Correlates and predictors of obesity-specific quality of life of former participants of a residential intensive lifestyle intervention.

Introduction: The aim of this study was to investigate the relationship between weight loss during and after a unique type of weight loss intervention, namely, a residential intensive lifestyle intervention (ILI), and participants' obesity-specific health-related quality of life (HRQOL) several years after the intervention. In the residential ILI under investigation, participants attended a 10- to 12-week long course away from their daily living environment, namely, at Ubberup Folk High School located in Denmark. Methods: A total of 79 former participants (31 male, mean age 36.6; SD = 12.7 years) who had participated in the intervention on average 5.3 (SD = 3.2) years ago were recruited for this study. They completed a questionnaire on weight-related quality of life (IWQOL-lite) and physical activity, as well as measurements of VO2max, blood pressure, Homeostatic Model Assessment for Insulin Resistance, waist circumference and hand grip strength. Results: The study results showed that weight change after the end of the intervention could predict HRQOL whereas how much weight they lost during the intervention could not. Furthermore, almost all of the investigated physiological factors were related to participants' current HRQOL. Waist circumference showed relationships with four of the five aspects of HRQOL. Conclusion: Focusing on behavioural change, adhering to improved lifestyle and maintaining weight loss after the end of the intervention seem to be the key not only for cardio-metabolic risk factors but also for sustainable HRQOL.

The role of community in the development of elite handball and football players in Denmark.

The primary purpose of this study was to investigate the effect of the place of early development in a sample of Danish male elite and youth handball and football players. The sample included 366 handball and football players from the elite Danish league in the season 2011-2012 and a comparison sample of youth players under the age of 12 from 2003, including 147,221 football and 26,290 handball players. Odds ratio analysis showed that both population size and density significantly affected the proportional number of youth players per community and the odds of athletes reaching an elite level in football and handball. The odds for youth player registrations in both handball and football increased in rural in contrast to urban communities. However, elite football players primarily came from communities of high density (>1000 pop./km(2)), whereas elite handball players primarily came from less densely populated communities (100 to <250 pop./km(2)). Furthermore, there seems to be a relation between representation of elite and talent clubs in different communities and the probability of becoming an elite player in both sports. The limited number of elite players in both sports from rural communities may be due to national talent development strategies that do not incorporate development support for clubs in rural areas. Additionally, the results of the study clearly suggest the need to include the youth player population to advance research findings in birthplace effect studies.

Late specialization: the key to success in centimeters, grams, or seconds (cgs) sports.

A controversial question within elite sports is whether young athletes need to specialize early, as suggested by Ericsson et al., or if it is more beneficial to follow the path of early diversification proposed by Côté et al., which includes sampling different sport experiences during childhood and specializing later on during adolescence. Based on a Danish sample of 148 elite and 95 near-elite athletes from cgs sports (sports measured in centimeters, grams, or seconds), the present study investigates group differences concerning accumulated practice hours during the early stages of the career, involvement in other sports, career development, as well as determining whether or not these variables predict membership in the elite group. The results clearly reveal that elite athletes specialized at a later age and trained less in childhood. However, elite athletes were shown to intensify their training regime during late adolescence more than their near-elite peers. The involvement in other sports neither differs between the groups nor predicts success. It can be concluded that factors related to the organization of practice during the mid-teens seem to be crucial for international success within cgs sports. Future research should adopt a longitudinal design with means of drawing causal inferences.

Experiencing flow in different types of physical activity intervention programs: three randomized studies.

This study explores whether inactive individuals can experience flow, a rewarding, psychological state, during an exercise intervention and if there are differences according to the type of intervention they perform. Furthermore, the study investigates if experiencing flow is connected to physiological improvements attained during the exercise intervention. The 12- to 16-week interventions included six randomized intervention groups, two female and four male groups performing continuous running, football, interval running and strength training. The results indicate that all six randomized exercise intervention groups experience rather high levels of flow regardless of whether the intervention is a team or individual sport. Differences in experiencing flow, worry and exertion as well as physiological improvements could be found for the different types of sports and the two genders, with the male football group having the highest score for physiological improvement and the lowest score for worry. A connection between experiencing flow and physiological improvement could not be found. Future research should investigate the influence that the participant's gender and also the type of sport have on experiencing flow, worry and perceived exertion. Furthermore, it should be investigated whether experiencing flow is linked to the long-term compliance of regular physical activity.

The canonical T cell receptor of dendritic epidermal gamma delta T cells is highly conserved between rats and mice.

Two monoclonal antibodies with specificity for rat gammadelta T cell receptor (TCR) were generated. One, called V65, reacts with all CD3+ alphabeta TCR- rat Tcells and thus recognizes a constant determinant of the rat gammadelta TCR (Kühnlein et al., Journal of Immunology 1994, 153: 979). The other, called V45, reacts with approximately 80% of gammadelta T cells in peripheral lymphoid organs. In rat epidermis, V65 but not V45 detects a dense network of the dendritic epidermal Tcells (DETC). Analysis of epidermal RNA by polymerase chain reaction (PCR) indicated that Vgamma3 and Vdelta1 are the predominant, if not exclusive TCR V transcripts present at this site. Sequence analysis of cDNA clones obtained by reverse transcription-PCR with Vgamma3- and Vdelta1-specific primers revealed that the variable domains of rat DETC gamma and delta chains are very homologous to those described in mice (92% and 95% identity at the protein level). The complete conservation between the two species of the amino acid sequences at the V-(D)-J transitions of this monomorphic receptor indicates that the interaction of the DETC TCR with its as yet unknown ligand must be of central importance for DETC function.

MHC class I expression on dendritic cells is sufficient to sensitize for transplantation immunity.

The immunogenicity of an allograft correlates with the number of MHC class II+ antigen-presenting cells (dendritic cells) that it contains. To determine whether these antigen-presenting cells induce not only MHC class II-mediated immune responses, but also physiologically relevant levels of MHC class I immunity, we took advantage of a unique MHC class I+/class II-/CD80+ dendritic cell line (80/1 DC) derived from murine (C3H, H-2k) fetal skin. The 80/1 DC sensitized H-2-disparate recipients for specific transplantation immunity, as evidenced by significantly accelerated rejection (second set) of skin allografts from C3H mice, but not of third-party allografts. As few as 10(2) 80/1 DC, administered by the subcutaneous route, were effective, indicating their high potency as stimulator cells. Several lines of evidence support the hypothesis that the immunization observed was mediated primarily by direct presentation of allo-class I: (i) Blockage of the co-stimulatory molecule CD80 on 80/1 DC abrogated their sensitizing capacity; (ii) equal numbers of a nonprofessional antigen-presenting cell line (L929, C3H origin) as well as dead 80/1 DC failed to accelerate graft rejection; and (iii) injection of syngeneic (BALB/c) Langerhans cells pulsed with 80/1 DC fragments induced a delayed-type hypersensitivity reaction to these fragments but failed to accelerate rejection of C3H skin grafts. We conclude that direct allo-class I immunity can occur in the absence of class II expression when induced by a professional antigen-presenting cell and that this mechanism has biologic relevance in transplantation immunity.

T-cell receptor alpha beta and gamma delta T cells in rat and human skin--are they equivalent?

In the not-so-distant past the skin was generally viewed as a passive target for immune-mediated injury. Over the last decade, however, concepts of a previously unrecognized role for the skin have unfolded, whereby resident bone marrow-derived leukocytes (e.g. Langerhans cells and T cells) initiate and regulate the immune responses that protect it. Their combination with other immunomodulatory resident cells (e.g. keratinocytes, melanocytes, endothelial cells, fibroblasts) led to the idea that the skin may function as a self-sustaining lymphoid tissue. Although T lymphocytes or, at least, certain subpopulations thereof have the general propensity to populate epithelial tissues, there exist major species differences regarding the phenotype of intraepidermal T cells. The purpose of this review is to fill gaps in our understanding of the relationship of rodent skin T cells to T cells identified in human skin and the normal physiologic and pathologic role(s) of these cells.

Induction of the TNF-alpha promoter in the murine dendritic cell line 18 and the murine mast cell line CPII is differently regulated.

While it was recently shown that activation of dendritic cells (DC) results in the production of a number of cytokines, the signal pathways and transcription factors involved in this process have not been described. To address this issue we compared the events resulting in the activation of the human TNF-alpha promoter occurring in the fetal dendritic cell line 18 (DC18) with those in the well-characterized murine mast cell line CPII. As stimuli we employed the protein kinase C inducer, PMA, and the Ca2+ ionophore, ionomycin, both of which are known to activate a large variety of intracellular signaling pathways. In the DC18 cells, PMA alone induces the TNF-alpha promoter in a macrolide-insensitive manner. In contrast, in the mast cell line CPII, both stimuli (PMA plus ionomycin) are necessary for promoter activation which, in addition, is sensitive to immunosuppressive drugs. Mapping of the TNF-alpha promoter showed that in both cell types the so-called kappa factor binding site is the crucial promoter element for the induction. We show that in DC18 cells, this sequence is bound to and controlled by NF-kappaB proteins p50 (NF-kappaB1) and p65 (ReIA), whereas in CPII mast cells, NF-AT and AN factors are the predominant proteins that bind to and control the kappaB element of the TNF-alpha promoter. These and further experimental data indicate that in DC, NF-kappaB factors play a predominant role in the activation of the TNF-alpha promoter and, possibly, of other cytokine promoters.

Autoantibodies against desmoplakin I and II define a subset of patients with erythema multiforme major.

In a previous report, we described autoantibodies against the desmosomal plaque proteins desmoplakin I and II (dp I and II) in patients with erythema multiforme (EM) major. In the present study we investigated ten EM major and eight EM minor patients for circulating autoantibodies and performed clinical and immunomorphological evaluations. Seven out of ten EM major patients revealed anti-dp I and II autoantibodies. Antigens were biochemically characterized by Western blotting and immunoprecipitation of epithelial-cell-derived protein extracts. These autoantibodies bind in vivo to lesional skin/mucosa in a pemphigus-type dotted pattern along the cytoplasmic membranes of keratinocytes. Ultrastructural immunolocalization studies confine in vivo bound autoantibodies to the cytoplasmic desmosomal plaque. Autoantibody binding studies with the sera of such patients demonstrate that the target antigens are not restricted to squamous epithelia but are also expressed in simple and transitional epithelia, on hepatocytes, and on cells of mesenchymal origin, e.g., myocardial cells. Comparing the clinicopathological features of ten patients with EM major, we could not define any discriminating clinical symptoms among patients with or without autoantibodies. Histopathological examination, however, revealed that only patients with EM major and autoantibodies against dp I and II show suprabasal acantholysis in lesional skin and mucous membranes, suggesting a potential role of the humoral immune response in the pathogenesis of this disease. These findings suggest that these autoantibodies define a subset of patients within the clinical spectrum of EM.

Generation of human dendritic cells/Langerhans cells from circulating CD34+ hematopoietic progenitor cells.

Human Langerhans cells (LC) are CD1a+ dendritic cells (DC) that function as potent antigen-presenting cells for primary and secondary immune responses. Limitations in DC/LC numbers, imposed by difficult and tedious isolation procedures, have so far precluded their use as immunogens in the generation and/or augmentation of host responses against various pathogens. Therefore, we have developed a procedure for the generation of human DC/LC from CD34+ hematopoietic progenitor cells (HPC) isolated (mean: 0.7 x 10(6)/ buffy coat and 2.6 x 10(6)/leukapheresis product) and purified ( > 95%) from the peripheral blood of healthy adults. In vitro stimulation of these cells with granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor (TNF)-alpha led to their vigorous proliferation and differentiation resulting in the emergence of CD45+/CD68+/CD3-/CD19-/CD56- leukocytes some of which (mean: 12%) express CD1a and exhibit anti-CD4 and anti-major histocompatibility complex (MHC) class II reactivity. These CD1a- leukocytes include (1) LC as evidenced by the presence of Birbeck granules (BG), (2) CD14+ monocytes, and (3) Birbeck granule-negative cells with a dendritic morphology. Addition of interleukin (IL)-4 to the cytokine cocktail interfered with the development of monocytes and led to a reduction in the overall yield but, on the other hand, resulted in an increased percentage of CD1a+ cells (mean: 24%) among all cells generated. In vitro generated CD1a+, but not CD1a- HPC-derived cells are potent stimulators of the primary mixed leukocyte reaction and, as such, promising candidates for vaccination purposes.

Exogenous hepatitis B surface antigen particles processed by dendritic cells or macrophages prime murine MHC class I-restricted cytotoxic T lymphocytes in vivo.

Injection of low doses of particulate hepatitis B surface Ag (HBsAg) into H-2d mice without adjuvants primes an Ld-restricted, S28-39-specific T cell response. This study indicates that dendritic cells (DC) and macrophages (M phi) both serve as APCs that support priming of CD8+ CTL precursors in vivo to exogenous HBsAg particles. After transfer into a syngeneic, naive host, HBsAg particle-pulsed DC, either freshly purified from skin or derived from a cloned DC line, efficiently primed class I-restricted, HBsAg-specific CTL precursors. M phi, either harvested from the peritoneal cavity or generated in macrophage-CSF-stimulated bone marrow cell cultures in vitro or derived from established, cloned M phi lines (PU5-1.8, J774A.1), pulsed with HBsAg particles in vivo or in vitro, elicited a class I-restricted, HBsAg-specific CTL response after adoptive transfer into naive hosts. The class I-restricted CTL response induced by HBsAg particle immunization was suppressed in carrageenan-treated mice, but was restored when carrageenan-treated mice were immunized with syngeneic, HBsAg-pulsed M phi. Selective elimination of M phi by liposome-incorporated dichloromethylene-diphosphonat did not suppress the induction of a CTL response of H-2d mice by HBsAg particle immunization. HBsAg-pulsed, freshly prepared DC are more potent than pulsed M phi in priming class I-restricted CTL in vivo. The relative importance of both types of APC in priming CTL remains to be resolved.

Impaired survival of T cell receptor V gamma 3+ cells in interleukin-4 transgenic mice.

The mouse epidermis contains a network of Thy-1+ dendritic T cells. Most of these cells express a homogeneous T cell receptor (TCR) configuration (V gamma 3/V delta 1) with only negligible junctional diversity. Because fetal thymocytes are precursors of these dendritic epidermal T cells (DETC) and the addition of interleukin (IL)-4 to fetal thymic organ cultures causes an early arrest in thymopoiesis, we examined DETC development in transgenic (tg) mice expressing IL-4 under the control of major histocompatibility complex class I regulatory sequences. Immunohistologic examination of epidermal sheets and polymerase chain reaction analysis of total skin RNA from IL-4 tg mice failed to reveal TCR V gamma 3+ DETC and V gamma 3 mRNA, respectively. In contrast, the sizes of TCR gamma delta subpopulations in lymphoid organs were unchanged in these mice. Although the numbers and staining intensities of TCR V gamma 3+ thymocytes in early fetal (days 14-17) IL-4 tg mice were similar to those of littermate controls, we observed a preferential death of these cells in thymic organ cultures from IL-4 tg mice. We observed further that epidermal sheets prepared from 9-day-old mice whose mothers had been treated with an IL-4-neutralizing antibody from day 12 to day 18 of pregnancy contained DETC numbers similar to those of controls. However, upon termination of the anti-IL-4 treatment, DETC ceased to expand. We conclude that IL-4 impairs the survival of TCR V gamma 3+ cells.

Autoantibodies to desmoplakin I and II in patients with erythema multiforme.

Erythema multiforme (EM) represents a syndrome of chronic recurrent inflammatory skin disease. Depending on the severity and extent of skin and mucosal involvement, it is defined either as EM minor or EM major. In this study we demonstrate the presence of autoantibodies (aAbs) against desmoplakin I and II, two major proteins of the desmosomal plaque, in six of six patients with the severe variant of EM, EM major. Light microscopic studies of lesional skin and mucous membranes localized in vivo bound immunoglobulin G (IgG) in a dotted desmosomal pattern along the cytoplasmic membranes of keratinocytes. By immunoelectronmicroscopy, in vivo bound IgG was confined to the desmosomal plaques. These findings were confirmed by indirect immunolocalization studies that demonstrated the presence of IgG aAbs in the serum of patients during active disease. These aAbs did not only bind to desmosomal plaques of epithelial cells where they colocalized with defined murine monoclonal antibodies directed against desmoplakin I and II, but also labeled the intercalated discs of myocardial cells. Biochemical characterization of circulating IgG aAbs revealed desmoplakin I and II as actual target autoantigens. By passive transfer of serum into newborn mice, in vivo binding of serum aAbs to keratinocytes was shown. The findings presented in this study imply a humoral immune response in certain patients with EM major and indicate a potential pathogenetic role of aAbs against desmoplakin I and II in this disease.

Dendritic cells as stimulator cells of MHC class I-restricted immune responses.

We have shown that growth factor-dependent, MHC class I+/II dendritic cell lines established from mouse fetal skin, can stimulate naive, allogeneic but not syngeneic CD8+ T cells in the absence of CD4+ T cells and that this T cell response is restricted by MHC class I molecules. We further showed that the FSCL-induced activation of naive CD8+ T cells is critically dependent on the physical contact between stimulator and responder cells and the expression of the costimulatory molecule B7 on FSCL. An important question that remains to be addressed concerns the derivation of FSCL. One could argue that they are members of the LC/DC family because they (i) exhibit certain features of fetal murine LC (i.e., CD45+, CD44+, CD32+, MHC class I+, MHC class II-, asialo GM1+, TCR-) including membrane-bound ADPase activity (A. Elbe, unpublished observation) and (ii) exhibit a pronounced dendritic configuration when cultured. If these cells are indeed derived from fetal LC, they should undergo the same phenotypic changes (MHC class II(-)-->MHC class II+) under in vitro culture conditions as do fetal LC in situ. However, our FSCL are phenotypically stable, and attempts to induce MHC class II expression with cytokine cocktails were unsuccessful. One explanation for this phenomenon could be that stimulatory signals provided by fetal keratinocytes or other skin cells are responsible for LC maturation in vivo and that, due to the early demise of these "stromal" cells in fetal skin cell cultures, the maturation process would not have been completed.(ABSTRACT TRUNCATED AT 250 WORDS)

Fetal skin-derived MHC class I+, MHC class II- dendritic cells stimulate MHC class I-restricted responses of unprimed CD8+ T cells.

Dendritic cells are very potent, if not the most effective, stimulator cells for the induction of primary T cell immune responses. We have established, from murine fetal skin, growth factor-dependent cell lines with a pronounced dendritic shape and a phenotype similar to that of fetal Langerhans cells (i.e., MHC class I+/II). Functionally, these lines induce a vigorous proliferation of allogeneic, but not syngeneic, CD8+ lymphocytes. T cell blasts thus generated are capable of lysing various target cells in an MHC class I-restricted fashion. Our contention that this skin cell-induced MHC class I-restricted activation of CD8+ lymphocytes occurs in the absence of CD4+ T cells is based on 1) the lack of FACS-detectable CD4+ T cells in the purified CD8+ T cell population, 2) the lack of reactivity of purified CD4+ T cells to MHC class I-disparate fetal skin cell lines, and 3) the inhibition of the fetal skin cell-induced MLR by anti-CD8/MHC class I, but not anti-CD4/MHC class II, mAb. Skin cell-induced activation of unprimed CD8+ T cells was found to be critically dependent on physical contact between stimulator and responder cells and the expression of the costimulatory molecule B7 on fetal skin cell lines. Lines described in this study may represent a powerful tool for studying the molecular events occurring in the induction of MHC class I-restricted primary immune responses, understanding their pathophysiologic role, and perhaps may prove useful for vaccination purposes against selected pathogens.

Identification and characterization of rat gamma/delta T lymphocytes in peripheral lymphoid organs, small intestine, and skin with a monoclonal antibody to a constant determinant of the gamma/delta T cell receptor.

A mAb called V65 was raised to a CD3+, TCR-alpha/beta- rat/mouse T cell hybrid that selectively reacts with all CD3+, TCR-alpha/beta- rat lymphocytes. Both anti-CD3 and V65 precipitate a 48- to 50-kDa heterodimeric protein from digitonin-lysed surface-iodinated cells. V65+ but not V65- T cells and T cell hybridoma cells express TCR-gamma mRNA. Together, these results show that V65 detects a constant determinant of the rat TCR-gamma/delta. In the presence of either IL-2 or IL-4, V65 stimulates proliferation in peripheral rat gamma/delta T cells. Approximately 90% of gamma/delta T cells from peripheral lymphoid organs have the same cell surface phenotype as thymus-derived MHC class I-restricted alpha/beta T cells, i.e., they are CD4- but express the CD8 alpha/beta heterodimer together with CD2 and CD5. In contrast, gamma/delta T cells from the epithelium of the small intestine lack CD2, CD4, and CD5 and express CD8 alpha only. Finally, V65 directly identifies a dense network of dendritic cells in the epidermis as gamma/delta T cells. These dendritic epidermal T cells are absent from athymic rats, indicating that like their mouse counterparts, they are thymus dependent.

T-cell receptor diversity in dendritic epidermal T cells in the rat.

The rat epidermis contains a population of dendritic CD3+ cells. For a better characterization of these cells and to investigate their relationship to epidermal lymphocytes of other species, we stained rat epidermal sheets using a variety of monoclonal antibodies against rat leukocyte differentiation antigens in an indirect immunofluorescence procedure. Additionally, we attempted to define their T-cell receptor (TCR) isotype at both the nucleic acid and protein level. Results obtained showed that the majority of the CD3+ dendritic epidermal cells are CD45+, CD2+, TCR alpha beta-, major histocompatibility complex class II-, Thy-1-, asialo GM1-, CD4-, CD5-, and CD8- lymphocytes. We further observed that, in contrast to the mouse system, the rat epidermis additionally harbors a small but distinctive portion of dendritic CD3+ cells that exhibit reactivity with an anti-pan TCR alpha beta monoclonal antibody. Our further finding that rat epidermal cells enriched for CD3+ lymphocytes express full-length C delta mRNA suggests that the vast majority of rat epidermal T cells carry surface-bound TCR gamma delta moieties. On the basis of these findings, one may speculate that the indigenous T-cell population of the epidermis is not necessarily programmed to uniformly express monomorphic TCR gamma delta molecules but, to effectively fulfill its role in host defense, is capable of adaptation to the specific challenges encountered by a given species.