototactic, fed larvae and unfed nymphs were indifferent, fed nymphs but also the adults showed a negative phototaxis.—All stages of development besides the females reacted without any preference for a distinct temperature, whereas larvae and nymphs after feeding prefered lower temperatures.—Unfed nymphs and adults were negatively geotactic which corresponds to their natural behaviour of climbing plants for catching hosts.—Adults of Amblyomma testudinis showed a higher rate of chemotaxis for snakes than for toads; substrate from snake cages containes chemotaxis inducing substances for more than 30 hours after elimination of the snakes.

     

Protein expression of MMP-13, uPA, and PAI-1 in pseudocapsular and interface tissue around implants of loose artificial hip joints and in osteoarthritis

Matrix metalloproteinase 13 (MMP-13), urokinase type plasminogen activator (uPA), and plasminogen activator inhibitor type-1 (PAI-1) have been reported to be involved in aseptic loosening of artificial hip joints. This study for the first time presents the protein levels of all of these factors in synovial-like interfaces between bone and prosthesis and in pseudocapsular tissues surrounding the artificial joint in patients with aseptic loosening (n=17) measured by ELISA. No differences were observed in the antigen expression of MMP-13, uPA, and PAI-1, comparing interface and pseudocapsular tissue. Also, no significant correlation between the protein expression of these factors and years from arthroplasty to revision or to type of fixation (cemented vs. cementless) was observed. As control, MMP-13, uPA, and PAI-1 antigen levels were also determined in the synovium of patients with osteoarthritis (n=10). Yet, the antigen levels of MMP-13, uPA, and PAI-1 in tissue specimens from patients with aseptic loosening of artificial hip joints were significantly higher compared to their expression in synovial capsular tissues obtained from patients with osteoarthritis. In conclusion, this study shows that elevated protein levels of uPA, PAI-1, and MMP-13 in periprosthetic pseudocapsular and interface tissues from patients after total hip replacement due to aseptic loosening seem not to be associated with the patient outcome.     

Hormone replacement therapy and vigilance: double-blind,placebo-controlled EEG-mapping studies with an estrogen-progestogen combination (Climodien,Lafamme) versus estrogen alone in menopausal syndrome patients

The aim of the double-blind, placebo-controlled study was to investigate the effects of a continuous combined estrogen-progestogen treatment (Climodien, Lafamme) as compared with estrogen alone on vigilance in insomniac postmenopausal syndrome patients, objectified by EEG mapping. METHODS: In a 3-arm, 2-month parallel group design phase, patients received a combination of estradiol valerate 2 mg and the novel progestogen dienogest 3 mg (Climodien 2/3) or estradiol valerate 2 mg alone or placebo. In a subsequent open-label phase, all patients received estradiol valerate 2 mg+dienogest 2 mg (Climodien 2/2). EEG mapping was carried out before and after the 2-month double-blind phase as well as after the 2-month open-label treatment. RESULTS: As compared with placebo, Climodien 2/3 induced a marked and highly significant increase in absolute power in all frequency bands, specifically in alpha-2 activity. Moreover, a significant increase in relative alpha-2 power, a decrease in relative delta and beta power as well as an acceleration of the dominant frequency and of the delta and alpha centroids suggested a marked improvement in vigilance. In contrast, under estradiol valerate 2 mg alone, only a slight augmentation of alpha and attenuation of relative delta and beta power occurred, suggesting only a slight vigilance improvement as compared with placebo. Thus, dienogest 2 mg increased the estrogen effect, which was also confirmed by a statistical evaluation of the differences between Climodien 2/3 and estradiol valerate alone (augmentation of alpha-2, attenuation of relative beta, acceleration of the dominant frequency). Moreover, Climodien 2/2 also markedly increased alpha-2 power, decreased relative beta-2 power and accelerated the alpha centroid. Finally, comparing Climodien 2/3 with Climodien 2/2, there was even a dose-efficacy relation. CONCLUSIONS: Estradiol valerate 2 mg improves vigilance slightly, thereby confirming previous findings. The additional administration of dienogest does not minimize the effect of estrogen, but on the contrary increases it, which makes the combination superior to both placebo and estradiol valerate alone. Vigilance improvement may be of great therapeutic benefit to menopausal syndrome patients at a time when increased adaptability is needed to adjust to increasing sexual, marital, occupational and social difficulties known to occur specifically in this period of life.     

The volume-activated chloride current in endothelial cells from bovine pulmonary artery is not modulated by phosphorylation

We employed the patch-clamp technique to investigate the effects of various phosphorylation pathways on activation and modulation of volume-activated Cl- currents (I _Cl,vol) in cultured endothelial cells from bovine pulmonary arteries (CPAE cells). Half-maximal activation ofI _Cl,vol occurred at a hypotonicity of 27.5 ± 1.2%. Run-down of the current upon repetitive activation was less than 15% within 60 min. Stimulation of protein kinase C (PKC) by phorbol-12-myristate-13-acetate (PMA) or by (–)-indolactam did not affectI _Cl,vol. Down regulation of PKC activity by a 24-h preincubation of the cells with 0.2 mol/l PMA, or its inhibition by loading the cells with the specific inhibitory 19–31 pseudosubstrate peptide, did not influenceI _Cl,vol. Trifluoperazine and tamoxifen fully blockedI _cCl,vol with concentrations required for half-maximal inhibition of 3.0 and 2.4 mol/1 respectively. This inhibitory effect is probably not mediated by the calmodulin-antagonistic action of these compounds, because it occurs at free intracellular [Ca²⁺] of 50 nmol/l, which are below the threshold for calmodulin activation. The tyrosine kinase inhibitor herbimycin A (1 ol/1) and genistein (100 ol/1) did not affectI _Cl,vol Exposing CPAE cells to lysophosphatidic acid (1mol/1), an activator of p42 MAPkinase and the focal adhesion kinase p125^FAK in endothelial cells, neither evoked a Cl^– current nor affectedI _Cl,vol Neither wortmannin (10 mol/1), an inhibitor of MAP kinases and of PI-3 kinase, nor rapamycin (0.1 mmol/1), which interferes with the p70S6 kinase pathway, affectedI _Cl,vol Exposure of CPAE cells to heat or Na-arsenite, both activators of a recently discovered stress-activated tyrosine phosphorylation pathway, neither activated a current nor affected the hypotonic solution-induced Cl^– current. We conclude that none of the studied phosphorylation pathways is essential for the activation of the Cl^– current induced by hypotonicity.     

Elongated peptides,not the predicted nonapeptide stimulate a major histocompatibility complex class I-restricted cytotoxic T lymphocyte clone with specificity for a bacterial heat shock protein

The peptides recognized by an H-2D^b-restricted CD8 cytotoxic T lymphocyte (CTL) clone which is specific for the 60-kDa mycobacterial heat shock protein (hsp) and cross-reacts with stressed host cells were characterized. None of the nonapeptides from hsp60 conforming to the H-2D^b binding motif were able to sensitize target cells for lysis by this CTL clone. Sequence analysis of the stimulatory fraction from a trypsin digest of hsp60, together with synthetic peptide studies, defined a cluster of overlapping epitopes. Carboxy-terminal extension by at least one amino acid of the nonamer predicted to bind best to H-2D^b was essential for CTL recognition. Two such elongated peptides, a 10-mer and a 12-mer stimulated the clone at similarly low concentrations in the 100 pM range. We assume that these two peptides comply best with the natural epitope. In contrast, the 11-mer was inactive. The stimulatory 10-mer bound to H-2D^b with an efficacy similar to that of the nonapeptide corresponding to the H-2D^b motif, as revealed by peptide induced major histocompatibility complex (MHC) surface expression on RMA-S cells and competitive blocking of epitope recognition by the nonamer. Binding of these carboxy-terminally extended peptides to the MHC groove can be explained by anchoring through the amino acid residue Asn in position 5 of the peptide and by intrusion of the hydrophobic carboxy-terminal Ala (10-mer) or Leu (12-mer), but not Gly (11-mer), into the hydrophobic pocket of the H-2D^b cleft. Because the carboxy-terminal part is thus larger than predicted this region of the peptide may arch up from the binding groove. We assume that recognition of steric components of the MHC/peptide complex broaden the range of epitope specificity for a single T cell receptor. This flexibility not only promotes recognition of several overlapping peptides from a single antigen, but may also increase the chance of cross-reaction with similar peptides from unrelated proteins, including autoantigens. Consistent with this latter assumption, the T cell clone cross-recognizes mycobacterial hsp60 and stressed host cells.     

Adenovirus type 12 tumor antigen. II. Immunoprecipitation of protein kinase from infected and transformed cells by antisera to T antigen and some normal rat sera.

Protein kinase was found to be precipitated from adenovirus type 12 (Ad12)-infected KB cells and Ad12-transformed hamster cells by sera of tumor-bearing hamsters and rats: Immunoprecipitates obtained with T antigen reactive sera catalyzed transfer of ³²P from [γ-³²P]ATP to the γ-chain of IgG. Analogous products of control cells were without significant activity. Control hamster sera precipitated no protein kinase from infected and transformed cells. Some control rat sera (syngeneic with immune sera), however, were found to precipitate protein kinase from infected and transformed cells; particularly active in this respect were sera of female breeder rats. When partially purified, highly immunoreactive T antigen preparations from transformed cells were used as a source of enzymatic activity, protein kinase was detected only in precipitates obtained with immune sera.