[Detection and prevention in later life: risk profiles for physical, psychological, social and environmental frailty.] / Detectie en preventie van kwetsbaarheid: Op zoek naar risicoprofielen voor fysieke, psychische, sociale en omgevingskwetsbaarheid.

In order to provide proactive care and support for older people attention is needed for the prevention of frailty among older adults. Subsequently, accurate case finding of those who are more at risk of becoming frail is crucial to undertake specific preventive actions. This study investigates frailty and risk profiles of frailty among older people in order to support proactive detection. Hereby, frailty is conceived not only as a physical problem, but also refers to emotional, social, and environmental hazards. Using data generated from the Belgian Ageing Studies (N = 21,664 home-dwelling older people), a multinomial logistic regression model was tested which included socio-demographic and socio-economic indicators as well as the four dimensions of frailty (physical, social, psychological and environmental). Findings indicate that for both men and women having moved in the previous 10 years and having a lower household income are risk factors of becoming multidimensional frail. However, studying the different frailty domains, several risk profiles arise (e. g. marital status is important for psychological frailty), and gender-specific risk groups are detected (e. g. non-married men). This paper elaborates on practical implications and formulates a number of future research recommendations to tackle frailty in an ageing society.

"Here's my dilemma". Moral case deliberation as a platform for discussing everyday ethics in elderly care.

Our study presents an overview of the issues that were brought forward by participants of a moral case deliberation (MCD) project in two elderly care organizations. The overview was inductively derived from all case descriptions (N = 202) provided by participants of seven mixed MCD groups, consisting of care providers from various professional backgrounds, from nursing assistant to physician. The MCD groups were part of a larger MCD project within two care institutions (residential homes and nursing homes). Care providers are confronted with a wide variety of largely everyday ethical issues. We distinguished three main categories: 'resident's behavior', 'divergent perspectives on good care' and 'organizational context'. The overview can be used for agendasetting when institutions wish to stimulate reflection and deliberation. It is important that an agenda is constructed from the bottom-up and open to a variety of issues. In addition, organizing reflection and deliberation requires effort to identify moral questions in practice whilst at the same time maintaining the connection with the organizational context and existing communication structures. Once care providers are used to dealing with divergent perspectives, inviting different perspectives (e.g. family members) to take part in the deliberation, might help to identify and address ethical 'blind spots'.

Organizing moral case deliberation experiences in two Dutch nursing homes.

Moral case deliberation (MCD) is a specific form of clinical ethics, aiming to stimulate ethical reflection in daily practice in order to improve the quality of care. This article focuses on the implementation of MCD in nursing homes and the questions how and where to organize MCD. The purpose of this study was to evaluate one way of organizing MCD in two Dutch nursing homes. In both of these nursing homes the MCD groups had a heterogeneous composition and were organized apart from existing institutional communication structures. As part of a naturalistic evaluation, systematic observations, interviews and focus groups were completed. The findings indicate that the heterogeneous composition and MCD meetings separate from existing structures have benefits. However, the participants also reported negative experiences. This gives rise to the question whether a mixed MCD group which meets separately is an effective way to embed MCD as an instrument for reflection on moral issues in daily practice. We conclude that there is no single answer to that question. In the end, the two implementation strategies (i.e. within existing communication structures and a mixed MCD group) can be complementary to each other.

Identification of acceptable HLA mismatches in immunized patients using single-antigen-expressing cell lines.

Sera of highly sensitized patients (HSP) contain complex human leukocyte antigen (HLA) antibodies, minimizing the chance to identify crossmatch-negative donors. Expression of 3-6 HLA class I antigens on lymphocytes hampers identification of acceptable mismatches (AMs) by conventional screening (C-SCR). The single-antigen-expressing cell line (SAL) concept circumvents this problem. As a proof of principle, 26 sera of sensitized patients were tested by flow cytometry for immunoglobulin G antibodies against 16 HLA-A and -B SALs. Results were compared with C-SCR. Mostly, SAL reactions confirmed presence/absence of HLA antibodies. While C-SCR sometimes failed to provide unambiguous antibody specificity, we defined 24 new HLA antibody specificities with SALs and proposed 33 new AM by non-reactivity with SALs. Thus, the SAL concept is useful for confirmation/identification of AM and will enhance transplantation of HSP.

Homing of human autoreactive T cells into pancreatic tissue of NOD-scid mice.

AIMS/HYPOTHESIS: An important prerequisite for the initiation of pancreatic islet inflammation is the recruitment of pathogenic T cells. We investigated the in vivo migration patterns of human islet-reactive T cell clones after transfer into compromised hosts. METHODS: NOD-scid mice were injected with a mixture of human autoreactive T cells and antigen-presenting cells. Survival and migration of T cells was analysed by fluorescence-activated cell sorter and immunohistochemical analysis of various tissues. RESULTS: Autoreactive T cells and antigen-presenting cells survived at least 14 days in vivo and accumulated in spleen, pancreatic tissue and pancreas draining lymph nodes, but not elsewhere, as early as 4 days after transfer. This homing was dependent on co-injection of human antigen-presenting cells loaded with autoantigen. Finally, we found that this process is enhanced by streptozotocin treatment. Streptozotocin treatment did not affect the constitutive homing to pancreas draining lymph nodes. Histological analysis of pancreatic tissue sections showed some autoreactive T cells around the islets of Langerhans, comparable to early peri-islet insulitis. However, the majority of pancreas-infiltrating T cells accumulated around blood vessels in the exocrine pancreas. All T cell clones expressed the chemokine receptor CXCR3 that is associated with homing to insulitic lesions in men and mice. CONCLUSIONS/INTERPRETATION: Our study provides the first evidence of in vivo accumulation in pancreatic tissue of islet-reactive T cells derived from type 1 diabetic patients. The fact that such T cells do not penetrate islets is in line with the concept that additional factors may be required for the entry of T cells into inflamed islets to become diabetogenic.

Determination of the frequency of HLA antibody secreting B-lymphocytes in alloantigen sensitized individuals.

Sera from prospective transplant patients are usually screened for HLA antibodies prior to transplantation, but presently available tests do not permit quantification of the humoral alloantigen directed response. We adapted a culture system for isolated human B-lymphocytes to assay the secretion of HLA-antibodies on a single cell basis. B-cell supernatants were screened for HLA antibodies by complement dependent cytotoxicity. The assay assigns precursor frequencies for HLA-alloantibody secreting B-lymphocytes (BCPFs), and simultaneously allows for dissection of the humoral alloantigen directed response into its monoclonal components. The lymphocytes of 15 HLA-seropositive multiparous women that were used to validate the assay, were found to contain HLA-BCPFs ranging from 0 to 123 per 10(6) B-lymphocytes (mean: 43 +/- 45 per 10(6) B-lymphocytes). The HLA-specificities of antibodies in the B-cell supernatants were in agreement with serum specificities. Genuine HLA reactivity of B-cell supernatants was confirmed using an ELISA with purified HLA class I antigens. When applied to lymphocytes of patients on transplant waiting lists, the present assay may enable the unraveling of serum specificities in their components, thus supplementing HLA antibody serum screening data.

Caring for the elderly without residential care homes and nursing homes.

For decades, intramural care of infirm elderly persons in the Netherlands has been classified into caring for them in residential care homes and nursing homes. Over the past five to ten years, the composition of the population of elderly persons has been subject to change, particularly of those in residential care homes. Organisations and institutions providing care for the elderly are going through turbulent times. All kinds of partnerships between residential care and nursing homes are being entered into. Intramural organisations providing care and nursing will have to respond to the integration of caring and nursing functions. Based on a pilot study into the need for care and support among the elderly in residential care and nursing homes, the author proposes a structure in which the first echelon consists of home care, the second of care centres and the third of geriatric centres where mainly cure oriented care is provided.

A human monoclonal antibody against HLA-Cw1 and a human monoclonal antibody against an HLA-A locus determinant derived from a single uniparous female.

Two human monoclonal antibodies (HuMAbs) with widely different HLA specificities were raised from a uniparous HLA-seropositive female. Screening against a large panel of serologically HLA-typed lymphocytes in the complement-dependent cytotoxicity test showed that one of these HuMAbs, VP6G3, was specific for HLA-Cw1, thereby constituting the first HuMAb against an HLA-C locus product. The second HuMAb, VP5G3, was directed against an HLA-A-encoded determinant shared by HLA-A11, -A25, -A26 and -A66. The epitopes responsible for binding were determined by comparing the aminoacid sequences and were pinpointed to the 6K/9F combination for HuMAb VP6G3, and 163R with a critical contribution of aminoacids present at positions 166/167 for HuMAb VP5G3.

Reactivity of twenty-two cytotoxic human monoclonal HLA antibodies towards soluble HLA class I in an enzyme-linked immunosorbent assay (PRA-STAT).

An ELISA, PRA-STAT was recently introduced for the detection of HLA class I specific antibodies of IgG isotype in patients' sera. We studied the antigenicity of the soluble HLA (sHLA) preparations that are used in this ELISA as the detection matrix, with the aid of a panel of complement binding human HLA monoclonal antibodies (HuMAbs). A total of 22 HuMAbs, including both IgG and IgM were used. CDC and PRA-STAT ELISA were in complete agreement on 9 of the mAbs tested, with 16 HLA-A and 16 HLA-B locus antigens or their splits identified identically on CDC and PRA-STAT. In 7 of the remaining 13 HuMAbs, there was a difference of one antigen in the specificity pattern of the two techniques three times a specificity call not made by CDC, and four times a call not made by PRA-STAT. For the remaining 6 HuMAbs the differences involve 2 antigens (4 HuMAbs), and 3 or 4 antigens (1 HuMAb each). This study shows the validity of PRA-STAT for detection of HLA-class I antibodies, irrespective of isotype, in serum. The immunological integrity of the sHLA preparations used in PRA-STAT is also confirmed, albeit with some slight discrepancies in antibody specificity seen between PRA-STAT and CDC.

The relative radioresistance of interleukin-2 production by human peripheral blood lymphocytes: consequences for the development of a new limiting dilution assay for the enumeration of helper T lymphocyte precursor frequencies.

We describe a limiting dilution assay for the enumeration of alloreactive helper T lymphocyte precursor frequencies in human peripheral blood. The proliferation rate of the murine indicator cell line, cytotoxic T lymphoblastic line 2 (CTLL-2) induced by interleukin-2 (IL-2) culture supernatants was determined by staining with the fluorescent DNA dye propidium-iodide. Lymphocytes from healthy individuals as well as from patients with end stage kidney disease and no previous allosensitization exhibited a relative radioresistance of their IL-2 production up to gamma irradiation doses of 40-60 Gy. This differs from previous findings in the literature, showing a total inhibition of the IL-2 production in unsensitized individuals using a gamma irradiation dose of 20 Gy. The consequences of this relative radioresistance are that for a reliable stimulator cell inactivation in assays for the enumeration of helper T lymphocyte precursors gamma irradiation doses of at least 50 (-60) Gy are needed. Increasing the gamma irradiation dose for the inactivation of the stimulator cells can result in a decrease of the antigen presenting capacity of these cells.

A human monoclonal antibody, produced following in vitro immunization, recognizing an epitope shared by HLA-A2 subtypes and HLA-A28.

In vitro immunization and subsequent immortalization of peripheral blood cells of a multiparous woman has resulted in the production of a stable human mouse heterohybridoma, 5C2A2, secreting an HLA-A2/A28-specific human monoclonal antibody. Although possibly exposed to HLA-A2 by transfusions, the cell donor showed no HLA-A2-specific serum antibodies. The present protocol for in vitro immunization includes the elimination of suppressor cells from the responder cell population, the presence of irradiated allogeneic lymphocytes as a source of antigen, as well as stimuli--recombinant interleukin-2 and a B-cell specific nucleoside analogue--causing the proliferation of B lymphocytes, prior to immortalization. The ability of the antibody 5C2A2 to detect all known HLA-A2 subtypes, except A2.3, and A28, allows identification of the serological epitope on the HLA-A2 molecule. Application of this in vitro immunization method allows the production of a set of HLA monoclonal antibody-secreting human hybridomas, independent of the existence of serum HLA antibodies in the lymphocyte donors.

Characterization of two human monoclonal antibodies reactive with HLA-B12 and HLA-B60, respectively, raised by in vitro secondary immunization of peripheral blood lymphocytes.

We have developed an in vitro immunization system for the production of B-cell lines that secrete HLA-specific human mAbs. For this purpose, peripheral blood lymphocytes of parous women were stimulated with pools of allogeneic lymphocytes. Preferential outgrowth of B-lymphocytes was effected by inclusion of rIL-2 and a B-cell specific nucleoside analogue. Stimulated B cells were immortalized by EBV transformation, and specific antibody-producing transformants were fused to heteromyeloma or mouse myeloma cell lines, yielding stable hybridomas. This approach has led to the successful development of two human heterohybridomas producing HLA-specific mAbs reactive by complement-mediated cytotoxicity. The specificities of these human mAbs, reactive with HLA-B12(44 + 45) and HLA-B60, respectively, are fully concordant with those of HLA-typing sera.

The influence of cytomegalovirus carrier status on lymphocyte subsets and natural immunity.

The influence of the cytomegalovirus (CMV) carrier status on peripheral lymphocyte subsets was studied in 70 healthy individuals. IgG-class antibodies against CMV late antigen were used as markers for the presence of CMV in those individuals. The 39 CMV-seropositive individuals had significantly higher numbers of CD3+ (P = 0.009), CD8+ (P = 0.005) and HNK1+ (P = 0.002) cells than the 31 CMV-seronegative individuals. Two-colour immunofluorescence studies revealed that the HNK1+ cells coexpressing CD4 or high density CD8 were particularly increased in the number under the influence of CMV, but not the HNK1+ cells coexpressing CD16. Since HNK1 and CD16 are markers associated with natural killer (NK) activity and antibody-dependent cellular cytotoxicity (ADCC), we investigated the influence of the CMV carrier status on those functions. The NK and ADCC functions of peripheral blood mononuclear cells (PBMC), HNK1+ and HNK1- cells were correlated with the percentages of CD16+ cells among those cells. Although CMV-seropositive individuals had significantly less CD16+ cells among their HNK1+ cells than CMV-seronegative individuals (mean and s.d.: 39 and 19%, versus 58 and 11%, P = 0.003), the NK and ADCC functions of the HNK1+ cells were similar in both groups. Also, the CMV carrier status did not influence significantly those functions of PBMC and HNK1- cells. We conclude that the CMV carrier status, i.e. CMV-seropositivity, is associated with a significant increase in the numbers of HNK1+ lymphocytes coexpressing T cell markers. That situation may reflect the continuing interaction between CMV and the immune system of its host.

Antibody dependent cellular cytotoxicity mediated by HLA-class II specific monoclonal antibodies.

The ability of mouse monoclonal antibodies (MoAbs) directed against HLA-class II molecules to mediate in Antibody Dependent Cellular Cytotoxicity (ADCC) was investigated. The results indicate that both MoAbs to monomorphic and polymorphic HLA-DR and DQ determinants are able to mediate ADCC in an antigen specific manner. However, not all antibodies mediate ADCC to a similar extent. Furthermore, antibodies were identified that appeared to mediate ADCC in an HLA-DR haplotype dependent fashion. These results indicate that the inhibition of HLA-class II specific proliferative responses by anti-class II MoAbs may be influenced by ADCC directed against class II positive stimulator cells.

Automated reading of HLA-A,B,C typing and screening. The propidium iodide (PI) method.

A routine method has been developed and tested in the laboratory for the automatic reading of HLA typing and screening for antibodies with the microlymphocytotoxicity test. The assay is more sensitive than the NIH technique, is rapid, produces objective results, and can be easily linked up with existing manual procedures. Multipurpose reading machines are now commercially available.