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PubMed2005

CD19 function in central and peripheral B-cell development.

Although the B-cell antigen receptor (BCR) factors most prominently in the maintenance and differentiation of mature B cells, it is now appreciated that co-receptor molecules can positively or negatively modulate signals through the BCR. Co-receptors are functionally defined as modifiers of BCR engagement and signal transduction, and are distinct from other accessory molecules that act independently to regulate B-cell growth. The co-receptor CD19 functions to augment signals by the pre-BCR/BCR and in doing so can modulate B-cell fate decisions at multiple stages of development. In mature B cells, CD19 also associates with complement receptor 2 (CR2/CD21) and is pivotal for transducing signals induced by co-recognition of complement C3d-fixed antigens by the BCR and CD21. In this article, we focus on recent progress in the understanding of CD19 function through the characterization of mouse models that relate in vivo function to biochemical properties of CD19.

Animals↗
PubMedDate not supplied

On the diagnosis and pathogenesis of intramural maxillary cysts.

In order to study the etiology of the intramural maxillary cyst, which is the origin of the choanal polyp, an antrotomy was performed on 27 patients with such cysts. The cyst-fluid was analysed with respect to protein distribution and bacterial growth. The findings indicate an inflammatory process characterized by high concentrations of immunoglobulins and by consumption of complement and antiproteases. The growth of bacteria, primarily an oral flora found in the cyst-fluids studied, and the sites of cyst attachment, may indicate an epithelial residue of the dental list as the origin of the intramural cyst. It is further suggested that bacterial substances will provoke an inflammatory response, giving rise to an expansion of the cyst. In all cases studied, the cyst-fluid was capable of gelling after a couple of minutes at room temperature. This observation seems to be a reliable diagnostic procedure at antral aspiration, distinguishing the cyst-fluid from the serous transudate of the serous sinusitis, which according to our results, does not have this capacity to form a gel.

Adolescent↗
PubMed2000

Passive transfer of demyelination by serum or IgG from chronic inflammatory demyelinating polyneuropathy patients.

Chronic inflammatory demyelinating polyneuropathy (CIDP) is regarded as an autoimmune disorder, but no clearly defined autoimmune mechanism has been described. Although most patients respond to plasma exchange, no convincing role for autoantibodies has yet been demonstrated. In this study, we have successfully passively transferred disease using sera and purified IgG from 4 of 12 patients responsive to plasma exchange by bypassing the blood-nerve barrier by intraneural injection or opening it by activated T cells. The sera from CIDP patients or purified IgG produced marked conduction block and demyelination, but normal sera or IgG or that from patients with multiple sclerosis or other neuropathies did not. These observations strongly support an important role for anti-myelin/Schwann cell autoantibodies in the pathogenesis of CIDP at least in some patients.

Action Potentials↗
PubMed2000

Myelin widenings and MGUS-IgA: an immunoelectron microscopic study.

A few studies have reported a variety of nonspecific histological lesions in patients with IgA monoclonal gammopathies and polyneuropathy. In our case, using electron microscopy, we observed widenings of the myelin lamellae identical to those commonly described in IgM neuropathies with anti-myelin-associated glycoprotein activity. Using immunoelectron microscopy, we demonstrated a direct involvement of IgA in myelin lesions. The search for a direct link between monoclonal dysglobulinemia, regardless of type, and polyneuropathy is important and may influence treatment.

Aged↗
PubMed1996

Chronic inflammatory demyelinating polyneuropathy in dogs and cats.

Over the past several years, we have accumulated data on a spontaneous demyelinating peripheral neuropathy that is not well identified in domestic animals. This disorder occurs in dogs and cats of either sex and does not appear breed-related. Onset of signs is usually insidious and the course is typically chronic, sometimes relapsing, and often slowly progressive. Mature animals of any age may be affected. Clinical signs include tetraparesis, sometimes progressing to tetraplegia, stumbling gait, and hyporeflexia. Motor nerve conduction velocities are decreased. Pathologically, changes in teased single fibers from peripheral nerves are dominated by multifocal paranodal demyelination. Scattered, thinly myelinated fibers are seen on semithin sections. Ultrastructural studies reveal macrophages within myelinated fibers stripping the myelin sheaths, naked and remyelinating axons, and focal/multifocal endoneurial mononuclear cells. Indirect immunofluorescence revealed positive IgG staining in peripheral nerve myelin sheaths from two dogs. The course of the disease, clinical signs, electrophysiology, and pathology have similarities to chronic inflammatory demyelinating polyneuropathy in people.

Age Factors↗
PubMed2002

DNA gene fusion vaccines against cancer.

The ability of DNA vaccination to induce effective immune responses has been shown in a range of preclinical disease models. However, the potency of DNA vaccines must be further improved for their use in patients. DNA fusion vaccine strategies, whereby target antigens are genetically linked to immuno-enhancing molecules, are currently being explored. The ease of DNA manipulation has allowed incorporation of a wide variety of molecules able to promote antigen uptake, processing and presentation by professional antigen-presenting cells, to provide critical CD4 T-cell help and to activate more effective immune effector pathways. These strategies are particularly important for cancer vaccines to increase their immunogenicity and to overcome tolerance.

Animals↗
PubMed1991

Attenuation of intra-operative surgical stress response has no influence on post-operative degranulation of polymorphonuclear granulocytes.

Degranulation of polymorphonuclear (PMN) granulocytes, complement activation, and the endocrine metabolic response to hysterectomy were compared in two groups of patients receiving either general anaesthesia (GA group) or combined epidural analgesia and general anaesthesia (GAE group). The B-leucocyte and the cortisol responses were attenuated in the GAE group. There was no sign of complement activation. The post-operative rise in elastase-alpha-1-proteinase levels 4 h post-operatively on the first, second and third post-operative days was similar in the two groups. Plasma lactoferrin values were significantly elevated 4 h post-operatively and reached pre-operative values on Day 1 in both groups. Attenuation of the surgical stress response during uncomplicated hysterectomy did not influence the post-operative increase in proteinase activity. Mediators generated at the site of surgical trauma may account for the PMN degranulation observed after major surgery.

Adult↗
PubMed1989

[Pemphigus herpetiformis--the value of simple diagnostic measures].

Herpetiform pemphigus is a rare variety of pemphigus vulgaris. Although the final diagnosis requires thorough clinical, histological and immunological investigations, there are simple examinations which may be carried out at once (such as assessment of blister stability, negative Nikolski's sign, predominance of eosinophils, spongiotic and non-acantholytic epidermal cells in the Tzanck smear). These ad hoc findings may help the practising dermatologist to tell herpetiform pemphigus from other blistering diseases. We discuss and evaluate the various diagnostic procedures regarding herpetiform pemphigus.

Aged↗
PubMedDate not supplied

The effect of physical training on patients with rheumatoid arthritis: changes in disease activity, muscle strength and aerobic capacity. A clinically controlled minimized cross-over study.

For decades, physical training of rheumatoid arthritis (RA)-patients has been controversial, especially for patients with active disease. The aim of this study was to investigate whether RA-patients could receive graduated training without increasing the activity of the disease. In a controlled cross-over study the effect of graduated progressive training has been evaluated in 18 RA-patients with moderately active disease. The training was performed twice weekly with aerobic conditioning and strength exercises progressing to strenuous exercises over an 8-week period. The design was a crossover project with two groups obtained by minimisation. After training the patients had significantly fewer swollen joints than before. Training of the muscles acting over the swollen joints resulted in more than a 35% decrease in the number of swollen joints. The hemoglobin level increased significantly after the training period. The erythrocyte sedimentation rate, the complement factor C3d, and the number of sore joints remained unchanged. A decrease in the need for medicine was non-significant. From this study it appears that RA-patients with some activity are trainable without aggravating the disease, even in the chronically swollen joints. The rheumatoid arthritis activity decreased with fewer swollen joints and higher hemoglobin level after training.

Adult↗
PubMedDate not supplied

Prekallikrein activation in the adult respiratory distress syndrome.

Prekallikrein is the zymogen form of plasma kallikrein, a proteolytic enzyme of the contact system of blood coagulation, fibrinolysis and kinin formation. To assess whether prekallikrein was activated in the adult respiratory distress syndrome (ARDS), we examined plasma samples from 12 critically ill patients including five individuals with ARDS. Using the ratio between functional prekallikrein and prekallikrein-kallikrein antigen as an index for prekallikrein activation, we found that prekallikrein was extensively activated in patients with ARDS, while this was significantly less in the case of critically ill patients without ARDS. Following activation of prekallikrein in plasma, kallikrein reacts with its substrates and with protease inhibitors, among which the alpha 2-glycoprotein C1-inhibitor. Thus, we examined whether C1-inhibitor of critically ill individuals was modified in a way suggesting that it had reacted with kallikrein. Such a modification was found in the five patients with ARDS, while it was not detectable in the seven patients without ARDS. This observation further confirmed the activation of prekallikrein in patients with ARDS. We suggest that plasma kallikrein-mediated reactions, which include bradykinin release and neutrophil activation, may contribute to the pathogenesis of ARDS.

Adolescent↗
PubMed1983

Heterogeneity in electrophoretic mobility of C3-derived molecules expressing D but not C-epitopes following in vivo activation of the complement system.

Four different populations of C3-derived molecules expressing D but not C epitopes were identified following in vivo activation of the complement system. The four molecular forms, differing in electrophoretic migration velocity, were assigned the nos. 1, 2, 3 and 4 after decreasing electrophoretic mobility. Analysis of the time-dependent changes in the relative concentration of the different molecular forms demonstrated an increase in the plasma concentration of population 4 and a decrease of populations 2 and 3, whereas form 1 remained rather constant after acute activation of the complement system.

Animals↗
PubMed1984

[Immunologic findings in juvenile Mediterranean kala-azar].

The course of immunological parameters in a 2 year old patient with mediterranean kala-azar is reported. Plasma-fibronectin was reduced to 33% of the normal value at the time of diagnosis. When the clinical symptoms of the disease were most severe, a marked activation of complement without demonstrable circulating immune complexes was observed. Therapy with sodium-stibogluconate lead to improvement of the child's condition, normalization of complement reaction and fibronectin levels, and detection of circulating immune complexes. The activity of the disease seems to be well indicated by the level of C-reactive protein and the complement cleavage product C3 d. Incubation of living Leishmania donovani with normal human serum leads to activation of complement in vitro.

Antibodies↗
PubMed1983

Abnormal leucocyte locomotion induced by haemodialysis membranes. A clue to dialysis leucopenia.

In a study on polymorphonuclear leucocyte (PMN) chemotaxis and random locomotion carried out on 16 patients undergoing haemodialysis and on the same functions in normal PMN which were separated from plasma and subjected to laboratory haemodialysis, it was shown that random PMN locomotion is reduced and that there is a concomitant fall in the leucocyte count in haemodialyzed patients. The laboratory haemodialysis demonstrated that serum factors were not responsible for the PMN dysfunction, which lasted for the entire period of the procedure. The changes were observed only when cellulose membranes were used, and not when haemodialysis was performed with polyacrilonitrile membranes. The reduction in random PMN locomotion may be involved in the genesis of dialysis leucopenia, as well as in the increased susceptibility of uremic patients to infections.

Cell Movement↗