Proceedings of the 2023 Second Annual ASTCT-NMDP ACCESS Initiative Workshop

Here the proceedings from the Second Annual American Society for Transplantation and Cellular Therapy (ASTCT) and National Marrow Donor Program (NMDP) ACCESS Initiative are reviewed to inform the hematopoietic cell transplantation (HCT) and cellular therapy (CT) ecosystem about progress and direction of the collaborative. Highlights from the meeting, including updates on the progress of projects from the Awareness, Poverty, and Racial Inequity Committees, are presented. The ACCESS Initiative continues to evolve and will remain dependent on the HCT/CT ecosystem's continued dedication to reduce barriers and improve outcome disparities for all patients in need of HCT/CT.

Abstract WP334: American Indian Participation in Clinical Research: A Cultural Perspective Survey from a CREST-2 Site

Introduction: Participation by American Indian and Alaska Natives (AI/AN) in clinical research may improve AI/AN health outcomes and generalizability of the research.

Hypothesis: Cultural beliefs have a strong impact on willingness of AI/AN to participate in research.

Methods: We developed a survey to identify if cultural beliefs impact perception of clinical research and the Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial (CREST-2) protocol. Stroke neurologists and CREST-2 investigators participated in the design of the survey. Participants were stratified based on AI/AN self-identification and level of education. Likert-scale responses were tested with the Mann Whitney-U test and dichotomous responses with the Chi-Square test.

Results: There were 102 participants: 61% female, mean age 39, and 37% AI/AN. Eight questions evaluated understanding of research concepts within CREST-2; 89% of these responses were correct, with no significant difference in responses between AI/AN and non-AI/AN or between low (n=42) and high (n=60) education. Compared to other ethnic groups, AI/AN identify more with their culture (p=0.002) and consider cultural beliefs when making health care decisions (p=0.005), including participating in a research study (p=0.002). Using the same questions, we found no difference between respondents with low or high education.(Figure 1)

Conclusion: These data support our hypothesis that cultural beliefs have a strong impact on AI/AN willingness to participate in research. It is important for researchers to consider cultural beliefs when designing recruitment strategies for AI/AN populations. Future work will address how cultural beliefs affect AI/ANs’ understanding of and willingness to participate in clinical research.

The genetic basis of colorectal cancer in a population-based incident cohort with a high rate of familial disease

BACKGROUND AND AIMS

Colorectal cancer (CRC) is the second most frequent cancer in developed countries. Newfoundland has the highest incidence of CRC in Canada and the highest rate of familial CRC yet reported in the world. To determine the impact of mutations in known CRC susceptibility genes and the contribution of the known pathways to the development of hereditary CRC, an incident cohort of 750 patients with CRC (708 different families) from the Newfoundland population was studied.

METHODS

Microsatellite instability (MSI) testing was performed on tumours, together with immunohistochemistry analysis for mismatch repair (MMR) genes. Where indicated, DNA sequencing and multiplex ligation-dependent probe amplifications of MMR genes and APC was undertaken. DNA from all patients was screened for MUTYH mutations. The presence of the BRAF variant, p.V600E, and of MLH1 promoter methylation was also tested in tumours.

RESULTS

4.6% of patients fulfilled the Amsterdam criteria (AC), and an additional 44.6% fulfilled the revised Bethesda criteria. MSI-high (MSI-H) was observed in 10.7% (n=78) of 732 tumours. In 3.6% (n=27) of patients, CRC was attributed to 12 different inherited mutations in six known CRC-related genes associated with chromosomal instability or MSI pathways. Seven patients (0.9%) carried a mutation in APC or biallelic mutations in MUTYH. Of 20 patients (2.7%) with mutations in MMR genes, 14 (70%) had one of two MSH2 founder mutations. 17 of 28 (61%) AC families did not have a genetic cause identified, of which 15 kindreds fulfilled the criteria for familial CRC type X (FCCTX).

CONCLUSIONS

Founder mutations accounted for only 2.1% of cases and this was insufficient to explain the high rate of familial CRC. Many of the families classified as FCCTX may have highly penetrant mutations segregating in a Mendelian-like manner. These families will be important for identifying additional CRC susceptibility loci.

A novel bile duct cannulation method with tail cuff exteriorization allowing continuous intravenous infusion and enterohepatic recirculation in the unrestrained rat

A variety of bile duct cannulation methods have been used in the study of biliary excretion in the rat. We now report the validation and use of one such method. In this method, the common bile duct and duodenum were cannulated, the free ends of the cannulae tunnelled through the abdominal wall, passed through a trochar and exteriorized at the ventral aspect of the tail. A purpose-designed stainless steel tail cuff was then attached, to protect the cannulae from the rat. The cannulae were passed through the top of a metabolism cage and attached to a dual swivel that allows the rat freedom of movement within the metabolism cage. Where necessary an additional cannula could be placed in the femoral vein to allow infusion of test material or blood sampling. The results demonstrate that the method is robust and that its use allows a reliable correlation between surgically prepared and intact animals, as physiological parameters are allowed to return to normal prior to inclusion of the animals in the study. The technique allows the animals a great deal of freedom and, as such, is considered to minimize stress associated with the procedure. This fact is reflected in the reliability and reproducibility of the data obtained over the wide range of studies that have been conducted using this method. This method has been in use for over 4 years at Inveresk and this paper describes the authors' experience with the method to date.

Continuous intravenous infusion in athymic (nude) rats: an animal model for evaluating the efficacy of anti-cancer agents

The athymic (nude) rat (rnu/rnu) has been used for a number of years in research into various human tumours involving xenotransplantation. We now report the validation of a continuous intravenous infusion method in nude rats using a tail cuff tether, which enables the study of the efficacy of novel anti-cancer materials in this mutant strain, using intravenous infusion and with no restriction of the animals or of the tumour implantation sites by jackets. Ten animals each had a cannula surgically implanted into the vena cava via the femoral vein and exteriorized via a tail cuff. Animals were housed singly in conventional cages following surgery. Following a recovery period of 5 days all animals were continuously infused with physiological saline at an infusion rate of 0.5 ml/h for a further 37 days. Body weights and food consumption were recorded weekly. Blood samples were taken approximately 14 days post-surgery and analysed for haematology and clinical chemistry parameters. All animals were successfully cannulated, and no unexpected adverse clinical signs were noted during the recovery period and the 37 days of infusion. The results demonstrate that it is possible to surgically cannulate the femoral vein of athymic (nude) rats and infuse them in conventional cages for a period of up to 37 days with minimal adverse effects. The minimal restraint required provides benefits both to the animal and to the conduct of studies such as assessment of tumour growth in the absence of a jacket. Recent work has demonstrated that the same techniques can be successfully applied to the nude mouse.

Discordant P-glycoprotein antigen expression and transport function in acute myeloid leukemia

Expression of the multidrug resistance efflux pump P-glycoprotein (Pgp) was measured in a series of AML patients using two flow cytometry methods. Transport function was assessed by measuring the modulating effect of the Pgp inhibitor cyclosporin A (CsA) on the cellular accumulation of daunorubicin, and Pgp antigen expression by surface immunofluorescence using the MRK-16 antibody. Both methods showed a wide range of values for Pgp expression between individual patients, but in contrast to a series of cell lines expressing Pgp there was no correlation between antigen expression and transport function in the clinical samples. As previously reported for chronic lymphocytic leukemia (CLL), pretreatment with neuraminidase markedly improved MRK-16 staining in some cases, indicating that abnormal glycosylation can cause epitope masking in AML blasts. Because experience with cell lines shows that Pgp expression is a continuous variable which correlates with the level of drug resistance, rather than the 'positive' or 'negative' which are frequently reported by clinical flow cytometry laboratories, we used a calibration procedure to estimate the actual number of Pgp molecules expressed in the AML samples. Despite the additional refinements of neuraminidase treatment and antigen quantification, the correlation between Pgp antigen expression and daunorubicin accumulation remained extremely weak (r = 0.11; P = 0.63). It is suggested that the assay for transport function can detect molecules that affect daunorubicin accumulation but are antigenically distinct from classical P-glycoprotein. Heterogeneity of multidrug resistance efflux pumps might in part explain the relatively weak prognostic significance of immunofluorescence detection of Pgp in AML patients.

Typing for major histocompatibility complex class II antigens in thyroid tissue blocks: association of Hashimoto's thyroiditis with HLA-DQA0301 and DQB0201 alleles

This study was undertaken 1) to find out whether we can type major histocompatibility class II antigens from the paraffin-embedded series of thyroid tissue, and 2) to investigate whether HLA-DQ genes are involved in conferring a risk of Hashimoto's thyroiditis. To this end we used the polymerase chain reaction to amplify DNA from paraffin-embedded thyroid tissue blocks of histologically proven Hashimoto's disease. We used 46 specimens for HLA-DQA and 32 for DQB typing. The alleles were identified by sequence-specific oligonucleotide hybridizations. Fifty controls from the same geographic region were also typed using peripheral leukocyte DNA. HLA-DQA0301 (in linkage disequilibrium with DR4) was significantly increased (58.7% vs. 32% in controls; chi 2 = 6.73; P less than 0.01) in patients compared to controls. DQB0201 (in linkage disequilibrium with DR3) was also increased in the patient group (66% vs. 36% in controls; chi 2 = 6.63; P less than 0.01). Although DQA0301/DQB0201 heterozygotes (18.8%) were increased in patients compared to controls (6%), the difference was not significant. However, 81% of the patients (26 of 32) were DQA0301 and/or DQB0201 positive compared to 48% of controls (chi 2 5.98; P less than 0.05). We conclude that it is feasible to type HLA antigens from tissue blocks and that susceptibility to Hashimoto's disease is probably mediated through two pathways: DQA0301/DR4 and DQB0201/DR3.

Costs of primary health care at the Alexandra Health Centre

This study provides a detailed analysis of costs and expenditure patterns at a primary health care centre serving an impoverished community of about 200,000 people. Data were collected on costs and utilisation of services at the Alexandra Health Centre and University Clinic (AHC) for the financial year ending March 1990. Capital and running costs were kept separate. The sources of data collection were statistics routinely collected in the different sections of the clinic, the accounting records, staff duty rosters and a prospective study done to collect information to apportion drug costs and to calculate the cost of a prescription. The audited operating expenditure at AHC for the 1990 financial year was R3.9 million, or R4,45 million with donations (mainly drugs and staff). Sixty-three per cent of total costs went on staff, 16% on drugs and supplies, 9% on buildings, furniture and transport, 3% on laboratory services, 2% on security and 8% on other items. The outpatients department accounted for 57% of expenditure, the 24-hour unit 37% and the outreach section 6%. Looked at another way, 66% went on curative services, 32% on preventive and promotive (including 13% on maternity costs) services, and 2% on rehabilitation services. The average cost per visit to each of 14 services is presented. The cost of a visit to casualty is R38.85, to the antenatal clinic R18.65 and to the child health outreach programme for immunisation R6.67. The component costs of each visit are analysed. The major cost component of a consultation is usually clinical staff, and detailed staff allocations for each section are given.(ABSTRACT TRUNCATED AT 250 WORDS)

Developing a health information system for a primary health care centre in Alexandra, Johannesburg

The development of a health information system, which went through 6 overlapping phases, appropriate for a primary health care centre at the Alexandra Health Centre and University Clinic (AHC) is reviewed. The three essential concepts were data, information and indicators. The system at the AHC moved from unused data to unused information and to operational indicators. It also moved from a concern with data and information to one concerned with communication of information. The way a health information system evolves is, to a large extent, a reflection of the information needed by the group that is planning the system. In the AHC information needs were initially felt by senior management and attempts to involve other staff failed because of lack of timely feedback and a lack of management skills at all levels. In the process of trying to involve people and of getting to the correct type and amount of information, it became obvious that a health information system is complex and involves data as the major outputs, with people being the common thread of the system.

A profile of Alexandra

In this article publications on the demography and environmental and health status of Alexandra Township are reviewed and a demographic survey carried out in 1990 is reported. The demographic data presented in the article describe the age, sex and ethnic profile of the population. It also describes the health and disease status, provides some vital statistics, describes the health services and discusses the implications for the development of appropriate health care strategies. Approximately 19% of the population live in informal dwellings or shelters, 14% in the newly upgraded areas and 67% in old Alexandra. Mean household occupancy was 4.04 with a male/female (m/f) ratio of 0.86. It was 3.08 in informal dwellings (m/f = 1.11), 4.30 in the newly upgraded areas (m/f = 0.74) and 4.28 for Old Alex (m/f = 0.82). Old Alex had the highest proportion of inhabitants aged over 60 years. On average females have been resident in Alexandra for 16.8 years and males for 14.9 years.

High rates of ras codon 61 mutation in thyroid tumors in an iodide-deficient area

Using polymerase chain reaction and sequence-specific oligonucleotide hybridization, the frequency of three ras oncogene mutations (N-ras, Ha-ras, and K-ras) in thyroid tumors (25 adenomas, 16 follicular carcinomas, and 22 papillary carcinomas) was investigated in both iodide-deficient and iodide-sufficient areas. The ras oncogene mutation rate was significantly higher in the iodide-deficient area, being 85 versus 17% in the adenomas, and 50 versus 10% in the follicular carcinomas. No mutations were found in papillary carcinomas. The most common mutation site was Ha-ras codon 61 with Gln----Arg substitution. Two ras mutations at codon 61 (Gln----Lys in N-ras and Gln----Arg in Ha-ras) were found in a microfollicular adenoma specimen from Eastern Hungary. We conclude that dietary iodine may modulate ras oncogene mutations, and that in the iodide-deficient area, ras oncogene activation may play a more important role in the initiation and/or maintenance of follicular tumors. Additional factors are, however, necessary to initiate carcinogenesis.

Radiation dose and breast cancer risk in patients treated for cancer of the cervix

The relationship between breast cancer and radiation treatment for cervical cancer was evaluated in an international study of 953 women who subsequently developed breast cancer and 1,806 matched controls. Radiation doses to the breast (average 0.31 Gy) and ovaries (average 32 Gy) were reconstructed for exposed subjects on the basis of their original radiotherapy records. Overall, 88% of the breast cancer cases and 89% of the controls received radiation treatment [relative risk (RR) = 0.88; 95% confidence interval (CI) = 0.7-1.2]. Among women with intact ovaries (561 cases, 1,037 controls), radiotherapy was linked to a significant 35% reduction in breast cancer risk, attributable in all likelihood to the cessation of ovarian function. Ovarian doses of 6 Gy were sufficient to reduce breast cancer risk but larger doses did not reduce risk further. This saturation-type response is probably due to the killing of a critical number of ovarian cells. Cervical cancer patients without ovaries (145 cases, 284 controls) were analyzed separately because such women are at especially low natural risk for breast cancer development. In theory, any effect of low-dose breast exposure, received incidentally during treatment for cervical cancer, should be more readily detectable. Among women without ovaries, there was a slight increase in breast cancer risk (RR = 1.07; 95% CI = 0.6-2.0), and a suggestion of a dose response with the RR being 1.0, 0.7, 1.5 and 3.1 for breast doses of 0, 0.01-0.24, 0.25-0.49 and 0.50+ Gy, respectively. However, this trend of increasing RR was not statistically significant. If low-dose radiation increases the risk of breast cancer among women over age 40 years, it appears that the risk is much lower than would be predicted from studies of younger women exposed to higher doses.

Radiation dose and second cancer risk in patients treated for cancer of the cervix

The risk of cancer associated with a broad range of organ doses was estimated in an international study of women with cervical cancer. Among 150,000 patients reported to one of 19 population-based cancer registries or treated in any of 20 oncology clinics, 4188 women with second cancers and 6880 matched controls were selected for detailed study. Radiation doses for selected organs were reconstructed for each patient on the basis of her original radiotherapy records. Very high doses, on the order of several hundred gray, were found to increase the risk of cancers of the bladder [relative risk (RR) = 4.0], rectum (RR = 1.8), vagina (RR = 2.7), and possibly bone (RR = 1.3), uterine corpus (RR = 1.3), cecum (RR = 1.5), and non-Hodgkin's lymphoma (RR = 2.5). For all female genital cancers taken together, a sharp dose-response gradient was observed, reaching fivefold for doses more than 150 Gy. Several gray increased the risk of stomach cancer (RR = 2.1) and leukemia (RR = 2.0). Although cancer of the pancreas was elevated, there was no evidence of a dose-dependent risk. Cancer of the kidney was significantly increased among 15-year survivors. A nonsignificant twofold risk of radiogenic thyroid cancer was observed following an average dose of only 0.11 Gy. Breast cancer was not increased overall, despite an average dose of 0.31 Gy and 953 cases available for evaluation (RR = 0.9); there was, however, a weak suggestion of a dose response among women whose ovaries had been surgically removed. Doses greater than 6 Gy to the ovaries reduced breast cancer risk by 44%. A significant deficit of ovarian cancer was observed within 5 years of radiotherapy; in contrast, a dose response was suggested among 10-year survivors. Radiation was not found to increase the overall risk of cancers of the small intestine, colon, ovary, vulva, connective tissue, breast, Hodgkin's disease, multiple myeloma, or chronic lymphocytic leukemia. For most cancers associated with radiation, risks were highest among long-term survivors and appeared concentrated among women irradiated at relatively younger ages.

Fetal glycaemic control and neonatal complications in diabetic pregnancy

To examine the relationship between fetal glycaemic control and macrosomia or neonatal hypoglycaemia, we measured umbilical cord glycosylated haemoglobin (GHb) by affinity chromatography in 44 diabetic and 40 normal pregnancies. Levels of GHb in cord blood were not significantly different between these two groups, suggesting good maternal glycaemic control was achieved in the diabetic patients. Moreover in the diabetic pregnancies, cord GHb levels did not differ in infants who were macrosomic or developed hypoglycaemia by comparison with those infants who showed neither phenomenon. We conclude that overall fetal glycaemic control in the 4-6 week period prior to delivery does not appear to influence these common neonatal complications of diabetic pregnancy.

Radiation dose and leukemia risk in patients treated for cancer of the cervix

To quantify the risk of radiation-induced leukemia and provide further information on the nature of the relationship between dose and response, a case-control study was undertaken in a cohort of over 150,000 women with invasive cancer of the uterine cervix. The cases either were reported to one of 17 population-based cancer registries or were treated in any of 16 oncologic clinics in Canada, Europe, and the United States. Four controls were individually matched to each of 195 cases of leukemia on the basis of age and calendar year when diagnosed with cervical cancer and survival time. Leukemia diagnoses were verified by one hematologist. Radiation dose to active bone marrow was estimated by medical physicists on the basis of the original radiotherapy records of study subjects. The risk of chronic lymphocytic leukemia, one of the few malignancies without evidence for an association with ionizing radiation, was not increased [relative risk (RR) = 1.03; n = 52]. However, for all other forms of leukemia taken together (n = 143), a twofold risk was evident (RR = 2.0; 90% confidence interval = 1.0-4.2). Risk increased with increasing radiation dose until average doses of about 400 rad (4 Gy) were reached and then decreased at higher doses. This pattern is consistent with experimental data for which the down-turn in risk at high doses has been interpreted as due to killing of potentially leukemic cells. The dose-response information was modeled with various RR functions, accounting for the nonhomogeneous distribution of radiation dose during radiotherapy. The local radiation doses to each of 14 bone marrow compartments for each patient were incorporated in the models, and the corresponding risks were summed. A good fit to the observed data was obtained with a linear-exponential function, which included a positive linear induction term and a negative exponential term. The estimate of the excess RR per rad was 0.9%, and the estimated RR at 100 rad (1 Gy) was 1.7. The model proposed in this study of risk proportional to mass exposed and of risk to an individual given by the sum of incremental risks to anatomic sites appears to be applicable to a wide range of dose distributions. Furthermore, the pattern of leukemia incidence associated with different levels of radiation dose is consistent with a model postulating increasing risk with increasing exposure, modified at high doses by increased frequency of cell death, which reduces risk.

Analgesic effect of intramuscular and oral nalbuphine in postoperative pain

In a double-blind study using patients' subjective reports as indices of analgesia, the relative analgesic potency of intramuscular and oral nalbuphine was determined in 104 postoperative patients. Effects of single doses of 3 and 9 mg of intramuscular nalbuphine were compared with those of 15- and 45-mg oral doses of nalbuphine by means of a parallel study design (26 patients per treatment group). When both intensity and duration of analgesia are considered (i.e., total analgesic effect), oral nalbuphine is 1/4 to 1/5 as potent as intramuscular nalbuphine. In terms of peak effect, however, oral nalbuphine is only 1/10 as potent. The oral/parenteral potency ratio for total effect is close to those obtained by Houde et al. in studies of morphine (1/6), metopon (1/5), hydromorphone (1/5), and oxymorphone (1/6) and suggests that oral nalbuphine undergoes substantial biotransformation on first pass through gut mucosa and liver. Since intramuscular nalbuphine is approximately equipotent to morphine, it should be feasible to equal the analgesia induced by the usual intramuscular doses of morphine with reasonable oral doses of nalbuphine. Although nalbuphine is a mixed agonist/antagonist analgesic, no psychotomimetic reactions were observed.

The catecholase activity of Neurospora tyrosinase

A highly purified preparation of tyrosinase from Neurospora crassa was isolated with a view to elucidating its mechanism of action. Both the resting and functioning molecular weights of the enzyme were determined as 33000 plus or minus 2000 and kinetic data in conjunction with binding studies indicated the presence of only one site within the enzyme for binding phenolic substrates. Kinetic constants for several 0-diphenols and for the inhibitors cyanide and benzoic acid were determined and the kinetics are consistent with a mechanism in which either the substrates are bound in a random order or the diphenol binds first. The enzyme forms an oxygenated complex and a complex with hydrogen peroxide and both are detectable spectroscopically