Gender differences in presentation rates, deferrals and return behaviour among Norwegian blood donors.

BACKGROUND AND OBJECTIVES: Women are under-represented among long-term blood donors. Reasons for this were sought in the donor pool of the Blood Bank of Oslo, Norway, which comprises only voluntary, non-remunerated donors and has a high degree of stability. METHODS: Three sources of data were analyzed: (1) the subsequent six-year donation patterns of 17 812 donors who donated at least once in 1999; (2) reasons for pre-donation deferral of 484 prospect donors in 2004; (3) reasons for deferrals and absence during a 6.5-year period, retrieved from a follow-up study of 1029 donors who took part in a questionnaire study on motivation for blood donation in 2000. RESULTS: Women were over-represented among first-time donors and under-represented among regular donors. Women below the age of 45 years in 1999 were less likely than men to donate regularly throughout the 6-year study period, whereas the donation behaviour of women and men above 45 years of age was similar. Young (18-29 years) female prospect donors were more frequently deferred at first-time donation than males. In the 6.5-year follow-up study, pregnancy was the most frequently reported cause of absence from or termination of donation, and was reported by 32% of the female respondents that were 45 years or younger. Among the donors that reported having been pregnant, 42% stated to have resumed donation and < 4% stated that they no longer were blood donors. Reported termination of donation by female donors was associated with reported practical obstacles and discomfort related to donation, but not with loss of motivation. CONCLUSION: Most of the gender differences in donation patterns could be ascribed to absence because of pregnancy and lactation. Practical problems and discomfort during donation were important reasons why women reported to have stopped donation. Current deferral criteria pose problems for the recruitment and retention especially of young women.

Isolation of functionally active T cell receptor gamma delta-bearing lymphocytes from human peripheral blood.

We have developed a simple method for isolation of functionally active T cell receptor (TCR)-gamma delta positive cells from human peripheral blood, using immunomagnetic separation techniques. After culture with feeder cells and interleukin-2, cells thus isolated showed a CD3+ TCR-alpha beta- phenotype, and stained with antibodies against the TCR-gamma delta complex. The TCR-gamma delta+ cells were functionally active, responding with DNA synthesis when stimulated via their CD3 and CD2 molecules in concert, or when interleukin-2 was added.

Depletion of T lymphocytes from human bone marrow. Use of magnetic monosized polymer microspheres coated with T-lymphocyte-specific monoclonal antibodies.

A new technique for depletion of T cells from bone marrow is presented. Bone marrow cells (BMC) were rosetted with magnetic monosized polystyrene microspheres coated with monoclonal antibodies (MAbs) specific for T cell CD2 and CD3 antigens. Rosetted T cells were subsequently removed from non-T cells with the aid of a magnet. This immunomagnetic separation procedure was carried out in less than 40 min and reproducibly removed T cells, leaving a maximum of 0.025% sheep-red-blood-cell (SRBC) rosette-forming cells and less than 0.02% T cells as detected by a T cell limiting dilution assay. The efficacy of the depletion procedure was further shown by flow cytometry data, by effective removal of cells from a T cell line added to the BMC prior to immunomagnetic separation, and by abrogation of interleukin 2 (IL-2)-producing capacity in T-cell-depleted BMC (BMC-T). The T cell depletion procedure provided a 43-74% recovery of non-T cells present in the Isopaque-Ficoll-isolated bone marrow mononuclear cell fraction and did not disturb the growth potential of stem cells, as assayed by hematopoietic stem cell assays.

Susceptibility to develop celiac disease is primarily associated with HLA-DQ alleles.

We have recently reported that the susceptibility to develop celiac disease (CD) seems to be primarily associated to a particular combination of an HLA-DQA1 (DQA1*0501) and an HLA-DQB1 (DQB1*0201) allele: i.e., a particular DQ alpha/beta heterodimer. To investigate whether certain DP alleles might also contribute to the genetic susceptibility, DPA1 and DPB1 genes of 94 CD patients and 132 healthy controls were examined by probing in vitro amplified DNA with sequence-specific oligonucleotide probes corresponding to all hitherto known DPA1 and DPB1 alleles. The frequencies of the DPA1*0201 and of the DPB1*0101 alleles were increased in CD patients compared to healthy controls (0.31 versus 0.14 and 0.25 versus 0.08, respectively). However, these DP alleles were in linkage disequilibrium with CD-associated DQ alleles in the normal population, and the difference in frequency of these DP alleles was no longer significant when CD patients and healthy controls carrying the CD-associated DQA1*0501 and DQB1*0201 alleles were compared. DQB1*0201 homozygous individuals were overrepresented among DQB1*0201-positive patients compared to controls. When DQB1*0201 heterozygous patients and controls were compared, nearly identical frequencies of the DPA1*0201 and the DPB1*0101 alleles were found. Thus, the observed increase of the DPA1*0201 and DPB1*0101 alleles among CD patients seems mainly to be caused by linkage disequilibrium to the CD-associated DQ alleles.

Alterations in lymphocyte subsets in blood may predict resectability in carcinoma of cardia or oesophagus.

Impaired immune responses in patients with carcinoma of cardia or oesophagus have previously been reported. However, we do not know whether resectability correlates with specific immunological variables. Immunological assessment was performed in 35 such cancer patients including measurement of total T cells (CD3+) and T cell subsets (CD4+ and CD8+), NK cells (CD16+) and B cells (CD19+) in blood. In vitro lymphocyte responses to phytohemagglutinin (PHA) separated from peripheral blood were quantitated. The numbers in peripheral blood of both total T cells (CD3+) and B lymphocytes (CD19+) were significantly lower in the inoperable patients compared to resected patients (P < 0.01). The number of NK cells (CD16+) was, however, not significantly lower in the inoperable patients compared to the patients operated for cure. Lymphocyte responses to PHA in vitro were similar in resectable and non-resectable patients, but significantly lower in inoperable patients compared to the controls (P < 0.01). In conclusion, resectability in carcinoma of cardia or oesophagus is associated with changes in both T (CD3+) and B (CD19+) cell subsets.

Immunomagnetic separation of infiltrating T lymphocytes from brain tumors.

Tumor-infiltrating lymphocytes (TIL's) were isolated from human glioma biopsy specimens by immunomagnetic separation using T cell-specific monoclonal antibodies coupled to paramagnetic beads, and were expanded in culture with feeder cells and interleukin-2 (IL-2). The infiltrating cells from five of seven patients proliferated in culture. When tested after 2 to 3 weeks of culture, virtually all of the cells stained with antibodies against the CD2 and CD3 antigens. Most cells also expressed human leukocyte antigen class II molecules, while varying percentages of cells stained with antibodies against the IL-2 receptor and the CD4 and CD8 antigens. The cytotoxicity of the cultured TIL's against autologous and allogeneic glioma cells and the K562 and Daudi cell lines was measured and compared with that of lymphokine-activated killer (LAK) cells from the same patients. None of the TIL's showed significant cytotoxicity against these targets, whereas LAK cells lysed all of the targets.

C-reactive protein levels in the differential diagnosis of brain abscesses.

C-reactive protein (CRP) is a protein found in plasma at elevated concentrations during acute or chronic infections. As an aid in the differential diagnosis between brain tumor and abscess, the CRP levels were measured in 20 patients with intracranial mass lesions and the appearance of ring-like contrast enhancement on computerized tomography (CT) scans. In nine of these patients, the final diagnosis was abscess, based on either biopsy of the mass (eight patients) or the clinical course (one patient). In seven of the nine patients, there was a significant increase in CRP levels in two consecutive measurements. In particular, patients with cerebritis who were examined early in the course of the disease and who showed nonspecific CT scans exhibited extremely high levels of CRP. Two patients had no measurable CRP activity although they both had brain abscesses. In 12 patients harboring either gliomas or metastatic intracerebral tumors, CRP levels were significantly lower than those found in patients with brain abscesses but were nevertheless higher compared to those of a group of patients with benign tumors. It is concluded, therefore, that the measurement of CRP can have some value in the differential diagnosis between brain abscess and brain tumor. The measurement technique is inexpensive and is available in the clinical laboratories of most hospitals with a neurosurgical department.

Comparison of in vitro glioma cell cytotoxicity of LAK cells from glioma patients and healthy subjects.

Peripheral blood mononuclear cells from 11 glioma patients and 11 healthy control subjects were cultured in medium containing recombinant interleukin-2 for a period of 5 days. The cytotoxicity of these lymphokine-activated killer (LAK) cells was tested on chromium-51-labeled freshly prepared allogeneic glioblastoma cells, and on the cell lines K562 (natural killer cell (NK)-sensitive) and Daudi (NK-resistant). Peripheral blood mononuclear cells from all subjects showed high levels of cytotoxicity against these targets. There was no significant difference between the patients and the control group when LAK cytotoxicity was compared. Thus, although glioma patients are known to have depressed immunological reactivity, the cytotoxic capacity of LAK cells derived from glioma patients is similar to that of LAK cells from healthy control subjects. However, the glioma patients had significantly reduced numbers of mononuclear cells in their peripheral blood, possibly due to steroid treatment. Therefore, the volume of blood required to generate the same number of LAK cells was approximately three times larger from the glioma patients than from control subjects.

Levels of ochratoxin A in blood from Norwegian and Swedish blood donors and their possible correlation with food consumption.

Blood levels of ochratoxin A were determined in 406 Scandinavian blood donors (206 from Oslo, Norway, and 200 from Visby on the island of Gotland, Sweden), using an HPLC method. In connection with the blood collection, the subjects were asked to fill in a food questionnaire to obtain individual dietary information relevant to ochratoxin A exposure. The mean plasma level of ochratoxin A was 0.18 ng/ml in Oslo and slightly higher, 0.21 ng/ml (P=0.046) in Visby. There was no correlation between plasma levels of ochratoxin A and the estimated total dietary intake of ochratoxin A based on consumption data and levels in food (retrieved from the literature), neither was the plasma level of ochratoxin A correlated with the total amount of food consumed. However, consumption of several foods, including cereal products, wine, beer and pork, were to some minor degree related to high plasma levels of ochratoxin A. The strongest correlations (correlation coefficient r>0.4; P<0.001) were observed for women in relation to the consumption of beer or medium brown bread. Correlation analysis of combinations of two or more food categories did not result in any statistically significant correlation.

Recruiting and retaining young people as voluntary blood donors.

OBJECTIVES: Reasons for predonation deferral of young potential donors and prospects of recruiting and retaining young people (age 18-29) as voluntary blood donors were studied. STUDY DESIGN AND METHODS: Three different sources of data were analysed: (i) the subsequent donation history of 2057 donors who started their donation career at the Blood Bank of Oslo (BBO) in 1999, age and gender of all new donors accepted for donation at BBO in 2004 was retrieved from electronic data files; (ii) data on reasons for predonation deferral, age and gender of all deferred prospect donors at BBO in 2004 was obtained from original screening questionnaires; and (iii) results from a national telephone survey of the general population's attitudes regarding blood donation, conducted in 2005. RESULTS: Twenty-five per cent of the first-time donors recruited in 1999 remained active in 2005, but the percentage was higher among older than younger donors. Change of residency was the most frequent reason for termination of donation among young donors. Young prospect donors were more frequently than older ones deferred for lifestyle-related reasons. Prospect donors older than 30 years were more frequently deferred for health-related reasons. A large proportion (57.7%) of young adults reported a favourable attitude towards becoming blood donors. Lack of a personal request (not being asked) was the most frequently reported reason for not giving blood among young people with no donation record. Only a minor proportion of young non-donors considered themselves disqualified from donating blood due to health status. CONCLUSIONS: Lifestyle-related eligibility criteria and changes of residency pose problems for recruitment and retention of young donors. However, a large proportion of young adults state that they are able and willing to donate blood; therefore, the prospects of recruiting young people as voluntary blood donors seem generally positive.

Motivation, recruitment and retention of voluntary non-remunerated blood donors: a survey-based questionnaire study.

BACKGROUND AND OBJECTIVES: The aim of this study was to establish which motivational and socio-demographic factors are important for the development of a long-term commitment as a voluntary, non-remunerated blood donor. STUDY DESIGN AND METHODS: A cross-sectional sample survey of active blood donors in Oslo, Norway, was conducted. Donors filled in a self-administered questionnaire during donation. Data on motivation were analysed using factor analysis. RESULTS: The blood donors' socio-demographic characteristics were found to be similar to those of the population as a whole. The single, most important, recruitment channel was the influence of active blood donors. Five dimensions of blood-donor motivation were identified with factor analysis. These were: altruism and empathy; social reasons (such as the influence of friends and family); strengthening of one's self-esteem; positive experiences associated with donation; and a moral obligation to donate. Support for statements on altruistic motives for donation was strong and similar in long-time and short-time donors. In contrast, short-time donors were more likely to be motivated by factors related to self-esteem than were long-term donors. CONCLUSION: The 'good habit' of continued blood donation seems not to be exclusively linked to a high degree of reported other-regarding ('altruistic') reasons, but also to a combination of motives, including some modestly self-regarding motives.

Human interleukin-2 activated cytotoxic cells kill autologous glioma cells in vitro.

We have cultured peripheral blood lymphocytes (PBL) from glioblastoma patients in recombinant interleukin-2 (IL-2) containing medium for a period of 5 days. The cytotoxicity of these cells was tested on 51Cr-labelled autologous dissociated glioblastoma cells which had not been cultured. Significant cytotoxicity against glioma cells was observed in seven out of nine cases. IL-2 activated PBL from normal donors were equally cytotoxic against these glioma cells. Autologous lymphocytes activated by phytohaemagglutinin were also lysed in most cases, and the erythroleukemia cell line K562 was highly susceptible to the cytotoxic capability of the IL-2 activated PBL. In cold target inhibition experiments, K562 inhibited the cytotoxicity against both autologous and allogenic glioma cells, and glioma cells inhibited the cytotoxicity against K562. Following immunomagnetic separation, the IL-2 activated cells demonstrated cytotoxicity against glioma cells, K562 cells, and PHA blasts in both the CD8+ and the CD8- subsets.

T cell responses to a Dermatophagoides farinae allergen preparation in allergics and healthy controls.

We have studied possible differences between mite-allergic individuals and healthy controls in their T cell proliferation and T cell surface markers after in vitro stimulation with a Dermatophagoides farinae allergen preparation. No significant differences were found between the two groups in 3H-thymidine incorporation in T cells after 7 days in culture with allergen- and antigen-presenting cells. The frequencies of allergen-reactive T cells determined by limiting dilution were also similar in the two groups. Finally, no differences were found in surface markers on allergen-activated T cells from mite-allergic and healthy blood donors using a variety of monoclonal antibodies reactive with T cell subsets and activation antigens. Our conclusion is that with the D. farinae preparation employed in this investigation and using T cells prepared from peripheral blood no significant differences were seen between mite allergics and controls.

Cell-surface laminin-like molecules and alpha-D-galactopyranosyl end-groups of cloned strongly and weakly metastatic murine fibrosarcoma cells.

Indications from previous work that cancer cell-surface laminin-like molecules and alpha-D-galactopyranosyl end-groups may contribute to spontaneous metastasis were further investigated. Both moieties are known to mediate cell attachment to various foreign surfaces. Five strongly metastatic and 5 weakly metastatic cell clones from a murine fibrosarcoma were examined for the occurrence of both cell-surface moieties by immunofluorescence flow cytometry and microscopy. None of these clones was rich in laminin-like molecules, which were least strongly expressed by the highly metastatic clones. The alpha-D-galactopyranosyl end-groups were strongly expressed by all strongly metastatic clones and by 2 weakly metastatic clones, but were only weakly expressed by the other weakly metastatic clones. These results indicate that the laminin-like cell-surface molecules are not necessary for spontaneous metastasis formation. However, the alpha-D-galactopyranosyl end-groups may be necessary, but are not sufficient for the cancer cells to form metastases. These carbohydrates are known to occur on the laminin-like molecules. The present results show that they must also exist on other cell-surface molecules.

cis-Platinum as adjunctive to surgery in early stage ovarian carcinoma: effects on lymphoid cell subpopulations.

The effect of single-drug cis-diamminedichloroplatinum (CDDP) treatment on the distribution of T-lymphocyte subsets and monocytes was determined using monoclonal antibodies and a flow cytometry technique. Thirty-nine patients with radically operated ovarian carcinoma received postoperative treatment with six cycles of CDDP 50 mg/m2, and were examined either before, during, or after chemotherapy. During treatment, the number of OKT4+ (mainly T-helper) cells was reduced, whereas the number of OKT8+ (mainly T-suppressor/cytotoxic) cells was increased. Four to six months after the CDDP treatment was ended, these aberrations were no longer seen. The number of 1D5+ cells (monocytes) was not influenced by the treatment. It is concluded that no long-lasting change in the distribution of immunocompetent cells could be detected after this regimen of CDDP treatment.

Specificity of two subsets of cytotoxic human gamma delta T-cell clones.

Peripheral blood mononuclear cells were enriched for gamma delta T cells by immunomagnetic separation, stimulated with cells from an allogeneic donor, and cloned. T-lymphocyte clones (TLC) of the two major gamma delta T-cell subsets, BB3+ (i.e. V delta 2+) and delta TCS1+ (i.e. V delta 1/(D)/J delta 1), were obtained. In addition, one gamma delta TLC was BB3- delta TCS1-. All of the BB3+ TLC showed strong cytotoxicity against various allogeneic tumor cell lines, such as Daudi and K562. The cytotoxicity against the tumour cell lines was modulated by MoAb against the gamma delta TcR. The BB3+ TLC were not cytotoxic against B-lymphoblastoid cell lines (B-LCL). In contrast, the delta TCS1+ TLC showed much lower cytotoxic activity against the tumour cell lines, but many were strongly cytotoxic against allogeneic B-LCL. Some of the delta TCS1+ TLC demonstrated HLA-specific cytotoxicity, while other delta TCS1+ TLC had a more broad cytolytic activity against B-LCL. Thus, the two major subtypes of gamma delta T cells from this donor, as defined by MoAb BB3 and delta TCS1, were distinct with respect to recognition specificity.

Changes in lymphoid cell distribution after intraperitoneal administration of 32P colloids.

The effect of intraperitoneal administration of 32P colloids on the distribution of T lymphocyte subpopulations and monocytes was studied using monoclonal antibodies and a flow cytometry technique. Thirty-nine patients with ovarian carcinoma without residual tumor after primary operation were examined either before the administration of 260 to 370 MBq of 32P, 4 to 6 days after therapy, or 4 to 10 months after therapy. A significant reduction of circulating OKT4+ (T helper) cells occurred after therapy, and the reduction lasted throughout the observation period. Monocyte numbers were not significantly changed. It is concluded that intraperitoneal instillation of the 32P isotope may induce the same type of changes in circulating lymphoid cells as those seen after external field irradiation.

Human T lymphocyte clones: influence of culture conditions and optimization of proliferative assays.

Many CD4+ human T lymphocyte clones (TLC) are found not to proliferate against appropriate stimulating cells, and many lose this capacity during culture. This may be due, not to a defect in the recognition of the antigen, but to an inability to produce sufficient amounts of interleukin 2 (IL-2) for autocrine growth, since specific HLA-restricted proliferative responses could be induced in 'non-proliferative' clones by the addition of exogenous IL-2 or phorbol myristate acetate (PMA). Of various factors tested during expansion procedures of the clones, the proliferative capacity could only be restored by changing the stimulatory cells from B lymphoblastoid cell lines (B-LCL) to peripheral blood mononuclear cells (PBM). The cytotoxicity of the TLC was found to be independent of its proliferative capacity. After restoration of the proliferative capacity, a mouse B lymphoma cell line transfected with the appropriate HLA DQA and DQB genes was still not able to induce proliferation in the absence of exogenous IL-2. We conclude that (1) 'non-proliferative' TLC may recognize their targets, but fail to proliferate due to temporary lack of IL-2 production, and (2) even 'proliferative' T cells may fail to respond to certain target cells carrying the specific antigen, such as a murine transfectant, in the absence of exogenous IL-2.

Recognition of a particular HLA-DQ heterodimer by a human gamma/delta T cell clone.

Peripheral blood mononuclear cells from a single donor were depleted of T cell receptor (TcR) alpha/beta T cells, stimulated with allogeneic cells, and gamma/delta T lymphocyte clones (TLC) were isolated by limiting dilution. Five TLC were cytotoxic against B-lymphoblastoid cell lines from the stimulating cell donor, and demonstrated a restricted allospecificity in panel cell studies. One of these, gamma/delta TLC RNG-135, was studied in more detail. Its phenotype was CD3+ TcR alpha/beta - TcR gamma/delta + BB3- delta TCS1+ CD4- CD8-. Inhibition experiments using monoclonal antibodies indicated that the cytotoxicity of TLC RNG-135 was mediated through the TcR gamma/delta, and directed against an HLA-DQ molecule. In extended panel cell experiments, this gamma/delta TLC only lysed cells carrying the DQA1*0501 and DQB1*0301 genes, either in cis position (on the DR5, DQw7 haplotype), or in trans position (the donor of the stimulating cells, DR3,4; DQw2, w7). Thus, it appears that gamma/delta T cells may recognize a particular HLA-DQ alpha/beta heterodimer, which may be encoded by DQA1 and B1 genes both in cis and trans position.