Patient-reported anticipated barriers and benefits to sharing cancer genetic risk information with family members.

While prior studies have largely focused on family communication of diagnostic single-gene test results or specific types of cancer testing results, far less work has investigated family communication of cancer-related genetic results that include multi-gene panels, a broad array of cancer types/stages, and participants without family history of cancer. The study we report here examined individuals' anticipated barriers and benefits to sharing genetic information with family members. An 80+ gene panel was performed on participants recruited from Mayo Clinic, diagnosed with different cancer types, who did not have a family history suggestive of an inherited risk. Participants completed a 49-item survey before receiving genetic test results. Family variant testing was provided to family members at no cost, allowing factors influencing intent to share to be examined in the absence of financial burdens. In all, 1721 of 2984 individuals who received genetic testing completed the survey (57.7% completion rate). Participants' intent to share with parents, siblings, and children was inversely related to the number of anticipated barriers to sharing and directly related to the number of anticipated benefits to sharing. Of those participants who did not intend to share with parents, siblings, and adult children, 64.8%, 30.3%, and 67.6% reported that there were no barriers, while 17.1%, 24.5%, and 40.2.% reported there were no benefits. Findings indicate that barriers to sharing genetic information with family members vary across family member types, and an inability to identify at least one benefit of sharing with family members is a predictor of intent not to share.

Lay understandings of drug-gene interactions: The right medication, the right dose, at the right time, but what are the right words?

As pharmacogenomic (PGx) testing increases in popularity, lay concepts of drug-gene interactions set the stage for shared decision making in precision medicine. Few studies explore what recipients of PGx results think is happening in their bodies when a drug-gene interaction is discovered. To characterize biobank participants' understanding of PGx research results, we conducted a focus group study, which took place after PGx variants conferring increased risk of dihydropyrimidine dehydrogenase (DPD) deficiency were disclosed to biobank contributors. DPD deficiency confers an increased risk of adverse reaction to commonly used cancer chemotherapeutics. Ten focus groups were conducted, ranging from two to eight participants. Fifty-four individuals participated in focus groups. A framework approach was used for descriptive and explanatory analysis. Descriptive themes included participants' efforts to make sense of PGx findings as they related to: (1) health implications, (2) drugs, and (3) genetics. Explanatory analysis supplied a functional framework of how participant word choices can perform different purposes in PGx communication. Results bear three main implications for PGx research-related disclosure. First, participants' use of various terms suggest participants generally understanding their PGx results, including how positive PGx results differ from positive disease susceptibility genetic results. Second, PGx disclosure in biobanking can involve participant conflation of drug-gene interactions with allergies or other types of medical reactions. Third, the functional framework suggests a need to move beyond a deficit model of genetic literacy in PGx communication. Together, findings provide an initial evidence base for supporting bidirectional expert-recipient PGx results communication.

Factors that Influence Intent to Share Genetic Information Related to Cancer Risk with Family Members.

We describe factors influencing patient decisions to share positive cancer genetic test results with family members. We focused on patients who were diagnosed with several different cancer types but did not have a family history that was suggestive of an inherited risk. Participants were recruited from Mayo Clinic and had been recently diagnosed with cancer. An 80+ gene panel was performed. Before receiving genetic test results, patients completed a 49-item survey on their intent to share their results with relatives. 1,721 (57.7%) of 2,984 individuals who elected to pursue genetic testing completed the survey. Most patients planned to share cancer-related genetic results with a spouse or partner (97.0%), at least one adult child (92.2%), at least one sibling (86.2%), and with at least one parent (70.3%). Familial support scores and familial communication scores were predictive of intent to share cancer-related genetic test results. Our data highlight differences in family communication capacity and support that are important for clinicians to consider when supporting patients who wish to share cancer-related genetic test results with family members. Our data point to several potential interventional strategies that might increase the likelihood of cancer-related genetic test results being shared with family members at risk.

Returning negative results from large-scale genomic screening: Experiences from the eMERGE III network.

Population-based genomic screening has the potential to improve health outcomes by identifying genetic causes of disease before they occur. While much attention has been paid to supporting the needs of the small percentage of patients who will receive a life-altering positive genomic screening result that requires medical attention, little attention has been given to the communication of negative screening results. As there are currently no best practices for returning negative genomic screening results, we drew on experiences across the electronic medical records and genomics (eMERGE) III Network to highlight the diversity of reporting methods employed, challenges encountered in reporting negative test results, and "lessons learned" across institutions. A 60-item survey that consisted of both multiple choice and open-ended questions was created to gather data across institutions. Even though institutions independently developed procedures for reporting negative results, and had very different study populations, we identified several similarities of approach, including but not limited to: returning results by mail, placing results in the electronic health record via an automated process, reporting results to participants' primary care provider, and providing genetic counseling to interested patients at no cost. Differences in procedures for reporting negative results included: differences in terminology used to describe negative results, definitions of negative results, guidance regarding the meaning of negative results for participants and their family members, and recommendations for clinical follow up. Our findings highlight emerging practices for reporting negative genomic screening results and highlight the need to create patient education and clinical support tools for reporting negative screening results.

Loss of Bcl-6-Expressing T Follicular Helper Cells and Germinal Centers in COVID-19.

Humoral responses in coronavirus disease 2019 (COVID-19) are often of limited durability, as seen with other human coronavirus epidemics. To address the underlying etiology, we examined post mortem thoracic lymph nodes and spleens in acute SARS-CoV-2 infection and observed the absence of germinal centers and a striking reduction in Bcl-6+ germinal center B cells but preservation of AID+ B cells. Absence of germinal centers correlated with an early specific block in Bcl-6+ TFH cell differentiation together with an increase in T-bet+ TH1 cells and aberrant extra-follicular TNF-α accumulation. Parallel peripheral blood studies revealed loss of transitional and follicular B cells in severe disease and accumulation of SARS-CoV-2-specific "disease-related" B cell populations. These data identify defective Bcl-6+ TFH cell generation and dysregulated humoral immune induction early in COVID-19 disease, providing a mechanistic explanation for the limited durability of antibody responses in coronavirus infections, and suggest that achieving herd immunity through natural infection may be difficult.

The Loss of Bcl-6 Expressing T Follicular Helper Cells and the Absence of Germinal Centers in COVID-19.

Humoral responses in COVID-19 disease are often of limited durability, as seen with other human coronavirus epidemics. To address the underlying etiology, we examined postmortem thoracic lymph nodes and spleens in acute SARS-CoV-2 infection and observed the absence of germinal centers, a striking reduction in Bcl-6+ germinal center B cells but preservation of AID+ B cells. Absence of germinal centers correlated with an early specific block in Bcl-6+TFH cell differentiation together with an increase in T-bet+TH1 cells and aberrant extra-follicular TNF-a accumulation.  Parallel peripheral blood studies revealed loss of transitional and follicular B cells in severe disease and accumulation of SARS-CoV-2-specific "disease-related" B cell populations. These data identify defective Bcl-6+TFH cell generation and dysregulated humoral immune induction early in COVID-19 disease, providing a mechanistic explanation for the limited durability of antibody responses in coronavirus infections and suggest that achieving herd immunity through natural infection may be difficult. Funding: This work was supported by NIH U19 AI110495 to SP, NIH R01 AI146779 to AGS, NIH R01AI137057 and DP2DA042422 to DL, BMH was supported by NIGMS T32 GM007753, TMC was supported by T32 AI007245. Funding for these studies from the Massachusetts Consortium of Pathogen Readiness, the Mark and Lisa Schwartz Foundation and Enid Schwartz is also acknowledged. Conflict of Interest: None. Ethical Approval: This study was performed with the approval of the Institutional Review Boards at the Massachusetts General Hospital and the Brigham and Women's Hospital.

Differential Roles of IL-2 Signaling in Developing versus Mature Tregs.

Although Foxp3+ regulatory T cells (Tregs) require interleukin-2 (IL-2) for their development, it has been unclear whether continuing IL-2 signals are needed to maintain lineage stability, survival, and suppressor function in mature Tregs. We generated mice in which CD25, the main ligand-binding subunit of the IL-2 receptor, can be inducibly deleted from Tregs after thymic development. In contrast to Treg development, we find that IL-2 is dispensable for maintaining lineage stability in mature Tregs. Although continuous IL-2 signaling is needed for long-term Treg survival, CD25-deleted Tregs may persist for several weeks in vivo using IL-7. We also observe defects in glycolytic metabolism and suppressor function following CD25 deletion. Thus, unlike developing Tregs in which the primary role of IL-2 is to initiate Foxp3 expression, mature Tregs require continuous IL-2 signaling to maintain survival and suppressor function, but not to maintain lineage stability.

Cutting Edge: TGF-ß and Phosphatidylinositol 3-Kinase Signals Modulate Distinct Metabolism of Regulatory T Cell Subsets.

Murine Foxp3+ regulatory T cells (Tregs) differentiated in vitro (induced Tregs [iTregs]) in the presence of anti-inflammatory cytokine TGF-ß rely predominantly upon lipid oxidation to fuel mitochondrial oxidative phosphorylation. Foxp3 expression underlies this metabolic preference, as it suppresses glycolysis and drives oxidative phosphorylation. In this study, we show that in contrast to iTregs, thymic-derived Tregs (tTregs), engage in glycolysis and glutaminolysis at levels comparable to effector T cells despite maintained Foxp3 expression. Interestingly, exposure of tTregs to the anti-inflammatory cytokine TGF-ß represses PI3K-mediated mTOR signaling, inhibits glucose transporter and Hk2 expression, and reprograms their metabolism to favor oxidative phosphorylation. Conversely, replicating the effects of inflammation via elevation of PI3K signaling has minimal effects on tTregs but dramatically enhances the glycolysis of normally oxidative iTregs, resulting in reduction of Foxp3 expression. Collectively, these findings suggest both extrinsic and intrinsic factors govern the unique metabolic signature of Treg subsets.

B Cells Drive Autoimmunity in Mice with CD28-Deficient Regulatory T Cells.

Follicular regulatory T (TFR) cells are a newly defined regulatory T cell (Treg) subset that suppresses follicular helper T cell-mediated B cell responses in the germinal center reaction. The precise costimulatory signal requirements for proper TFR cell differentiation and function are still not known. Using conditional knockout strategies of CD28, we previously demonstrated that loss of CD28 signaling in Tregs caused autoimmunity in mice (termed CD28-ΔTreg mice), characterized by lymphadenopathy, accumulation of activated T cells, and cell-mediated inflammation of the skin and lung. In this study, we show that CD28 signaling is required for TFR cell differentiation. Treg-specific deletion of CD28 caused a reduction in TFR cell numbers and function, which resulted in increased germinal center B cells and Ab production. Moreover, residual CD28-deficient TFR cells showed a diminished suppressive capacity as assessed by their ability to inhibit Ab responses in vitro. Surprisingly, genetic deletion of B cells in CD28-ΔTreg mice prevented the development of lymphadenopathy and CD4+ T cell activation, and autoimmunity that mainly targeted skin and lung tissues. Thus, autoimmunity occurring in mice with CD28-deficient Tregs appears to be driven primarily by loss of TFR cell differentiation and function with resulting B cell-driven inflammation.

Kinetically-defined component actions in gene repression.

Gene repression by transcription factors, and glucocorticoid receptors (GR) in particular, is a critical, but poorly understood, physiological response. Among the many unresolved questions is the difference between GR regulated induction and repression, and whether transcription cofactor action is the same in both. Because activity classifications based on changes in gene product level are mechanistically uninformative, we present a theory for gene repression in which the mechanisms of factor action are defined kinetically and are consistent for both gene repression and induction. The theory is generally applicable and amenable to predictions if the dose-response curve for gene repression is non-cooperative with a unit Hill coefficient, which is observed for GR-regulated repression of AP1LUC reporter induction by phorbol myristate acetate. The theory predicts the mechanism of GR and cofactors, and where they act with respect to each other, based on how each cofactor alters the plots of various kinetic parameters vs. cofactor. We show that the kinetically-defined mechanism of action of each of four factors (reporter gene, p160 coactivator TIF2, and two pharmaceuticals [NU6027 and phenanthroline]) is the same in GR-regulated repression and induction. What differs is the position of GR action. This insight should simplify clinical efforts to differentially modulate factor actions in gene induction vs. gene repression.