CD antigens 2001

The most recent Human Leucocyte Differentiation Antigen Workshop ("HLDA7") took place in 2000 in Harrogate, UK and the proceedings are about to be published (Leucocyte Typing VII). New Sections were introduced in this Workship (Dendritic cells, Stem/progenitor cells, Erythroid cells and Carbohydrate Structures) and monoclonal antibodies were selected for which at least some molecular data were already available (to avoid "blind" screening of reagents against known specificities). A total of more than 80 new CD specificities were established (previously the average was less than 30 new CD specificities per Workshop) and these are listed in this article. There is already evidence for the existence of many new leucocyte surface molecules for study at the next HLDA Workshop (in Adelaide in 2004), and we have listed in this article a number of such potential CD candidates (identified following the production of monoclonal antibodies or via gene cloning). There are also today an increasing number of lineage- and/or stage-restricted leucocyte-associated molecules localised within the cell cytoplasm (or nucleus): they will certainly prove of intense in the future for many laboratories studying human haematopoietic cells (regardless of whether a new "intracellular CD" categorisation scheme is devised for such molecules).

Dendritic cells from patients with myeloma are numerically normal but functionally defective as they fail to up-regulate CD80 (B7-1) expression after huCD40LT stimulation because of inhibition by transforming growth factor-beta1 and interleukin-10

Limited response to idiotype vaccination in patients with myeloma suggests that there is a need to develop better immunotherapy strategies. It has been determined that the number of high-potency CMRF44+CD14-CD19- dendritic cells (DCs) in the blood of patients with myeloma (range, 0.03%-0.8% of mononuclear cells [MNCs]; n = 26) was not significantly different from that in controls (range, 0.05%-0.8% of MNCs; n = 13). Expression of the costimulatory molecules CD80 and CD86 on DCs from these patients (mean, 29%+/-17% of MNCs and 85%+/-10% of MNCs, respectively) was also normal (mean, 29%+/-17% and 86%+/-16% of MNCs, respectively). Up-regulation of CD80 expression in response to stimulation by human huCD40LT + interleukin (IL)-2 was significantly reduced on the DCs of patients with myeloma during stable disease (n = 9) and was absent during progressive stages (n = 7) of disease. Similar effects were seen on B cells but not on monocytes of the same group of patients. CD86 expression on DCs was high before (86%) and after (89%) stimulation. Inhibition of CD80 up-regulation was neutralized by either anti-transforming growth factor (TGF)-beta1 or anti-IL-10. Up-regulation of CD80 on DCs of controls was inhibited by rTGF-beta1 in a dose-dependent manner. Serum TGF-beta1 and IL-10 levels were normal in most patients studied. Cytoplasmic TGF-beta1 was increased in plasma cells during progressive disease. Thus patients with myeloma have normal numbers of DCs, but CD80 expression may fail to be up-regulated in the presence of huCD40LT because of tumor-derived TGF-beta1 or IL-10. Autologous high-potency DCs may have to be tested for CD80 up-regulation and biologically modified ex vivo before idiotype priming for immunotherapy.

CD antigens 2001

This paper reviews the Seventh Human Leucocyte Differentiation Antigen (HLDA7) workshop. Due to the limitations of "blind" antibody screening, which had been evident at the previous meeting in 1996, participants at HLDA7 adopted a more selective approach to the choice of antibodies by identifying new CD specificities. This resulted in the addition of more than 80 new CD specificities. Plans for the eighth and subsequent workshops are also previewed.

HIV gp120 receptors on human dendritic cells

Dendritic cells (DCs) are important targets for human immunodeficiency virus (HIV) because of their roles during transmission and also maintenance of immune competence. Furthermore, DCs are a key cell in the development of HIV vaccines. In both these settings the mechanism of binding of the HIV envelope protein gp120 to DCs is of importance. Recently a single C-type lectin receptor (CLR), DC-SIGN, has been reported to be the predominant receptor on monocyte-derived DCs (MDDCs) rather than CD4. In this study a novel biotinylated gp120 assay was used to determine whether CLR or CD4 were predominant receptors on MDDCs and ex vivo blood DCs. CLR bound more than 80% of gp120 on MDDCs, with residual binding attributable to CD4, reconfirming that CLRs were the major receptors for gp120 on MDDCs. However, in contrast to recent reports, gp120 binding to at least 3 CLRs was observed: DC-SIGN, mannose receptor, and unidentified trypsin resistant CLR(s). In marked contrast, freshly isolated and cultured CD11c(+ve) and CD11c(-ve) blood DCs only bound gp120 via CD4. In view of these marked differences between MDDCs and blood DCs, HIV capture by DCs and transfer mechanisms to T cells as well as potential antigenic processing pathways will need to be determined for each DC phenotype.

The relation of self-esteem variability to emotion variability, mood, personality traits, and depressive tendencies

The relation of self-esteem variability to personality, mood, and behavior was investigated. Self-esteem variability was measured by calculating the standard deviation of self-ratings made during a week of experience-sampling. Participants high in self-esteem variability were self-conscious, socially anxious, and avoidant of social contexts. Self-esteem variability was partially independent of the conceptually similar trait of affect-intensity. The contributions of the study to work on self-esteem stability are discussed.

Bitter-sweet symphony: defining the role of dendritic cell gp120 receptors in HIV infection

BACKGROUND

Dendritic cells (DC) are believed to be one of the first cell types infected during HIV transmission. Recently a single C-type lectin receptor (CLR), DC-SIGN, has been reported to be the predominant receptor on monocyte derived DC (MDDC) rather than CD4. The role of other CLRs in HIV binding and HIV binding by CLRs on other types of DC in vivo is largely unknown.

OBJECTIVES AND STUDY DESIGN

Review HIV binding to DC populations, both in vitro and in vivo, in light of the immense interest of a recently re-identified CLR called DC-SIGN.

RESULTS AND CONCLUSIONS

From recent work, it is clear that immature MDDC have a complex pattern of HIV gp120 binding. In contrast to other cell types gp120 has the potential to bind to several receptors on DC including CD4 and several types of C type lectin receptor, not just exclusively DC-SIGN. Given the diverse types of DC in vivo future work will need to focus on defining the receptors for HIV binding to these different cell types. Mucosal transmission of HIV in vivo targets immature sessile DCs, including Langerhans cells which lack DC-SIGN. The role of CLRs and DC-SIGN in such transmission remains to be defined.

Dendritic cells: On the move from bench to bedside

As dendritic cells increasingly become the adjuvant of choice in new approaches to cancer immunotherapy, a degree of protocol standardization is required to aid future large-scale clinical trials.

The clinical features, risk factors and outcome of thrombotic thrombocytopenic purpura occurring after bone marrow transplantation

In this study, we retrospectively analysed the clinical features, risk factors and outcome of 22 patients with thrombotic thrombocytopenic purpura (TTP) occurring after allogeneic stem cell transplantation. All but two of these patients received stem cells from unrelated donors (UDs), two-thirds were female, three-quarters were adults and leukaemia was the major reason for transplant. The incidence of TTP was 20 out of 332 patients (6%) with UD transplants and two out of 104 recipients (2%) of matched sibling allografts (P = 0.16). In order to ascertain basic demographic risk factors for the development of TTP, we compared the 22 patients with 434 patients who did not develop TTP. Compared with patients who did not develop TTP, patients with TTP were nearly three times older (P < 0.001) and were more than twice as likely to be female (P = 0.001). Because > 90% of patients were recipients of UD marrow, we then compared the 20 UD-bone marrow transplantation (BMT) patients with 60 randomly selected UD-BMT patients who did not develop TTP. On univariate analysis, age and female gender were again significant risk factors, as was grade II-IV acute graft-versus-host disease (GvHD) (P = 0.002), and there was a trend towards an association with chronic GvHD (P = 0.083). However, after logistic regression analysis, only age and sex remained significant (P < 0.001 and 0.009 respectively). We report an 86% mortality with only three survivors out of 22 patients, and one of these remains thrombocytopenic and red cell transfusion dependent, possibly in part because of graft hypoplasia. Six out of 17 patients responded to plasmapheresis, but the majority of them ultimately succumbed because of TTP, often in association with GvHD or fungal infection.

A study of the variation in tuberculosis incidence and possible influential variables in Manchester, Liverpool, Birmingham and Cardiff in 1991-1995

SETTING AND OBJECTIVE

The reversal of the decline in United Kingdom tuberculosis rates has sparked a resurgence of interest in the epidemiology and prevention of tuberculosis in the UK. In this paper we quantify the primary factors explaining the variability in the electoral ward level relative risk of tuberculosis in Manchester, Liverpool, Birmingham and Cardiff.

DESIGN

Ecological analysis of the incidence of tuberculosis in 397 wards using hospital admissions data as a proxy for tuberculosis incidence. Admissions were evaluated from the financial years 1991/1992 to 1994/1995. Ward level covariates included measures of country of birth, ethnicity and various socio-economic measures.

RESULTS

Separate analyses were carried out for pulmonary and non-pulmonary tuberculosis. For pulmonary tuberculosis the final model included measures of the ward population born in India and Pakistan, overcrowded housing and not-owner-occupied housing. For non-pulmonary tuberculosis the covariates were ward population born in India and Pakistan, overcrowded housing and the proportion of households with no car.

CONCLUSIONS

The country of birth of the ward population is the single most influential explanatory factor in the variability of the ward rates for both pulmonary and non-pulmonary tuberculosis in these four cities. Measures of poverty are of secondary importance.

Ether--lipid (alkyl-phospholipid) metabolism and the mechanism of action of ether--lipid analogues in Leishmania

Ether-lipid (alkyl-phospholipid) analogues such as Miltefosine possess potent in vitro and in vivo anti-leishmanial activity and these compounds are currently undergoing clinical trials in humans. These analogues are also effective against Trypanosoma cruzi and Trypanosoma brucei subspecies but their mode of action is not known. Leishmania have high levels of ether-lipids and these are mainly found in the glycosylphosphatidylinositol-anchored glycolipids and glycoproteins present on the surface of the parasites. In Leishmania mexicana promastigotes we have studied both the initiating steps for the biosynthesis of ether-lipids, and key remodelling steps. The effect of Miltefosine and Edelfosine, on key enzymes involved in the metabolism of ether-lipids has been studied. The enzymes include dihydroxyacetonephosphate acyltransferase, sn-l-acyl-2-lyso-glycero-3-phosphocholine and sn-l-alkyl-2-lyso-glycero-3-phosphocholine acyltransferases. We confirm that the initiating steps in ether-lipid metabolism in Leishmania are present in glycosomes, and that Miltefosine or Edelfosine did not perturb these enzymes. The metabolism of the latter phosphatidylcholine base intermediates, which may be involved in the remodelling of acyl- and alkyl-glycerophospholipids, was also seemingly associated with glycosomes. Both Miltefosine and Edelfosine inhibited this microbody (glycosomal) located alkyl-specific-acyl-CoA acyltransferase in a dose-dependent manner with an inhibitory concentration of 50 microM. It is suggested therefore that a perturbation of ether-lipid remodelling could be responsible for the anti-leishmanial action of these drugs.

Angiographic findings and clinical correlates in patients with cardiogenic shock complicating acute myocardial infarction: a report from the SHOCK Trial Registry. SHould we emergently revascularize Occluded Coronaries for cardiogenic shocK?

OBJECTIVES

We sought to delineate the angiographic findings, clinical correlates and in-hospital outcomes in patients with cardiogenic shock (CS) complicating acute myocardial infarction.

BACKGROUND

Patients with CS complicating acute myocardial infarction carry a grave prognosis. Detailed angiographic findings in a large, prospectively identified cohort of patients with CS are currently lacking.

METHODS

We compared the clinical characteristics, angiographic findings, and in-hospital outcomes of 717 patients selected to undergo angiography and 442 not selected, overall and by shock etiology: left or right ventricular failure versus mechanical complications.

RESULTS

Patients who underwent angiography had lower baseline risk and a better hemodynamic profile than those who did not. Overall, 15.5% of the patients had significant left main lesions on angiography, and 53.4% had three-vessel disease, with higher rates of both for those with ventricular failure, compared with patients who had mechanical complications. Among patients who underwent angiography, those with ventricular failure had significantly lower in-hospital mortality than patients with mechanical complications (45.2% vs. 57.0%; p = 0.021). Importantly, for patients with ventricular failure, in-hospital mortality also correlated with disease severity: 35.0% for no or single-vessel disease versus 50.8% for three-vessel disease. Furthermore, mortality was associated with the culprit lesion location (78.6% in left main lesion, 69.7% in saphenous vein graft lesions, 42.4% in circumflex lesions, 42.3% in left anterior descending lesions, and 37.4% in right coronary artery lesions), and Thrombolysis In Myocardial Infarction (TIMI) flow grade (46.5% in TIMI 0/1, 49.4% in TIMI 2 and 26% in TIMI 3).

CONCLUSIONS

Patients who underwent angiographic study in the SHOCK Trial Registry had a more benign cardiac risk profile, more favorable hemodynamic findings and lower in-hospital mortality than those for whom angiograms were not obtained. Patients with CS caused by ventricular failure had more severe atherosclerosis, and a different distribution of culprit vessel involvement but lower in-hospital mortality, than those with mechanical complications. Overall in-hospital survival correlates with the extent of coronary artery obstructions, location of culprit lesion and baseline coronary TIMI flow grade.

Primary spontaneous pneumothorax: treatment practices in Australia

OBJECTIVE

The aim of the present study was to determine treatment practices for spontaneous pneumothorax (PTX) in Australia.

METHODOLOGY

A questionnaire regarding treatment of PTX was posted to all medically qualified members of the Thoracic Society of Australia and New Zealand resident in Australia.

RESULTS

Fifty-three per cent (n = 226) of questionnaires were returned. Twenty-one responses were judged to be informal and rejected from analysis. The results indicate a general agreement in the treatment of small and large PTX but a wide variation in PTX of intermediate size.

CONCLUSION

Opinion regarding the optimal treatment for PTX of intermediate size was found to vary considerably. There is a need for evidence-based development and publication of best practice guidelines for PTX.

Diagnosis and treatment of breast cancer

This article presents a thorough review of the diagnosis and treatment of breast cancer, the most common type of cancer found among American women. Topics covered in this article include risk factors, screening, types of breast cancer, diagnostic procedures, surgical and nonsurgical treatments, staging, genetic testing, and nutrition and complementary therapies.

An analysis of farmer uptake of formal farm management training in Western Australia

In the last decade some agricultural policy makers and other industry leaders have suggested that farmers will need to upgrade their business management skills to cope with the rapid changes in the agribusiness environment. Anecdotal and research evidence has suggested that many farmers do not perceive this need and are reluctant to participate in formal business management training to upgrade their skills. A study involving focus groups, a survey of training providers and a telephone survey of 197 farm managers investigated if and why farmers in the south-west agricultural region of Western Australia might be reluctant to participate. Two thirds of farmers in the survey had not participated in formal farm business management training. Older, more experienced farmers with lower levels of formal education were the least likely to attend and were less likely to be aware of available training activities. Women who were members of farm management teams (32%) were more likely to attend training than men. Attitudes towards formal training appear to be improving and farmers are aware of the increasing importance of farm business management training. Lack of attendance seems to be related in some instances to a lack of suitable local training activities, a preference for informal over formal learning and a lack of confidence in the relevance of the training. It is suggested that strategies should be developed to provide and deliver suitable training to those sectors of farming community that are not participating in current programs.

[Practice guidelines--legal aspects]

Medical guidelines of professional institutions establish rules for good medical treatment (quality of care). They take the form of international, national, regional and local guidelines and are set up by international and national medical organisations, mainly by medical societies but also by regional (e.g. medical associations in the states) and local institutions (up to hospital departments). The rules of good medical treatment (guidelines) conform to the corresponding medical standard which is defined by scientific knowledge (evidence based medicine), practical experience and professional acceptance. The binding character of the standard for medical practice increases with the reliability of scientific evidence and practical experience. Insofar, medical guidelines which correspond to the standard fulfil a quality assurance function for medical treatment as a means of communication in the medical profession, an implementation function for the enforcement of standards and thus also a protective function for patients. Furthermore, they rationalize decisions of the courts by increasing the transparency of their medical basis and thus also contribute to the quality improvement of legal decisions on medical malpractice. Medical guidelines can also influence social law directives. On principle. Medical guidelines do not include any economic considerations (efficiency) and should be strictly separated from these (principle of separation and transparency). Medical guidelines have to be differentiated from health insurance law directives and recommendations. In addition to the quality assurance function, the function of guaranteeing the efficiency of treatment is a priority for health insurances. These objectives may be in conflict with each other. This paper is mainly concerned with the significance of medical guidelines for medical malpractice law.

Designing interdisciplinary documentation for the continuum of care

An increased emphasis on integrated care delivery and the need to access information across the care continuum led to an assessment and modification of the current documentation system at Summa Health System in Akron, Ohio. The goal was to achieve more complete and concise interdisciplinary charting. This article describes the process the two-hospital system developed to achieve integrated documentation reflecting the patient's progress toward team-defined outcomes. Steps in the evaluation and modification of the old system, lessons learned, and results/implications for quality improvement are shared.

Optimisation of the biology of soft tissue repair

As identified in this review, over the past twenty years there have been a number of very exciting new developments in the quest to optimise soft tissue repair. Comparing fetal soft tissue injuries, which heal by regeneration, to the adult processes of healing by inflammation-induced scar formation has led to a number of insights into how the latter may be improved. Seeding wounds with embryonic stem cells, bridging gaps with cell-derived "engineered tissues", addition of exogenous hyaluronic acid and modification of wounds to either enhance the growth factors which have been implicated in regeneration (e.g. TGF-B3) or block those implicated in scar formation (eg. TGF-B1) have all shown promise. Our group has quantified numerous cellular, molecular, biomechanical and matrix abnormalities of scar in a rabbit model of ligament healing. Based on these studies which we review here, three matrix deficiencies have been identified which appear to have specific implications to scar weakness: organisational "flaws", abnormal hydroxypyridinoline collagen cross-link densities and abnormally small, slow-maturing collagen fibrils. In tests aimed at finding therapeutic solutions in this model, the addition of a 7ug bolus of TGF-B1 at day 21 or 2.5ng/day of TGF-B1 being pumped into a wound x 21 days increased the size of ligament scars but did not improve their material strength. It also did not alter any of the above-noted matrix deficiencies. A liposome-mediated anti-sense gene therapy approach aimed at decreasing the expression of the proteoglycan decorin in 21-day scars, however, has significantly increased the size of scar collagen fibrils as well as improved these scars mechanically. Based on these positive results from a single dose of only one targeted molecule, we believe that this gene therapy approach has great potential for further scar improvement. If combined with some of the other biological strategies reviewed above, a repair which is closer to true regenerative healing of ligaments, and all soft tissues, may eventually be achieved.