The Role of Institutional Review Boards in Improving the Inclusion of Sex and Gender as Variables in Clinical Research.

ABSTRACT: In orthopaedic clinical research, as in other fields, sex and gender-specific analyses are not consistently performed, despite evidence of sex differences in outcomes. Both institutional review boards (IRBs) and journal editors have a role in impacting the rate at which such analyses are performed and reported. The authority, responsibilities, and potential actions of IRBs are discussed herein, with the aim of setting investigator expectations and propelling changes to the study plan before the research is initiated.

The SHOW RESPECT adaptable framework of considerations for planning how to share trial results with participants, based on qualitative findings from trial participants and site staff.

BACKGROUND: Sharing trial results with participants is a moral imperative, but too often does not happen in appropriate ways. METHODS: We carried out semi-structured interviews with patients (n = 13) and site staff (n = 11), and surveyed 180 patients and 68 site staff who were part of the Show RESPECT study, which tested approaches to sharing results with participants in the context of the ICON8 ovarian cancer trial (ISRCTN10356387). Qualitative and free-text data were analysed thematically, and findings used to develop the SHOW RESPECT adaptable framework of considerations for planning how to share trial results with participants. This paper presents the framework, with illustrations drawn from the Show RESPECT study. RESULTS: Our adaptable 'SHOW RESPECT' framework covers (1) Supporting and preparing trial participants to receive results, (2) HOw will the results reach participants?, (3) Who are the trial participants?, (4) REsults-what do they show?, (5) Special considerations, (6) Provider-who will share results with participants?, (7) Expertise and resources, (8) Communication tools and (9) Timing of sharing results. While the data upon which the framework is based come from a single trial, many of our findings are corroborated by findings from other studies in this area, supporting the transferability of our framework to trials beyond the UK ovarian cancer setting in which our work took place. CONCLUSIONS: This adaptable 'SHOW RESPECT' framework can guide researchers as they plan how to share aggregate trial results with participants. While our data are drawn from a single trial context, the findings from Show RESPECT illustrate how approaches to communication in a specific trial can influence patient and staff experiences of feedback of trial results. The framework generated from these findings can be adapted to fit different trial contexts and used by other researchers to plan the sharing of results with their own participants. TRIAL REGISTRATION: ISRCTN96189403. Registered on February 26, 2019. Show RESPECT was supported by the Medical Research Council (MC_UU_12023/24 and MC_UU_00004/08) and the NIHR CRN.

Acupuncture for hot flashes in hormone receptor-positive breast cancer: A pooled analysis of individual patient data from parallel randomized trials.

BACKGROUND: Hot flashes are a common side effect of endocrine therapy (ET) that contribute to poor quality of life and decreased treatment adherence. METHODS: Patients with breast cancer wo were receiving ET and experiencing hot flashes were enrolled through three parallel, randomized trials conducted in the United States, China, and South Korea. Participants were randomized to either immediate acupuncture (IA) or delayed acupuncture control (DAC). IA participants received 20 acupuncture sessions over 10 weeks, whereas DAC participants received usual care, then crossed over to acupuncture with a reduced intensity. The primary end point was a change in score on the endocrine symptom subscale of the Functional Assessment of Cancer Therapy (FACT)-Endocrine Symptoms between baseline and week 10. Secondary end points included the hot flash score and the FACT-Breast score. A planned pooled analysis of individual patient data was performed using longitudinal mixed models. RESULTS: In total, 158 women with stage 0-III breast cancer were randomized (United States, n = 78; China, n = 40; South Korea, n = 40). At week 10, IA participants reported statistically significant improvements in the endocrine symptom subscale score (mean change ± standard error: 5.1 ± 0.9 vs. 0.2 ± 1.0; p = .0003), the hot flash score (-5.3 ± 0.9 vs. -1.4 ± 0.9; p < .003), and the FACT-Breast total score (8.0 ± 1.6 vs. -0.01 ± 1.6; p = .0005) compared with DAC participants. The effect of the acupuncture intervention differed by site (p = .005). CONCLUSIONS: Acupuncture led to statistically and clinically meaningful improvements in hot flashes, endocrine symptoms, and breast cancer-specific quality of life in women undergoing ET for breast cancer in the United States, China, and South Korea.

An investigation into gender distributions in scholarly publications among dental faculty members in Iran.

BACKGROUND: Research on gender inequality is crucial as it unveils the pervasive disparities that persist across various domains, shedding light on societal imbalances and providing a foundation for informed policy-making. AIM: To investigate gender differences in scientometric indices among faculty members in dental schools across Iran. This included overall data and speciality-specific data. METHODS: The publication profiles of academic staff in all dental schools were examined using the Iranian Scientometric Information Database (ISID, http://isid.research.ac.ir). Variables analyzed were working field, academic degree, the total number of papers, papers per year, total number of citations, percentage of self-citation, h-index, g-index, citations per paper, gender, university type, number of years publishing, proportion of international papers, first-author papers, and corresponding-author papers. Mann-Whitney and Kruskal-Wallis nonparametric tests were used to analyze the relationship between background characteristics and scientometric indicators. The extracted data were analyzed using R v4.0.1. RESULTS: The database included 1850 faculty members, of which about 60% (1104 of 1850) were women. Men (n = 746) had a higher number of papers (6583 vs. 6255) and citations (60410 vs. 39559) compared with women; 234 of the 376 faculty members with no papers were women. Almost half of the women (N = 517 of 1104) were in Type 2 universities, and nearly half of the men (N = 361 of the 746) were faculty members at Type 1 universities (Type 1 universities ranking higher than Type 2 and 3 universities). The medians of scientometric indices were higher in men, except for self-citation percentage (0 (IQR = 2) vs. 0 (IQR = 3), P = 0.083), international papers percentage (0 (IQR = 7.5) vs. 0 (IQR = 16.7), P<0.001). The proportion of corresponding-author papers was more than 62% higher in women (25 (IQR = 50) vs. 15.4 (IQR = 40), P<0.001). Men had a two-fold higher median h-index (2 (IQR = 4) vs. 1 (IQR = 3), P<0.001). Restorative dentistry and pediatric dentistry had the highest men-to-women ratios (1.5 for both). Dental materials and oral and maxillofacial surgery showed the lowest men-to-women ratios (0.42 and 0.5, respectively). CONCLUSIONS: Women made up the majority of dental faculty members in Iran. Nevertheless, men showed better scientometric results in several significant indices. Having identified scientometric information reflecting differences across faculty members, further research is now needed to better understand the drivers of these differences.

Site staff perspectives on communicating trial results to participants: Cost and feasibility results from the Show RESPECT cluster randomised, factorial, mixed-methods trial.

BACKGROUND/AIMS: Sharing trial results with participants is an ethical imperative but often does not happen. Show RESPECT (ISRCTN96189403) tested ways of sharing results with participants in an ovarian cancer trial (ISRCTN10356387). Sharing results via a printed summary improved patient satisfaction. Little is known about staff experience and the costs of communicating results with participants. We report the costs of communication approaches used in Show RESPECT and the views of site staff on these approaches. METHODS: We allocated 43 hospitals (sites) to share results with trial participants through one of eight intervention combinations (2 × 2 × 2 factorial; enhanced versus basic webpage, printed summary versus no printed summary, email list invitation versus no invitation). Questionnaires elicited data from staff involved in sharing results. Open- and closed-ended questions covered resources used to share results and site staff perspectives on the approaches used. Semi-structured interviews were conducted. Interview and free-text data were analysed thematically. The mean additional site costs per participant from each intervention were estimated jointly as main effects by linear regression. RESULTS: We received questionnaires from 68 staff from 41 sites and interviewed 11 site staff. Sites allocated to the printed summary had mean total site costs of sharing results £13.71/patient higher (95% confidence interval (CI): -3.19, 30.60; p = 0.108) than sites allocated no printed summary. Sites allocated to the enhanced webpage had mean total site costs £1.91/patient higher (95% CI: -14, 18.74; p = 0.819) than sites allocated to the basic webpage. Sites allocated to the email list had costs £2.87/patient lower (95% CI: -19.70, 13.95; p = 0.731) than sites allocated to no email list. Most of these costs were staff time for mailing information and handling patients' queries. Most site staff reported no concerns about how they had shared results (88%) and no challenges (76%). Most (83%) found it easy to answer queries from patients about the results and thought the way they were allocated to share results with participants would be an acceptable standard approach (76%), with 79% saying they would follow the same approach for future trials. There were no significant effects of the randomised interventions on these outcomes. Site staff emphasised the importance of preparing patients to receive the results, including giving opt-in/opt-out options, and the need to offer further support, particularly if the results could confuse or distress some patients. CONCLUSIONS: Adding a printed summary to a webpage (which significantly improved participant satisfaction) may increase costs to sites by ~£14/patient, which is modest in relation to the cost of trials. The Show RESPECT communication interventions were feasible to implement. This information could help future trials ensure they have sufficient resources to share results with participants.

Data visualization explorer: A tool for participant representation in pivotal trials of FDA-approved medicinal products.

This paper presents a 2015-2021 US Food and Drug Administration (FDA) Drug Trials Snapshots (DTS) Data Visualization Explorer-an interactive data visualization web-based tool (https://arielcarmeli.shinyapps.io/fda-drug-trial-snapshots-data-explorer) built in R and based on publicly available FDA clinical trial participation data and disease incidence data from the National Cancer Institute and Centers for Disease Control and Prevention. FDA data can be explored by race, ethnicity, sex, age group, therapeutic area, pharmaceutical sponsor, and approval year for clinical trials that supported each of the 339 FDA drug and biologic approvals between 2015 and 2021. This work provides several advantages relative to past literature and DTS reports: a dynamic data visualization tool; race, ethnicity, sex, and age group data presented in one place; data on sponsor; and emphasis on data distributions instead of averages. We present recommendations for improved data access, reporting, and communication to assist leaders in making evidence-based decisions to improve trial representation to enhance health equity.

Data sharing in the context of community-engaged research partnerships.

Over the past 20 years, the National Institutes for Health (NIH) has implemented several policies designed to improve sharing of research data, such as the NIH public access policy for publications, NIH genomic data sharing policy, and National Cancer Institute (NCI) Cancer Moonshot public access and data sharing policy. In January 2023, a new NIH data sharing policy has gone into effect, requiring researchers to submit a Data Management and Sharing Plan in proposals for NIH funding (NIH. Supplemental information to the, 2020b; NIH. Final policy for data, 2020a). These policies are based on the idea that sharing data is a key component of the scientific method, as it enables the creation of larger data repositories that can lead to research questions that may not be possible in individual studies (Alter and Gonzalez, 2018; Jwa and Poldrack, 2022), allows enhanced collaboration, and maximizes the federal investment in research. Important questions that we must consider as data sharing is expanded are to whom do benefits of data sharing accrue and to whom do benefits not accrue? In an era of growing efforts to engage diverse communities in research, we must consider the impact of data sharing for all research participants and the communities that they represent. We examine the issue of data sharing through a community-engaged research lens, informed by a long-standing partnership between community-engaged researchers and a key community health organization (Kruse et al., 2022). We contend that without effective community engagement and rich contextual knowledge, biases resulting from data sharing can remain unchecked. We provide several recommendations that would allow better community engagement related to data sharing to ensure both community and researcher understanding of the issues involved and move toward shared benefits. By identifying good models for evaluating the impact of data sharing on communities that contribute data, and then using those models systematically, we will advance the consideration of the community perspective and increase the likelihood of benefits for all.

Acupuncture for hot flashes in hormone receptor-positive breast cancer, a coordinated multinational study: Rationale and design of the study protocol.

BACKGROUND: Acupuncture has been reported to reduce hot flashes in patients with breast cancer undergoing adjuvant hormonal therapy. Although hot flashes are common, the prevalence varies among cultures, races, and ethnicities; the efficacy of acupuncture across cultures has not been investigated. METHODS: This is a coordinated multinational study, including three parallel randomized trials with a planned analysis of individual patient data, to test the effectiveness of acupuncture on hot flash-related symptoms in hormone receptor-positive breast cancer patients on adjuvant endocrine therapy. Using a standardized acupuncture protocol (total across all three studies of n = 80) versus usual care (total n = 80), symptoms are assessed using changes in the Endocrine Symptom Subscale of Functional Assessment of Cancer Therapy-Endocrine Symptoms. Secondary outcomes include hot flash severity, quality of life, and sleep quality. Differences in response to acupuncture between participants in the three countries will also be explored. DISCUSSION: Here we describe the design of a protocol for a coordinated multinational study, with attention to the complex considerations in developing a multinational research effort testing a non-pharmacologic intervention. This protocol and approach provide guidance for future efforts to evaluate and test non-pharmacologic interventions across multinational populations. TRIAL REGISTRATION: clinicaltrials.gov (Identifier: NCT00797732, registered on December 21, 2018), Chinese Clinical Trial Registry (ChiCTR2100045888), and The Clinical Research Information Service (CRIS) of Korea (Registration number: KCT0003618).

Developing and implementing a self-monitoring toolkit for a coordinated multinational randomized acupuncture trial.

BACKGROUND: In 2019, investigators from China, South Korea and the United States of America initiated a coordinated multinational trial. The trial included three parallel randomized studies with a planned pooled analysis of individual patient data, to test the effectiveness of acupuncture on hot flash-related symptoms in hormone receptor-positive breast cancer patients prescribed adjuvant endocrine therapy. Given the study's approach, there was no central coordinating center or data monitoring committee for the study, so a site performance self-monitoring toolkit was developed and implemented to support study teams in collecting and maintaining high-quality regulatory information, and consistent review of study data and documentation. METHODS: The site performance self-monitoring toolkit was created based on best practices related to post-approval quality assurance/quality improvement (QA/QI) procedures that support data quality. The toolkit included: (1) a binder of essential study management documents and related monitoring logs for sites to complete and maintain (herein called regulator binder), (2) a study start-up checklist, (3) a self-assessment study conduct and oversight checklist to be completed regularly, and (4) a study close-out checklist. In addition, a process of regular virtual meetings to discuss documentation progress coupled with periodic external remote review of completed logs and checklists provided accountability checks. RESULTS: Over the course of the study, the sites in China and South Korea completed the entirety of the site performance self-monitoring toolkit, and successfully submitted their completed materials for review. The process of implementing a self-monitoring toolkit in a multinational integrative medicine study is described qualitatively. Periodic external review of the completed toolkit materials revealed categories of findings. Written follow-up reports were provided to sites and discussion of the documents occurred via separate virtual meetings. CONCLUSIONS: Site study team self-monitoring provides a feasible, consistent, and effective way to review the collection and maintenance of data and regulatory documentation for quality assessment in minimal risk clinical research studies and can augment formal study monitoring activities in higher risk studies. Iterative feedback and support appeared to drive a disciplined approach to maintaining regulatory document compliance and helped sustain investigator and study team engagement in the process. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT03783546 (21/12/2018).

Testing approaches to sharing trial results with participants: The Show RESPECT cluster randomised, factorial, mixed methods trial.

BACKGROUND: Sharing trial results with participants is an ethical imperative but often does not happen. We tested an Enhanced Webpage versus a Basic Webpage, Mailed Printed Summary versus no Mailed Printed Summary, and Email List Invitation versus no Email List Invitation to see which approach resulted in the highest patient satisfaction with how the results were communicated. METHODS AND FINDINGS: We carried out a cluster randomised, 2 by 2 by 2 factorial, nonblinded study within a trial, with semistructured qualitative interviews with some patients (ISRCTN96189403). Each cluster was a UK hospital participating in the ICON8 ovarian cancer trial. Interventions were shared with 384 ICON8 participants who were alive and considered well enough to be contacted, at 43 hospitals. Hospitals were allocated to share results with participants through one of the 8 intervention combinations based on random permutation within blocks of 8, stratified by number of participants. All interventions contained a written plain English summary of the results. The Enhanced Webpage also contained a short video. Both the Enhanced Webpage and Email contained links to further information and support. The Mailed Printed Summary was opt-out. Follow-up questionnaires were sent 1 month after patients had been offered the interventions. Patients' reported satisfaction was measured using a 5-point scale, analysed by ordinal logistic regression estimating main effects for all 3 interventions, with random effects for site, restricted to those who reported receiving the results and assuming no interaction. Data collection took place in 2018 to 2019. Questionnaires were sent to 275/384 randomly selected participants and returned by 180: 90/142 allocated Basic Webpage, 90/133 Enhanced Webpage; 91/141 no Mailed Printed Summary, 89/134 Mailed Printed Summary; 82/129 no Email List Invitation, 98/146 Email List Invitation. Only 3 patients opted out of receiving the Mailed Printed Summary; no patients signed up to the email list. Patients' satisfaction was greater at sites allocated the Mailed Printed Summary, where 65/81 (80%) were quite or very satisfied compared to sites with no Mailed Printed Summary 39/64 (61%), ordinal odds ratio (OR) = 3.15 (1.66 to 5.98, p < 0.001). We found no effect on patient satisfaction from the Enhanced Webpage, OR = 1.47 (0.78 to 2.76, p = 0.235) or Email List Invitation, OR = 1.38 (0.72 to 2.63, p = 0.327). Interviewees described the results as interesting, important, and disappointing (the ICON8 trial found no benefit). Finding out the results made some feel their trial participation had been more worthwhile. Regardless of allocated group, patients who received results generally reported that the information was easy to understand and find, were glad and did not regret finding out the results. The main limitation of our study is the 65% response rate. CONCLUSIONS: Nearly all respondents wanted to know the results and were glad to receive them. Adding an opt-out Mailed Printed Summary alongside a webpage yielded the highest reported satisfaction. This study provides evidence on how to share results with other similar trial populations. Further research is needed to look at different results scenarios and patient populations. TRIAL REGISTRATION: ISRCTN: ISRCTN96189403.

Evaluating the frequency of English language requirements in clinical trial eligibility criteria: A systematic analysis using ClinicalTrials.gov.

BACKGROUND: A number of prior studies have demonstrated that research participants with limited English proficiency in the United States are routinely excluded from clinical trial participation. Systematic exclusion through study eligibility criteria that require trial participants to be able to speak, read, and/or understand English affects access to clinical trials and scientific generalizability. We sought to establish the frequency with which English language proficiency is required and, conversely, when non-English languages are affirmatively accommodated in US interventional clinical trials for adult populations. METHODS AND FINDINGS: We used the advanced search function on ClinicalTrials.gov specifying interventional studies for adults with at least 1 site in the US. In addition, we used these search criteria to find studies with an available posted protocol. A computer program was written to search for evidence of English or Spanish language requirements, or the posted protocol, when available, was manually read for these language requirements. Of the 14,367 clinical trials registered on ClinicalTrials.gov between 1 January 2019 and 1 December 2020 that met baseline search criteria, 18.98% (95% CI 18.34%-19.62%; n = 2,727) required the ability to read, speak, and/or understand English, and 2.71% (95% CI 2.45%-2.98%; n = 390) specifically mentioned accommodation of translation to another language. The remaining trials in this analysis and the following sub-analyses did not mention English language requirements or accommodation of languages other than English. Of 2,585 federally funded clinical trials, 28.86% (95% CI 27.11%-30.61%; n = 746) required English language proficiency and 4.68% (95% CI 3.87%-5.50%; n = 121) specified accommodation of other languages; of the 5,286 industry-funded trials, 5.30% (95% CI 4.69%-5.90%; n = 280) required English and 0.49% (95% CI 0.30%-0.69%; n = 26) accommodated other languages. Trials related to infectious disease were less likely to specify an English requirement than all registered trials (10.07% versus 18.98%; relative risk [RR] = 0.53; 95% CI 0.44-0.64; p < 0.001). Trials related to COVID-19 were also less likely to specify an English requirement than all registered trials (8.18% versus 18.98%; RR = 0.43; 95% CI 0.33-0.56; p < 0.001). Trials with a posted protocol (n = 366) were more likely than all registered clinical trials to specify an English requirement (36.89% versus 18.98%; RR = 1.94, 95% CI 1.69-2.23; p < 0.001). A separate analysis of studies with posted protocols in 4 therapeutic areas (depression, diabetes, breast cancer, and prostate cancer) demonstrated that clinical trials related to depression were the most likely to require English (52.24%; 95% CI 40.28%-64.20%). One limitation of this study is that the computer program only searched for the terms "English" and "Spanish" and may have missed evidence of other language accommodations. Another limitation is that we did not differentiate between requirements to read English, speak English, understand English, and be a native English speaker; we grouped these requirements together in the category of English language requirements. CONCLUSIONS: A meaningful percentage of US interventional clinical trials for adults exclude individuals who cannot read, speak, and/or understand English, or are not native English speakers. To advance more inclusive and generalizable research, funders, sponsors, institutions, investigators, institutional review boards, and others should prioritize translating study materials and eliminate language requirements unless justified either scientifically or ethically.

Returning aggregate results of clinical trials: Empirical data of patient preferences.

INTRODUCTION: The purpose of this research was to understand the preferences of patients receiving integrative medicine services for return of aggregate study results. METHODS: A brief online survey (survey 1) was sent to 341 cancer patients receiving integrative medicine interventions; subsequently, a minimally revised survey (survey 2) was sent to 812 individuals with various medical conditions who had been either research participants in integrative medicine studies (n = 446) or patients (n = 346) of mind-body medicine. RESULTS: Feedback to a model plain language summary was elicited from survey 1 and survey 2 respondents. Seventy-seven survey recipients (23%) responded to survey 1, and 134 survey recipients (17%) responded to survey 2. The majority of respondents to the surveys were female and 51-70 years of age. Ninety percent of responders to survey 1 and 89% of responders to survey 2 indicated that researchers should share overall results of a study with participants. In terms of the means of result distribution, 37%-47% preferred email, while 22%-27% indicated that, as long as the results are shared, it did not matter how this occurred. Of 38 survey 1 respondents who had previously participated in a clinical trial, 37% had received the results of their study. In survey 2, 63 individuals indicated that they previously participated in clinical trials, but only 16% recalled receiving results. CONCLUSIONS: These results confirm that the majority (89%-90%) of integrative medicine patients are interested in receiving the results of clinical trials. The majority (82%-94%) of respondents felt the model plain language summary of results provided was helpful.

Enhancing safety reporting in adult ambulatory oncology with a clinician champion: a practice innovation.

This article examines whether a patient safety "champion" on an ambulatory chemotherapy infusion unit can increase reporting of adverse events and close calls. Reporting rates increased substantially on both intervention and control units. It was accompanied by more reports of medical errors and conditions that worried staff and fewer reports of service quality incidents. The facilitated reporting method described here is a novel approach to incident reporting, complements the spontaneous reporting systems used in hospitals and some ambulatory care settings, and may help to build a safety culture. By identifying errors and worrisome conditions, it may help managers identify problems before they lead to harm.

Patient-reported safety and quality of care in outpatient oncology.

BACKGROUND: Although patients suffer the effects of medical errors and iatrogenic injuries, little is known about their ability to recognize these events in ambulatory specialty care. METHODS: At a Boston cancer center in 2004, 193 adult oncology patients treated on a chemotherapy infusion unit were interviewed by four patient safety liaisons--volunteers recruited from the organization's Adult Patient and Family Advisory Council. RESULTS: Among 193 patients, 83 reported 121 incidents. Investigators classified 2 (1%) adverse events, 4 (2%) close calls, 14 (7%) errors without risk of harm, and 101 (52%) service quality incidents. Respondents reported high staff compliance with safe practices such as identity checking (95%). Examining the most serious described by each of 42 (22%) respondents who reported a recent unsafe experience, investigators classified only one adverse event, 3 close calls, 9 harmless errors, and 27 service quality incidents. DISCUSSION: Patients' perception of unsafe care was surprising, given the same patients' recognition of consistent application of safe practices, such as the use of two forms of identification before performing tests and administering treatments. Many ambulatory oncology patients also reported poor service quality. The relationship between patient perception of safe care, medical injury, and service quality merits further study.

Gelsolin overexpression alters actin dynamics and tyrosine phosphorylation of lipid raft-associated proteins in Jurkat T cells.

Upon T cell receptor engagement, both the actin cytoskeleton and substrates of tyrosine phosphorylation are remodeled to create a signaling complex at the interface of the antigen-presenting cell and responding T cell. While T cell signaling has been shown to regulate actin reorganization, the mechanisms by which changes in actin dynamics affect early T cell signaling have not been fully explored. Using gelsolin, an actin-binding protein with capping and severing activities, and latrunculin, an actin-depolymerizing agent, we have further investigated the interplay between actin dynamics and the regulation of T cell signaling. Overexpression of gelsolin altered actin dynamics in Jurkat T cells, and alteration of actin dynamics correlated with dysregulation of tyrosine phosphorylation of raft-associated substrates. This perturbation of tyrosine phosphorylation was correlated with inhibition of activation-dependent signaling pathways regulating Erk-1/2 phosphorylation, NF-AT transcriptional activation and IL-2 production. Modification of actin by the depolymerizing agent latrunculin also altered the tyrosine phosphorylation patterns of proteins associated with lipid rafts, and pre-treatment with latrunculin inhibited anti-CD3 mAb-mediated NF-AT activation. Thus, our data indicate that actin cytoskeletal dynamics modulate the tyrosine phosphorylation of raft-associated proteins and subsequent downstream signal transduction.

Ex vivo rapamycin generates donor Th2 cells that potently inhibit graft-versus-host disease and graft-versus-tumor effects via an IL-4-dependent mechanism.

Rapamycin (sirolimus) inhibits graft-vs-host disease (GVHD) and polarizes T cells toward Th2 cytokine secretion after allogeneic bone marrow transplantation (BMT). Therefore, we reasoned that ex vivo rapamycin might enhance the generation of donor Th2 cells capable of preventing GVHD after fully MHC-disparate murine BMT. Using anti-CD3 and anti-CD28 costimulation, CD4+ Th2 cell expansion was preserved partially in high-dose rapamycin (10 microM; Th2.rapa cells). Th2.rapa cells secreted IL-4 yet had reduced IL-5, IL-10, and IL-13 secretion relative to control Th2 cells. BMT cohorts receiving wild-type (WT) Th2.rapa cells, but not Th2.rapa cells generated from IL-4-deficient (knockout) donors, had marked Th2 skewing post-BMT and greatly reduced donor anti-host T cell alloreactivity. Histologic studies demonstrated that Th2.rapa cell recipients had near complete abrogation of skin, liver, and gut GVHD. Overall survival in recipients of WT Th2.rapa cells, but not IL-4 knockout Th2.rapa cells, was constrained due to marked attenuation of an allogeneic graft-vs-tumor (GVT) effect against host-type breast cancer cells. Delay in Th2.rapa cell administration until day 4, 7, or 14 post-BMT enhanced GVT effects, moderated GVHD, and improved overall survival. Therefore, ex vivo rapamycin generates enhanced donor Th2 cells for attempts to balance GVHD and GVT effects.

CD28 engagement promotes actin polymerization through the activation of the small Rho GTPase Cdc42 in human T cells.

Engagement of the costimulatory molecule CD28 is an important step in the optimal activation of T cells. Nevertheless, the specific role of CD28 in the formation of the immunological synapse and cytoskeletal changes that occur upon TCR/CD3 complex engagement is still poorly understood. Using Ab-coated surfaces, we show that CD28 engagement in the absence of any other signal induced the formation of cytoplasmic elongations enriched in filamentous actin (F-actin), in this work called filopodia or microspikes. Such structures were specific for engagement of CD28 on mAb-coated surfaces because they could not be observed in surfaces coated with either poly(L-lysine) or anti-CD3 mAb. The signaling pathway coupling CD28 to cytoskeletal rearrangements required Src-related kinase activity and promoted Vav phosphorylation and Cdc42 activation independently of the zeta-chain-associated kinase (ZAP-70). CD28-induced filopodia required Cdc42 GTPase activity, but not the related Rho GTPase Rac1. Moreover, Cdc42 colocalized to areas of increased F-actin. Our results support a specific role for the activation of the small Rho GTPase Cdc42 in the actin reorganization mediated by CD28 in human T cells.

Inhibition of actin polymerization enhances commitment to and execution of apoptosis induced by withdrawal of trophic support.

We have previously shown, using jasplakinolide, that stabilization of the actin cytoskeleton enhanced apoptosis induced upon cytokine withdrawal (Posey and Bierer [1999] J. Biol. Chem. 274:4259-4265). It remained possible, however, that a disruption in the regulation of actin dynamics, and not simply F-actin stabilization, was required to affect the transduction of an apoptotic signal. We have now tested the effects of cytochalasin D, a well-characterized agent that promoted actin depolymerization. Actin depolymerization did not affect CD95 (Fas)-induced death of Jurkat T cells in the time course studied but did enhance the commitment to cytokine withdrawal-induced apoptosis of factor-dependent cell lines. The induction of cell death was not the result of direct cytoskeletal collapse, since treatment of the cells with cytochalasin D in the presence of IL-2 did not promote death. As with jasplakinolide, the enhancement of commitment to apoptosis could be delayed by overexpression of the anti-apoptotic protein Bcl-x(L), but, unlike jasplakinolide, cytochalasin D modestly affected the "execution" stage of apoptosis as well. Taken together, these results suggest that changes in actin dynamics, i.e., the rate of actin polymerization and depolymerization, modulate the transduction of the apoptotic signal committing lymphocytes, withdrawn from required growth factors, to the death pathway.

Differences between CEM and human peripheral blood T lymphocytes in cAMP-dependent HIV viral fusion and CXCR4 expression.

CXCR4, a G-protein-coupled chemokine receptor and HIV coreceptor, has been shown to play a central role in both chemotaxis and HIV-1-entry into T lymphocytes. Recent efforts have focused on identifying the signaling pathways that modulate CXCR4 expression in order to modulate HIV infectivity. Toward this effort, we previously demonstrated cAMP-dependent up-regulation of CXCR4 mRNA and protein in human peripheral blood T cells (PBL), resulting in increased HIV infectivity. Regulation of CXCR4 mRNA was mediated, in part, by a CRE element within the CXCR4 promoter. In order to develop a model system to examine cAMP regulation, the responses of the T lymphoblastoid cell line CEM were compared to those of human PBL. In sharp contrast to that of human PBL, HIV-1 entry into CEM cells was dramatically reduced in response to dibutyryl cAMP (DcAMP). Furthermore, while total cellular and cell surface CXCR4 protein levels were up-regulated in human PBL and in Jurkat T cells in response to DcAMP or forskolin stimulation, CXCR4 levels were unchanged by stimulation in CEM cells. Surprisingly, the CXCR4 promoter (nucleotides -1098 to +59) fused to luciferase was found to be activated similarly in CEM and Jurkat cells in response to DcAMP in a concentration-dependent manner. RT-PCR analyses confirmed that CXCR4 mRNA levels were increased by cAMP agonists. Taken together, our findings suggest that total and cell surface CXCR4 protein expression is regulated differently in human PBL than in CEM cells, a finding that correlates with the differential HIV-1 fusion in response to cAMP signaling. Moreover, our results suggest that, for CXCR4 expression and HIV viral infectivity, CEM cells may not be a faithful model of primary human lymphocytes.