The oral microbiome in alcohol use disorder: a longitudinal analysis during inpatient treatment

Background

Alcohol use disorder (AUD)-induced disruption of oral microbiota can lead to poor oral health; there have been no studies published examining the longitudinal effects of alcohol use cessation on the oral microbiome.

Aim

To investigate the oral microbiome during alcohol cessation during inpatient treatment for AUD.

Methods

Up to 10 oral tongue brushings were collected from 22 AUD patients during inpatient treatment at the National Institutes of Health. Alcohol use history, smoking, and periodontal disease status were measured. Oral microbiome samples were sequenced using 16S rRNA gene sequencing.

Results

Alpha diversity decreased linearly during treatment across the entire cohort (P = 0.002). Alcohol preference was associated with changes in both alpha and beta diversity measures. Characteristic tongue dorsum genera from the Human Microbiome Project such as Streptococcus, Prevotella, Veillonella and Haemophilus were highly correlated in AUD. Oral health-associated genera that changed longitudinally during abstinence included Actinomyces, Capnocytophaga, Fusobacterium, Neisseria and Prevotella.

Conclusion

The oral microbiome in AUD is affected by alcohol preference. Patients with AUD often have poor oral health but abstinence and attention to oral care improve dysbiosis, decreasing microbiome diversity and periodontal disease-associated genera while improving acute oral health.

FAAH and CNR1 Polymorphisms in the Endocannabinoid System and Alcohol-Related Sleep Quality

Sleep disturbances are common among individuals with alcohol use disorder (AUD) and may not resolve completely with short-term abstinence from alcohol, potentially contributing to relapse to drinking. The endocannabinoid system (ECS) is associated with both sleep and alcohol consumption, and genetic variation in the ECS may underlie sleep-related phenotypes among individuals with AUD. In this study, we explored the influence of genetic variants in the ECS (Cannabinoid receptor 1/CNR1: rs806368, rs1049353, rs6454674, rs2180619, and Fatty Acid Amide Hydrolase/FAAH rs324420) on sleep quality in individuals with AUD (N = 497) and controls without AUD (N = 389). We assessed subjective sleep quality (from the Pittsburgh Sleep Quality Index/PSQI) for both groups at baseline and objective sleep efficiency and duration (using actigraphy) in a subset of individuals with AUD at baseline and after 4 weeks of inpatient treatment. We observed a dose-dependent relationship between alcohol consumption and sleep quality in both AUD and control groups. Sleep disturbance, a subscale measure in PSQI, differed significantly among CNR1 rs6454674 genotypes in both AUD (p = 0.015) and controls (p = 0.016). Only among controls, neuroticism personality scores mediated the relationship between genotype and sleep disturbance. Objective sleep measures (sleep efficiency, wake bouts and wake after sleep onset), differed significantly by CNR1 rs806368 genotype, both at baseline (p = 0.023, 0.029, 0.015, respectively) and at follow-up (p = 0.004, p = 0.006, p = 0.007, respectively), and by FAAH genotype for actigraphy recorded sleep duration at follow-up (p = 0.018). These relationships suggest a significant role of the ECS in alcohol-related sleep phenotypes.

Longitudinal gut microbiome changes in alcohol use disorder are influenced by abstinence and drinking quantity

Many patients with alcohol use disorder (AUD) consume alcohol chronically and in large amounts that alter intestinal microbiota, damage the gastrointestinal tract, and thereby injure other organs via malabsorption and intestinal inflammation. We hypothesized that alcohol consumption and subsequent abstinence would change the gut microbiome in adults admitted to a treatment program. Stool and oral specimens, diet data, gastrointestinal assessment scores, anxiety, depression measures and drinking amounts were collected longitudinally for up to 4 weeks in 22 newly abstinent inpatients with AUD who were dichotomized as less heavy drinkers (LHD, <10 drinks/d) and very heavy drinkers (VHD, 10 or more drinks/d). Next-generation 16 S rRNA gene sequencing was performed to measure the gut and oral microbiome at up to ten time points/subject and LHD and VHD were compared for change in principal components, Shannon diversity index and specific genera. The first three principal components explained 46.7% of the variance in gut microbiome diversity across time and all study subjects, indicating the change in gut microbiome following abstinence. The first time point was an outlier in three-dimensional principal component space versus all other time points. The gut microbiota in LHD and VHD were significantly dissimilar in change from day 1 to day 5 (p = .03) and from day 1 to week 3 (p = .02). The VHD drinking group displayed greater change from baseline. The Shannon diversity index of the gut microbiome changed significantly during abstinence in five participants. In both groups, the Shannon diversity was lower in the oral microbiome than gut. Ten total genera were shared between oral and stool in the AUD participants. These data were compared with healthy controls from the Human Microbiome Project to investigate the concept of a core microbiome. Rapid changes in gut microbiome following abstinence from alcohol suggest resilience of the gut microbiome in AUD and reflects the benefits of refraining from the highest levels of alcohol and potential benefits of abstinence.

Sleep Regularity Index in Patients with Alcohol Dependence: Daytime Napping and Mood Disorders as Correlates of Interest

Alcohol use disorder (AUD) is often accompanied by comorbid conditions, including sleep disturbances related to sleep regularity and timing. The Sleep Regularity Index (SRI) is a novel measure that assesses the probability that an individual is awake (vs. asleep) at any two time points 24 h apart. We calculated actigraphy-based SRI on 124 participants with alcohol dependence to capture the effects of changes in sleep timing and duration among patients enrolled in an inpatient alcohol treatment program. During the course of the study, the mean SRI increased between weeks 1 and 3 (75.4 to 77.8), thus indicating slightly improved sleep quality and regularity during alcohol treatment. Individuals within the bottom quartile of SRI scores at week 1 improved significantly over time. Average total SRI for individuals with no mood disorders was slightly higher than that for individuals with one or more mood disorders. Increased SRI scores were associated with lower total nap duration from week 1 to week 3. Increased SRI scores were associated with decreased mental/physical exhaustion scores from week 1 to week 3. The SRI could be a target for assessment/intervention in certain sub-groups of individuals undergoing inpatient treatment for AUD.

2577. Periodontal Disease and the Oral Microbiome in Alcohol-Dependent Individuals

Background

Periodontal disease results from a polymicrobial infection composed of pathogenic bacteria that colonize the oral cavity, resulting in loss of periodontal attachment and alveolar bone. Periodontitis can increase the risk or exacerbate other comorbidities. Alcohol use increases the risk of periodontitis, but there is little knowledge about periodontitis among people who misuse alcohol.

Methods

As part of a larger oral and gut microbiome study, this analysis examines the oral microbiome in the occurrence and severity of periodontitis among alcohol-dependent (AD) subjects undergoing a 28-day inpatient alcohol treatment program. Tongue brushings were collected from 22 subjects within the first week of admission, and 16S rDNA sequencing was performed. All subjects had a dental examination during the inpatient stay. This analysis divided periodontal disease status into three major groups–no disease, mild or moderate disease, and severe disease. One-way ANOVA was used to compare microbial genera across the 3 groups.

Results

Nineteen (86%) of the subjects had periodontitis: 16 had mild or moderate disease, and 3 had severe disease. Statistically different microbial genera in at least one of the three groups (P ≤ 0.05 corresponding to FDR ≤ 0.25) that had a relative abundance of at least 0.5% include: Bifidobacterium, Lactobacillus, Parvimonas, Peptostreptococcus, Porphyromonas, and Treponema. Surprisingly, the subjects with no periodontitis had increased abundances of genera that are often pathogens, Porphyromonas and Peptostreptococcus. Subjects with severe periodontitis had increased abundances of known pathogens Treponema and Parvimonas, as well as Lactobacillus, which has been associated with dental caries.

Conclusion

We observed that periodontitis accompanies chronic AD, given that 86% of our subjects had the disease. While some microbiome differences for individuals with and without periodontitis were not consistent with the existing literature, this may have many explanations. Future studies should consider how chronic AD could change the microbial ecology of the mouth and lead to further infection as well as utilizing multiple oral sites and a larger sample size to better understand the relationship between AD and periodontal disease.

Intramural funds from NIH

Disclosures

All authors: No reported disclosures.

Identification of Distinct Latent Classes Related to Sleep, PTSD, Depression, and Anxiety in Individuals Diagnosed With Severe Alcohol Use Disorder

Objective/Background: Alcohol use disorders (AUDs) are often accompanied by comorbid physiologic and psychosocial conditions, including sleep disturbances. Sleep disturbances in these individuals may be associated with increased risk of relapse to drinking following detoxification and rehabilitation. Participants: The sample of inpatient treatment-seeking individuals with AUDs (N = 164) was 70.1% male and 47.6% African American with a mean age of 45.6 years (±9.5 years). Methods: Latent class analysis (LCA) was used to identify unmeasured class membership based on seven indicators: maximum Clinical Institute Withdrawal Assessment (CIWA) scores; sleep efficiency (actigraphy); sleep disturbances (Pittsburgh Sleep Quality Index-PSQI); anxiety or depression (Comprehensive Psychopathological Rating Scale [CPRS]); and current and lifetime posttraumatic stress disorder (PTSD). Results: The average number of drinking days in the 90 days preceding admission was 72.0 (±22.0 days), with an average of 13.16 drinks per day (±5.70 drinks). Nearly one quarter (24.4%) of respondents reported lifetime PTSD. Three latent classes were identified: Sleep Disturbance (SD); Sleep Disturbance, Anxiety and Depression (SD/AD); and Sleep Disturbance, Anxiety and Depression, and PTSD (SD/AD/PTSD). Members of the SD/AD/PTSD group were more likely to be female and had the highest withdrawal and sleep disturbance scores of all three groups. Conclusion: Findings support the use of LCA to identify subgroups of individuals with AUDs and accompanying sleep disturbances. Class identification may provide clinicians with insight into the integrative tailoring of interventions that meet the varied needs of individuals with AUDs, accompanying comorbidities, and sleep disturbances.

Patient Acuity Related to Clinical Research: Concept Clarification and Literature Review

In research settings, clinical and research requirements contribute to nursing workload, staffing decisions, and resource allocation. The aim of this article is to define patient acuity in the context of clinical research, or research intensity, and report available instruments to measure it. The design was based on Centre for Reviews and Dissemination recommendations, including defining search terms, developing inclusion and exclusion criteria, followed by abstract review by three members of the team, thorough reading of each article by two team members, and data extraction procedures, including a quality appraisal of each article. Few instruments were available to measure research intensity. Findings provide foundational work for conceptual clarity and tool development, both of which are necessary before workforce allocation based on research intensity can occur.

A Mixed Methods Examination of Sleep Throughout the Alcohol Recovery Process Grounded in the Social Cognitive Theory: The Role of Self-Efficacy and Craving

Sleep disturbances can accompany alcohol use disorders during various phases of the disease. This analysis utilized a mixed methods approach to assess whether sleep-related beliefs and/or behavior of individuals who are alcohol dependent were associated with sleep quality both pre- and postdischarge from a clinical research facility providing inpatient alcohol rehabilitation treatment. Individuals with higher self-efficacy for sleep (SE-S) reported better sleep quality at both time points. Individuals with fewer dysfunctional beliefs about sleep had poorer sleep quality at both time points. Individuals with higher unhealthy sleep-related safety behaviors had poorer sleep quality at both time points. In a linear regression model, only the difference in SE-S scores from pre- to postdischarge (β = −.396, p = .01) and the postdischarge Penn Alcohol Craving Score (β = .283, p = .019) significantly predicted the change in sleep quality. Thus, those whose SE-S scores increased and those with lower postdischarge craving scores were more likely to experience a decrease on Pittsburgh Sleep Quality Index scores from pre- to postdischarge even after controlling for covariates. References to behavior or personal factors were often discussed during the qualitative interviews in tandem with the environment. Participants reported both (1) self-medicating anxiety with alcohol and (2) self-medicating the inability to fall asleep with alcohol. Given the success of behavioral sleep interventions in various populations and the unique potential contributions of mixed methods approaches to examine sleep and alcohol use, assessing sleep-related cognitions and behaviors of individuals with severe alcohol use disorders may be important in understanding sleep quality and subsequent relapse.

A Qualitative Exploration of Social Support during Treatment for Severe Alcohol Use Disorder and Recovery

Introduction

Severe alcohol use disorder (AUD) affects multiple aspects of an individual's life as well as their loved ones' lives. Perceived social support has the potential to help or hinder recovery efforts.

Methods

In this analysis we seek to understand the changes of social networks among individuals with severe AUD (n = 33) throughout their recovery process and the potential relationship between the quality and nature of those networks and sustained sobriety as they transition from an inpatient research facility providing rehabilitation treatment back to the community. Interviews were conducted in 2014 and 2015. We conducted in-depth thematic analysis of themes related to social support using an exploratory approach.

Results

The most common types of social support mentioned in both inpatient and outpatient settings were instrumental and emotional. Participants most frequently mentioned Alcoholics Anonymous (AA), an abstinence-based support system, as a source of support and often used the inpatient program as an exemplar when describing their ideal social networks.

Conclusion

These data provide insight into the complexity of the issues and barriers that individuals in recovery may be facing across “transition periods.” From an intervention standpoint, it may be beneficial to focus on helping people choose environments and their accompanying social contexts and networks that are most conducive to recovery. Further elucidating the concept of social support and its role in recovery could provide information on unique needs of individuals and guide clinicians in engaging patients to develop new or sustain healthy existing social networks that result in continued sobriety.

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Individuals with AUD cited varying types/sources of social support in recovery.

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Participants outlined social network-related barriers to sustained sobriety.

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Understanding social support/networks provides insight into the recovery process.

Critical Transitions: A Mixed Methods Examination of Sleep from Inpatient Alcohol Rehabilitation Treatment to the Community

Aims

This prospective, repeated measures study utilized a convergent parallel mixed methods approach to assess sleep experiences among individuals who were alcohol-dependent undergoing inpatient detoxification and treatment at a clinical research facility across the transition periods associated with the rehabilitation process: the initial adjustment to becoming an inpatient and the transition from inpatient to outpatient status.

Methods

This study included individual semi-structured interviews and quantitative measures relating to psychological distress, sleep quality, daytime sleepiness, and sleep-related beliefs and behavior (n = 33; 66.7% male). Interviews were conducted and questionnaires were administered within one week of participants’ scheduled discharge date and again four to six weeks post-discharge when they returned for a follow-up visit (or via phone).

Results

Participants self-reported significant sleep disturbances at both study time points. Of those participants with valid data at both time points (n = 28), there were no significant changes in mean scores from pre- to post-discharge with the exception of self-efficacy for sleep (SE-S) being significantly higher post-discharge. Preliminary qualitative findings suggested differences between those with ongoing sleep disturbances, those whose sleep disturbances had resolved, and those with no sleep disturbances at either time point.

Conclusions

This analysis highlights individual variation in sleep throughout the process of inpatient treatment and transition to outpatient aftercare in individuals with alcohol dependence. Collecting quantitative and qualitative data concurrently and combining emerging themes from qualitative data with quantitative analyses allowed for a more thorough examination of this relatively novel area of research and provided information that can be utilized to inform future behavioral sleep interventions.

Documenting stress in caregivers of transplantation patients: initial evidence of HPA dysregulation

There is growing evidence linking caregiver stress with an increased risk for morbidity and mortality. While the emotional and practical burden experienced by caregivers is well established, the physiological changes that may affect the caregiver's health are less understood. This study sought to compare self-reported stress, anxiety and depression along with neuroendocrine and immune markers of stress among adult caregivers of allogeneic hematopoietic stem cell transplantation patients during the acute transplant recovery period to matched non-caregivers controls. Biomarkers and self-reported data were collected at three points during the patient's HSCT: (1) before transplant, (2) after initial transplantation discharge (±7 days) and (3) 6 weeks after initial transplantation discharge. Mixed linear modeling was used to examine differences by group and time. Twenty-one caregivers and 20 controls completed all study procedures. The majority of caregivers were female (57% or 57.1%) and married (95.2%), with a mean age of 52 ± 11.4 years. Caregiver perceived stress, anxiety and depression scores were significantly higher than controls (p < 0.001) with effect sizes (ES) ranging from 1.37 to 1.80 and they did not change over time (p > 0.05) for either group. Caregivers had significantly lower serum cortisol levels than controls at both discharge (p = 0.013; ES = 0.81) and 6 weeks after discharge (p = 0.028; ES = 0.72) but exhibited no significant relationship between self-reported stress and serum cortisol. In addition, caregivers showed a significant inverse relationship between stress and epinephrine levels (r(s)=-0.654, p = 0.021). These findings support the evidence of the caregiving experience being stressful. The counter-intuitive relationship between cortisol and epinephrine might suggest dysregulation of the HPA axis and central nervous system but additional research on the physiological impact of caregiving is warranted.

Sleep disturbance, depression and pain in adults with sickle cell disease

BACKGROUND

Sleep disturbance and depression are commonly encountered in primary care. In sickle cell disease, depression is associated with pain, poor treatment compliance, and lower quality of life. The prevalence of sleep disturbance and its effect upon quality of life in adults with sickle cell disease is unknown. The goal of this study was to determine the prevalence of sleep disturbance and if it is associated with pain and depression in sickle cell disease.

METHODS

Three hundred twenty eight adults with sickle cell disease enrolled on the Bethesda Sickle Cell Cohort Study were assessed using the Pittsburgh Sleep Quality Index and Beck Depression Inventory II screening measures as a cross-sectional survey. Scores greater than 5 (Pittsburgh Sleep Quality Index) and 16 (Beck Depression Inventory II) defined sleep disturbance and depression, respectively. Clinical and laboratory parameters were also assessed.

RESULTS

The mean Pittsburgh Sleep Quality Index score was 8.4 (SD ± 4.2) indicating a 71.2% prevalence of sleep disturbance. The mean Beck Depression Inventory II score was 8.0 (SD ± 8.9). Sixty five (20.6%) participants had a score indicating depression, and half of these (10.0%) had thoughts of suicide. Both Pittsburgh Sleep Quality Index and Beck Depression Inventory II scores were significantly correlated (p < .001). The number of days with mild/moderate pain (p = .001) and a history of headaches (p = .005) were independently associated with depression by multivariate regression analysis. Patients with sleep disturbance were older (p = .002), had higher body mass index (p = .011), had more days of pain (p = .003) and more frequent severe acute painful events (emergency room visits and hospitalizations) during the previous 12 months (p < .001).

CONCLUSIONS

More than 70 percent of adults with sickle cell disease had sleep disturbance, while 21 percent showed evidence of clinical depression. Sleep disturbance and depression were correlated, and were most common among those with more frequent pain. Providers caring for adults with sickle cell disease and frequent pain should consider screening for these common co-morbidities. Additional study is needed to confirm these findings and to determine if treatments for pain, depression or sleep disturbances will improve quality of life measures in this patient population.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00011648.

Function, adjustment, quality of life and symptoms (FAQS) in allogeneic hematopoietic stem cell transplantation (HSCT) survivors: a study protocol

Background

The population of survivors following allogeneic HSCT continues to increase, and yet their experiences of recovery and long-term survivorship have not been fully characterized. This paper presents a study protocol examining over time the functional status, psychosocial adjustment, health-related quality of life, and symptom experience of survivors who have undergone allogeneic transplantation. The aims of the study are to: 1) explore the patterns of change in these health outcomes during the survivorship phase; 2) characterize subgroups of survivors experiencing adverse outcomes; and 3) examine relationships among outcomes and demographic and clinical factors (such as age, graft-versus-host disease (GVHD), and disease relapse).

Methods

In this longitudinal observational study, adults who survive a minimum of 3 years from date of allogeneic transplantation complete a series of questionnaires annually. Demographic and clinical data are collected along with a series of patient-reported outcome measures, specifically: 1) Medical Outcomes Study SF- 36; 2) Functional Assessment of Chronic Illness Therapy (FACIT) - General, 3) FACIT-Fatigue; 4) FACIT- Spiritual; 5) Psychosocial Adjustment to Illness Scale; 6) Rotterdam Symptom Checklist-Revised; and 7) Pittsburgh Sleep Quality Index.

Conclusions

This study will provide multidimensional patient-reported outcomes data to expand the understanding of the survivorship experience across the trajectory of allogeneic transplantation recovery. There are a number of inherent challenges in recruiting and retaining a diverse and representative sample of long-term transplant survivors. Study results will contribute to an understanding of outcomes experienced by transplant survivors, including those with chronic GVHD, malignant disease relapse, and other late effects following allogeneic transplantation.

Trial Registration

ClinicalTrials.gov: NCT00128960

Magnetic resonance imaging in sclerotic-type chronic graft-vs-host disease

BACKGROUND

Sclerotic-type chronic graft-vs-host disease (cGVHD) of the skin is an uncommon but potentially debilitating sequela of allogeneic hematopoietic stem cell transplantation. There is no standardized assessment measure for this form of cGVHD. Because a full-thickness incisional biopsy specimen to the level of the fascia may be needed to make a definitive histologic diagnosis of cGVHD-related fasciitis, a noninvasive technique for the assessment and monitoring of sclerotic-type cGVHD, particularly cGVHD-related fasciitis, would be of potential value.

OBSERVATIONS

Sixty-two consecutive patients with cGVHD following allogeneic hematopoietic stem cell transplantation were evaluated for sclerotic skin disease. Forty-four patients (71%) had cutaneous cGVHD, and 28 patients (45%) had evidence of sclerotic involvement based on physical examination findings. Fifteen patients agreed to undergo research magnetic resonance imaging to evaluate quantifiable changes in the dermis, subcutaneous tissue, and muscle. Among 15 patients, magnetic resonance imaging identified abnormalities in the skin in 7 (47%), subcutaneous fibrous septa in 13 (87%), deep fascia in 12 (80%), epimysium in 9 (60%), and muscle in 3 (20%).

CONCLUSIONS

Magnetic resonance imaging should be considered in the evaluation of patients with cGVHD suspected of having subcutaneous or fascial involvement. Additional studies are needed to validate this noninvasive modality for serial monitoring of disease activity and response to therapy. Trial Registration clinicaltrials.gov Identifier: NCT00331968.

Host T cells affect donor T cell engraftment and graft-versus-host disease after reduced-intensity hematopoietic stem cell transplantation

Mixed chimerism in the T cell compartment (MCT) after reduced-intensity stem cell transplantation (RIST) may influence immune repopulation with alloreactive donor T cells. We examined effects of host T cell numbers on donor T cell engraftment and recovery and on acute graft-versus-host disease (aGVHD) in a relatively homogeneous patient population with respect to residual host T cells through quantified immune depletion prior to RIST and to donor T cells by setting the allograft T cell dose of 1x10(5) CD3+ cells/kg. In this setting, 2 patterns of early donor T cell engraftment could be distinguished by day +42: (1) early and complete donor chimerism in the T cell compartment (FDCT) and (2) persistent MCT. FDCT was associated with lower residual host CD8+ T cell counts prior to transplant and aGVHD. With persistent MCT, subsequent development of aGVHD could be predicted by the direction of change in T cell donor chimerism after donor lymphocyte infusion, and no aGVHD occurred until FDCT was established. MCT did not affect recovery of donor T cell counts. These observations suggest that the relative number and alloreactivity of donor and host T cells are more important than the absolute allograft T cell dose in determining donor engraftment and aGVHD after RIST.

Effects of rhIL-7 administration in humans on in vivo expansion of naïve, memory and effector subsets of CD4+ & CD8+ T-cells

2504

Background: IL-7 has a critical and non-redundant role in T-cell lymphopoiesis and peripheral T-cell homeostasis. IL-7 administration may prove clinically valuable in conditions of disease induced (HIV) or iatrogenic T-cell depletion and for modulation of vaccine immune responses. In the first phase I study in humans, recombinant human interleukin-7 (“CYT 99–007”, Cytheris Inc., Rockville, MD) was administered subcutaneously every other day for two weeks in adults with refractory malignancies at 3, 10, 30 and 60 μg/kg/dose. Biologic activity, defined as a 50% increase over baseline of peripheral blood CD3+ T-cells, was seen at and above the 10μg/kg/dose in all patients. The kinetics of proliferation and expansion of peripheral blood T-cell subsets were analyzed. Methods: Multicolor flow cytometry was performed at baseline, 1, 2 and 3 weeks. Among CD4+ cells, the most naïve were defined as CD45RA+ /CD31+. Among CD4+ & CD8+ cells, the main naïve, memory and effector populations were defined respectively as CD45RA+/CD27+, CD45RA-/CD27+ and CD45RA-/CD27-. Within each subset, the number of cells in cycle was defined by Ki67 staining. Results: Following IL-7 therapy, there was marked proliferation of all T-cells subsets, peaking at week 1, most striking for the naive subsets with 30–70% of circulating cells induced to cycle. Proliferation rates were halved by week 2 despite continuation of treatment, coincident with the observed down-regulation of the IL-7 receptor. Cycling returned to baseline by week 3. Significant proliferation was also induced in effector and memory CD4+ and CD8+ T-cells but to a lesser magnitude, resulting in a greater net expansion of the naïve subsets, still ongoing one week after the end of treatment. Conclusions: IL-7 administration induces marked expansion of naïve, memory and effector CD4+ & CD8+ T-cells in humans. Consistent with the known down-regulation of the IL-7 receptor upon IL-7 exposure, proliferation rates decrease during the second week of treatment. rhIL-7 induced T-cell expansion may prove clinically valuable in adoptive immunotherapy as an adjunct to tumor vaccination and / or immunorestorative agent.

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Targeted pretransplant host lymphocyte depletion prior to T-cell depleted reduced-intensity allogeneic stem cell transplantation

Mixed chimaerism and graft rejection are higher after reduced-intensity allogeneic stem cell transplantation (RIST) with T-cell depleted (TCD) allografts. As host immune status before RIST affects engraftment, we hypothesized that targeted depletion of host lymphocytes prior to RIST would abrogate graft rejection and promote donor chimaerism. Lymphocyte-depleting chemotherapy was administered at conventional doses to subjects prior to RIST with the intent of decreasing CD4(+) counts to <0.05 x 10(9)cells/l. Subjects (n = 18) then received reduced-intensity conditioning followed by ex vivo TCD human leucocyte antigen-matched sibling allografts. All evaluable patients (n = 17) were engrafted; there were no late graft failures. At day +28 post-RIST, 12 patients showed complete donor chimaerism. Mixed chimaerism in the remaining five patients was associated with higher numbers of circulating host CD3(+) cells (P = 0.0032) after lymphocyte-depleting chemotherapy and was preferentially observed in T lymphoid rather than myeloid cells. Full donor chimaerism was achieved in all patients after planned donor lymphocyte infusions. These data reflect the importance of host immune status prior to RIST and suggest that targeted host lymphocyte depletion facilitates the engraftment of TCD allografts. Targeted lymphocyte depletion may permit an individualized approach to conditioning based on host immune status prior to RIST.