Design of the STRIVE-IPF trial- study of therapeutic plasma exchange, rituximab, and intravenous immunoglobulin for acute exacerbations of idiopathic pulmonary fibrosis.

BACKGROUND: Acute exacerbations of idiopathic pulmonary fibrosis (AE-IPF) affect a significant proportion of patients with IPF. There are limited data to inform therapeutic strategies for AE-IPF, despite its high mortality. We discuss the rationale and design of STRIVE-IPF, a randomized, multi-center, open-label Phase IIb clinical trial to determine the efficacy of combined therapeutic plasma exchange (TPE), rituximab, and intravenous immunoglobulin (IVIG), in comparison to treatment as usual (TAU), among patients with acute IPF exacerbations. METHODS: The STRIVE-IPF trial will randomize 51 patients among five sites in the United States. The inclusion criteria have been designed to select a study population with AE-IPF, as defined by American Thoracic Society criteria, while excluding patients with an alternative cause for a respiratory decompensation. The primary endpoint of this trial is six-month survival. Secondary endpoints include supplement oxygen requirement and six-minute walk distance which will be assessed immediately prior to treatment and after completion of therapy on day 19, as well as at periodic subsequent visits. DISCUSSION: The experimental AE-IPF therapy proposed in this clinical trial was adapted from treatment regimens used in other antibody-mediated diseases. The regimen is initiated with TPE, which is expected to rapidly reduce circulating autoantibodies, followed by rituximab to reduce B-cells and finally IVIG, which likely has multiple effects, including affecting feedback inhibition of residual B-cells by Fc receptor occupancy. We have reported potential benefits of this experimental therapy for AE-IPF in previous anecdotal reports. This clinical trial has the potential to profoundly affect current paradigms and treatment approaches to patients with AE-IPF. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03286556.

A multidimensional classifier to support lung transplant referral in patients with pulmonary fibrosis.

BACKGROUND: Lung transplantation remains the sole curative option for patients with idiopathic pulmonary fibrosis (IPF), but donor organs remain scarce, and many eligible patients die before transplant. Tools to optimize the timing of transplant referrals are urgently needed. METHODS: Least absolute shrinkage and selection operator was applied to clinical and proteomic data generated as part of a prospective cohort study of interstitial lung disease (ILD) to derive clinical, proteomic, and multidimensional logit models of near-term death or lung transplant within 18 months of blood draw. Model-fitted values were dichotomized at the point of maximal sensitivity and specificity, and decision curve analysis was used to select the best-performing classifier. We then applied this classifier to independent IPF and non-IPF ILD cohorts to determine test performance characteristics. Cohorts were restricted to patients aged ≤72 years with body mass index 18 to 32 to increase the likelihood of transplant eligibility. RESULTS: IPF derivation, IPF validation, and non-IPF ILD validation cohorts consisted of 314, 105, and 295 patients, respectively. A multidimensional model comprising 2 clinical variables and 20 proteins outperformed stand-alone clinical and proteomic models. Following dichotomization, the multidimensional classifier predicted near-term outcome with 70% sensitivity and 92% specificity in the IPF validation cohort and 70% sensitivity and 80% specificity in the non-IPF ILD validation cohort. CONCLUSIONS: A multidimensional classifier of near-term outcomes accurately discriminated this end-point with good test performance across independent IPF and non-IPF ILD cohorts. These findings support refinement and prospective validation of this classifier in transplant-eligible individuals.

Impact of Acute Exacerbation of Idiopathic Pulmonary Fibrosis on Lung Transplant Outcomes.

BACKGROUND: Acute exacerbations of idiopathic pulmonary fibrosis (AE-IPF) are acute, significant respiratory deteriorations in patients with IPF and can lead to increased morbidity and mortality. It remains unclear how AE-IPF impacts lung transplant (LTX) outcomes. METHODS: All adult patients who were listed for LTX between July 2005 and October 2020 at the Loyola University Medical Center with a diagnosis of IPF were included. Pretransplant characteristics and posttransplant outcomes were gathered via retrospective chart review. The primary outcome was short- and long-term survival for patients transplanted during stable IPF versus those with AE-IPF. RESULTS: One hundred fifty-nine patients were included in this study, 17.6% of whom were transplanted during AE-IPF. AE-IPF patients were more likely to have higher oxygen needs pretransplant, have higher lung allocation score, and were more likely to be intubated or be on extracorporeal membrane oxygenation as compared with stable IPF patients. Survival by AE status at transplant did not differ at 90 d or 1 y posttransplantation. There were also no significant differences in rates of severe primary graft dysfunction or acute rejection within 1 y. CONCLUSIONS: Patients with AE-IPF were more likely to have higher oxygenation requirements and higher lung allocation score at the time of LTX than those with stable IPF. Despite this, there were no differences in survival at 90 d, 1 y, or 3 y, or differences in incidence of severe primary graft dysfunction or acute cellular rejection. Transplantation of patients with AE-IPF has clinical outcomes comparable with transplantation of patients with stable IPF. This contrasts with previous studies examining LTX in patients with AE-IPF.

Lung transplantation for lymphangioleiomyomatosis.

Lymphangioleiomyomatosis (LAM) is a rare cystic lung disease, associated with respiratory symptoms of dyspnea and spontaneous pneumothorax, along with various extra-thoracic manifestations. Often a progressive disease, albeit slowly, patients can develop chronic and severe respiratory failure and require supplemental oxygen. Lung transplantation (LTX) can offer improved duration and quality of life for patients with end-stage lung disease due to LAM. There are several unique considerations for LTX in LAM patients, and disease-specific complications of LAM prior to LTX can affect management decisions. Furthermore, there are several possible post-transplant issues specific to LAM. In this review, we discuss evaluation and management, disease-specific complications (both pre- and post-transplant), and outcomes for LAM patients undergoing lung transplantation.

A survey of use of mTOR inhibitors in patients with lymphangioleiomyomatosis listed for lung transplant.

BACKGROUND: Lymphangioleiomyomatosis (LAM) is an uncommon indication for lung transplantation. The use of mechanistic target of rapamycin (mTOR) inhibitors, which are the mainstay of treatment in progressive LAM, in patients awaiting lung transplant is controversial. We sought to examine worldwide practice patterns in use of mTOR inhibitors in LAM patients on the lung transplant waiting list. METHODS: We designed and disseminated an online survey about institution-specific practice patterns, particularly regarding listing LAM patients for lung transplant and use of mTOR inhibitors in those patients on the transplant waitlist. RESULTS: Of the 49 unique respondent programs, 83.6% had previously listed a LAM patient for lung transplant. Thirteen centers allowed patients to continue on mTOR inhibitor until time of lung transplant. None of those centers reported any complications or deaths attributable to mTOR inhibitor adverse effects. CONCLUSION: There exists significant variability in practice patterns concerning the use of mTOR inhibitors in LAM patients on the lung transplant waiting list. Our survey suggests favorable outcomes for those patients that did continue mTOR inhibitor up to time of transplant. Further data regarding the risk of anastomotic complication with use of mTOR inhibitors in the pre-transplant period would help provide clarity in this debate.

Disparities in Lung Transplant among Patients with Idiopathic Pulmonary Fibrosis: An Analysis of the IPF-PRO Registry.

Rationale: Lung transplant offers the potential to extend life for patients with idiopathic pulmonary fibrosis (IPF); yet, this therapeutic modality is only available to a small proportion of patients. Objectives: To identify clinical characteristics and social determinants of health that differentially associate with lung transplant compared with death in patients with IPF. Methods: We evaluated data from the Idiopathic Pulmonary Fibrosis Prospective Outcomes (IPF-PRO) Registry, a multicenter U.S. registry of patients with IPF that was diagnosed or confirmed at the enrolling center in the previous 6 months. Patients were enrolled between June 2014 and October 2018. Patients who were listed for lung transplant were not eligible to enroll in the registry, but patients could be listed for transplant after enrollment. We performed a multivariable time-to-event analysis incorporating competing risks methodology to examine differential associations between prespecified covariates and the risk of lung transplant versus death. Covariates included factors related to lung transplant eligibility, clinical characteristics of IPF, and social determinants of health. Covariates were modeled as time independent or time dependent as appropriate. Results: Among 955 patients with IPF, event rates of lung transplant and death were 7.4% and 16.3%, respectively, at 2 years. Covariates with the strongest differential association were age, median zip code income, and enrollment at a center with a lung transplant program. Lung transplant was less likely (hazard ratio [HR], 0.13 [95% confidence interval (CI), 0.06-0.28] per 5-yr increase) and death more likely (HR, 1.41 [95% CI, 1.22-1.64] per 5-yr increase) among those older than 70 years of age. Higher median zip code income was associated with lung transplant (HR, 1.22 [95% CI, 1.13-1.31] per $10,000 increase) but not death (HR, 0.99 [95% CI, 0.94-1.04] per $10,000 increase). Enrollment at a center with a lung transplant program was associated with lung transplant (HR, 4.31 [95% CI, 1.76-10.54]) but not death (HR, 0.99 [95% CI, 0.69-1.43]). Oxygen use with activity was associated with both lung transplant and death, but more strongly with lung transplant. A higher number of comorbidities was associated with an increased likelihood of death but not lung transplant. Conclusions: For patients in the Idiopathic Pulmonary Fibrosis Prospective Outcomes Registry, median zip code income and access to a lung transplant center differentially impact the risk of lung transplant compared with death, regardless of disease severity measures or other transplant eligibility factors. Interventions are needed to mitigate inequalities in lung transplantation based on socioeconomic status. Clinical trial registered with www.clinicaltrials.gov (NCT01915511).

Benign tumors in TSC are amenable to treatment by GD3 CAR T cells in mice.

Mutations underlying disease in tuberous sclerosis complex (TSC) give rise to tumors with biallelic mutations in TSC1 or TSC2 and hyperactive mammalian target of rapamycin complex 1 (mTORC1). Benign tumors might exhibit de novo expression of immunogens, targetable by immunotherapy. As tumors may rely on ganglioside D3 (GD3) expression for mTORC1 activation and growth, we compared GD3 expression in tissues from patients with TSC and controls. GD3 was overexpressed in affected tissues from patients with TSC and also in aging Tsc2+/- mice. As GD3 overexpression was not accompanied by marked natural immune responses to the target molecule, we performed preclinical studies with GD3 chimeric antigen receptor (CAR) T cells. Polyfunctional CAR T cells were cytotoxic toward GD3-overexpressing targets. In mice challenged with Tsc2-/- tumor cells, CAR T cells substantially and durably reduced the tumor burden, correlating with increased T cell infiltration. We also treated aged Tsc2+/- heterozygous (>60 weeks) mice that carry spontaneous Tsc2-/- tumors with GD3 CAR or untransduced T cells and evaluated them at endpoint. Following CAR T cell treatment, the majority of mice were tumor free while all control animals carried tumors. The outcomes demonstrate a strong treatment effect and suggest that targeting GD3 can be successful in TSC.

Effect of Antimicrobial Therapy on Respiratory Hospitalization or Death in Adults With Idiopathic Pulmonary Fibrosis: The CleanUP-IPF Randomized Clinical Trial.

Importance: Alteration in lung microbes is associated with disease progression in idiopathic pulmonary fibrosis. Objective: To assess the effect of antimicrobial therapy on clinical outcomes. Design, Setting, and Participants: Pragmatic, randomized, unblinded clinical trial conducted across 35 US sites. A total of 513 patients older than 40 years were randomized from August 2017 to June 2019 (final follow-up was January 2020). Interventions: Patients were randomized in a 1:1 allocation ratio to receive antimicrobials (n = 254) or usual care alone (n = 259). Antimicrobials included co-trimoxazole (trimethoprim 160 mg/sulfamethoxazole 800 mg twice daily plus folic acid 5 mg daily, n = 128) or doxycycline (100 mg once daily if body weight <50 kg or 100 mg twice daily if ≥50 kg, n = 126). No placebo was administered in the usual care alone group. Main Outcomes and Measures: The primary end point was time to first nonelective respiratory hospitalization or all-cause mortality. Results: Among the 513 patients who were randomized (mean age, 71 years; 23.6% women), all (100%) were included in the analysis. The study was terminated for futility on December 18, 2019. After a mean follow-up time of 13.1 months (median, 12.7 months), a total of 108 primary end point events occurred: 52 events (20.4 events per 100 patient-years [95% CI, 14.8-25.9]) in the usual care plus antimicrobial therapy group and 56 events (18.4 events per 100 patient-years [95% CI, 13.2-23.6]) in the usual care group, with no significant difference between groups (adjusted HR, 1.04 [95% CI, 0.71-1.53; P = .83]. There was no statistically significant interaction between the effect of the prespecified antimicrobial agent (co-trimoxazole vs doxycycline) on the primary end point (adjusted HR, 1.15 [95% CI 0.68-1.95] in the co-trimoxazole group vs 0.82 [95% CI, 0.46-1.47] in the doxycycline group; P = .66). Serious adverse events occurring at 5% or greater among those treated with usual care plus antimicrobials vs usual care alone included respiratory events (16.5% vs 10.0%) and infections (2.8% vs 6.6%); adverse events of special interest included diarrhea (10.2% vs 3.1%) and rash (6.7% vs 0%). Conclusions and Relevance: Among adults with idiopathic pulmonary fibrosis, the addition of co-trimoxazole or doxycycline to usual care, compared with usual care alone, did not significantly improve time to nonelective respiratory hospitalization or death. These findings do not support treatment with these antibiotics for the underlying disease. Trial Registration: ClinicalTrials.gov Identifier: NCT02759120.

Immunosuppressive strategies in lung transplantation.

Lung transplantation is a viable option for those with end-stage lung disease which is evidenced by the continued increase in the number of lung transplantations worldwide. However, patients and clinicians are constantly faced with acute and chronic rejection, infectious complications, drug toxicities, and malignancies throughout the lifetime of the lung transplant recipient. Conventional maintenance immunosuppression therapy consisting of a calcineurin inhibitor (CNI), anti-metabolite, and corticosteroids have become the standard regimen but newer agents and modalities continue to be developed. Here we will review induction agents, maintenance immunosuppressives, adjunctive therapies and other strategies to improve long-term outcomes.

Adoptive T-Cell Transfer to Treat Lymphangioleiomyomatosis.

Patients with lymphangioleiomyomatosis (LAM) develop pulmonary cysts associated with neoplastic, smooth muscle-like cells that feature neuroendocrine cell markers. The disease preferentially affects premenopausal women. Existing therapeutics do not cure LAM. As gp100 is a diagnostic marker expressed by LAM lesions, we proposed to target this immunogenic glycoprotein using TCR transgenic T cells. To reproduce the genetic mutations underlying LAM, we cultured Tsc2-/- kidney tumor cells from aged Tsc2 heterozygous mice and generated a stable gp100-expressing cell line by lentiviral transduction. T cells were isolated from major histocompatibility complex-matched TCR transgenic pmel-1 mice to measure cytotoxicity in vitro, and 80% cytotoxicity was observed within 48 hours. Antigen-specific cytotoxicity was likewise observed using pmel-1 TCR-transduced mouse T cells, suggesting that transgenic T cells may likewise be useful to treat LAM in vivo. On intravenous injection, slow-growing gp100+ LAM-like cells formed lung nodules that were readily detectable in severe combined immunodeficient/beige mice. Adoptive transfer of gp100-reactive but not wild-type T cells into mice significantly shrunk established lung tumors, even in the absence of anti-PD-1 therapy. These results demonstrate the treatment potential of adoptively transferred T cells to eliminate pulmonary lesions in LAM.

Associations between Patient-reported Outcomes and Death or Lung Transplant in Idiopathic Pulmonary Fibrosis. Data from the Idiopathic Pulmonary Fibrosis Prospective Outcomes Registry.

Rationale: Progression of idiopathic pulmonary fibrosis (IPF) is accompanied by worsening of symptoms, exercise capacity, and health-related quality of life. However, the utility of patient-reported outcomes as predictors of mortality remains uncertain.Objectives: To assess whether patient-reported outcomes are independently associated with mortality beyond clinical risk factors in patients with IPF.Methods: Data from the observational IPF Prospective Outcomes Registry were used to examine associations between patient-reported outcomes at enrollment and the composite outcome of death or lung transplant in the following year. Associations were examined using univariable models and models adjusted for age and clinical variables that have been associated with death or lung transplant in patients with IPF in this cohort (oxygen use, forced vital capacity % predicted, and diffusing capacity of the lungs for carbon monoxide % predicted at enrollment).Results: Among 662 patients, 45 died and 12 underwent lung transplant over 1 year. In the model adjusted for age and clinical variables that were associated with death or lung transplant, worse scores on the St. George's Respiratory Questionnaire (SGRQ) total score (hazard ratio [HR], 1.22 [95% confidence interval (CI), 1.01-1.48] per 10-point increase), SGRQ activity score (HR, 1.25 [95% CI, 1.02-1.54] per 10-point increase) and SGRQ symptoms score (HR, 1.17 [95% CI, 1.01-1.36] per 10-point increase) were associated with death or lung transplant over 1 year.Conclusions: Patient-reported outcomes that assess symptoms and physical activity are independently associated with mortality in patients with IPF.

Clinical outcomes and survival following lung transplantation in patients with pulmonary Langerhans cell histiocytosis.

BACKGROUND AND OBJECTIVE: Disease-specific outcomes following lung transplantation (LT) in patients with pulmonary Langerhans cell histiocytosis (PLCH) are not well established. We queried the Organ Procurement and Transplantation Network database to identify adult PLCH patients who had undergone LT in the United States. METHODS: Overall survival data were analysed with Kaplan-Meier curves. Cox proportional hazard model was used to determine the effect of demographic, clinical and physiological variables on post-transplant survival. RESULTS: A total of 87 patients with PLCH underwent LT in the United States between October 1987 and June 2017, accounting for 0.25% of the total LT during this period. The mean age at LT for PLCH patients was 49 years (range: 19-67 years), with a near equal gender distribution. Bilateral sequential LT was performed in 71 patients (82%). Pulmonary hypertension was present in 85% of patients, with a mean pulmonary artery pressure of 38.5 ± 14.1 mm Hg. The mean pre-transplant forced expiratory volume in 1 s (FEV1 ) was 41 ± 21% predicted and the mean 6-min walk distance was 221 ± 111 m. Median post-LT survival for PLCH patients was comparable to patients with other lung diseases (5.1 vs 5.5 years, P = 0.76). The actuarial Kaplan-Meier post-LT survival for PLCH patients was 85%, 65%, 49% and 22% at 1, 3, 5 and 10 years, respectively. Female sex (hazard ratio (HR): 0.40, 95% CI: 0.22-0.72), pre-transplant serum bilirubin (HR: 1.66, 95% CI: 1.23-2.26) and serum creatinine (HR: 4.03, 95% CI: 1.01-14.76) were independently associated with post-LT mortality in our cohort. CONCLUSION: Post-LT survival in patients with PLCH is similar to patients with other lung diseases and is significantly affected by patient gender.

Initial skin cancer screening for solid organ transplant recipients in the United States: Delphi method development of expert consensus guidelines.

Skin cancer is the most common malignancy affecting solid organ transplant recipients (SOTR), and SOTR experience increased skin cancer-associated morbidity and mortality. There are no formal multidisciplinary guidelines for skin cancer screening after transplant, and current practices are widely variable. We conducted three rounds of Delphi method surveys with a panel of 84 U.S. dermatologists and transplant physicians to establish skin cancer screening recommendations for SOTR. The transplant team should risk stratify SOTR for screening, and dermatologists should perform skin cancer screening by full-body skin examination. SOTR with a history of skin cancer should continue regular follow-up with dermatology for skin cancer surveillance. High-risk transplant patients include thoracic organ recipients, SOTR age 50 and above, and male SOTR. High-risk Caucasian patients should be screened within 2 years after transplant, all Caucasian, Asian, Hispanic, and high-risk African American patients should be screened within 5 years after transplant. No consensus was reached regarding screening for low-risk African American SOTR. We propose a standardized approach to skin cancer screening in SOTR based on multidisciplinary expert consensus. These guidelines prioritize and emphasize the need for screening for SOTR at greatest risk for skin cancer.

Clinical outcomes and survival following lung transplantation in patients with lymphangioleiomyomatosis.

BACKGROUND: The primary aim of our study was to derive disease-specific outcomes following lung transplantation (LT) in patients with lymphangioleiomyomatosis (LAM). METHODS: We queried the Organ Procurement and Transplant Network database to identify LAM patients that have undergone LT in the United States. The overall survival was analyzed with Kaplan-Meier curves. Survival estimates between subgroups of interest were compared using the log-rank method. Cox proportional hazard models were employed to determine the pre-transplant variables that impact post-LT survival. RESULTS: One hundred and thirty-eight women with LAM underwent LT at 31 centers between January 2003 and June 2017. The median age at listing and transplant was 44 (IQR: 36-51) and 45 (IQR: 38-52) years, respectively. The median time spent on the LT waitlist was 257 (IQR: 85-616) days. The majority of the patients (109/134, 81%) received bilateral sequential LT. The median ischemic time was 4.9 (IQR: 4.1-6.1) hours. The actuarial Kaplan-Meier survival following LT for LAM patients at 1-, 5-, and 10 years was 94%, 73% and 56%, respectively. The post-LT survival was significantly better in LAM than in other lung diseases (10-year survival 56% vs. 32%, p < 0.01), and this advantage persisted after age- and gender-matched analysis (10-year survival 54% vs. 37%, p < 0.01). Pre-transplant parameters, such as the presence of pulmonary hypertension, six-minute walk distance, age at transplant, ischemic time during transplant, or type of transplant (single vs bilateral sequential LT), did not affect post-transplant survival. CONCLUSIONS: The median survival after LT in LAM is 12 years and is substantially better than in other lung diseases.

A Phase II Clinical Trial of an Aromatase Inhibitor for Postmenopausal Women with Lymphangioleiomyomatosis.

RATIONALE: Lymphangioleiomyomatosis (LAM) is a progressive cystic lung disease that predominantly affects women and can worsen with pregnancy, estrogen treatment, and the menstrual cycle, suggesting an important role for estrogen in disease pathogenesis. OBJECTIVES: To assess the efficacy and safety of the aromatase inhibitor letrozole in the treatment of LAM. METHODS: Seventeen postmenopausal women with LAM were enrolled in this phase II trial and randomized to receive letrozole 2.5 mg daily (n = 9) or placebo (n = 8) for a period of 12 months. Five patients in each group were also taking sirolimus at baseline and remained on the drug throughout the treatment period. Lung function, exercise capacity, quality of life, and serum vascular endothelial growth factor D (VEGF-D) were measured at baseline and at 3-month intervals. RESULTS: Fifteen patients completed the study. Two patients withdrew. There were no differences in adverse events in the letrozole and placebo groups. The target enrollment of 25 patients per arm was not met, so the efficacy of letrozole could not be assessed as planned. After adjusting for sirolimus use, we found that the rate of change in FEV1 for all subjects was -3 ± 3 ml/mo (P = 0.4), and for serum VEGF-D, the rate of change was -0.024 ± 0.009 pg/ml/mo (P = 0.015), showing a steeper decline in the letrozole group (-0.029 ± 0.013; P = 0.025). All patients who were taking sirolimus had a reduction in VEGF-D levels from baseline to the last visit, compared with only half of the patients who were not taking sirolimus. In a post hoc analysis, eight matched letrozole-treated-placebo-treated pairs were constructed, six of which demonstrated better FEV1 improvement for the letrozole-treated patients. CONCLUSIONS: Letrozole treatment appears to be safe and well tolerated in postmenopausal patients with LAM, including those taking sirolimus. Enrollment in this trial was compromised by the publication of an effective treatment (sirolimus) in the same month as the study opened, resulting in limited power to detect treatment effects. Post hoc matched pairs exploration studies provide tentative support for additional studies of letrozole in LAM. Considering the reduced rate of lung function decline in postmenopausal patients, future studies will likely require enhanced study designs, such as selective enrollment of those with prognostic biomarkers predictive of decline. Clinical trial registered with www.clinicaltrials.gov (NCT01353209).

Alpha-N-acetyl-neuraminide alpha-2,8-sialyltransferase 1 can support immune responses toward tumors overexpressing ganglioside D3 in mice.

An immunotherapeutic strategy is discussed supporting anti-tumor activity toward malignancies overexpressing ganglioside D3. GD3 can be targeted by NKT cells when derived moieties are presented in the context of CD1d. NKT cells can support anti-tumor responses by secreting inflammatory cytokines and through cytotoxicity toward CD1d+GD3+ tumors. To overexpress GD3, we generated expression vector DNA and an adenoviral vector encoding the enzyme responsible for generating GD3 from its ubiquitous precursor GM3. We show that DNA encoding α-N-acetyl-neuraminide α-2,8-sialyltransferase 1 (SIAT8) introduced by gene gun vaccination in vivo leads to overexpression of GD3 and delays tumor growth. Delayed tumor growth is dependent on CD1d expression by host immune cells, as shown in experiments engaging CD1d knockout mice. A trend toward greater NKT cell populations among tumor-infiltrating lymphocytes is associated with SIAT8 vaccination. A single adenoviral vaccination introduces anti-tumor activity similarly to repeated vaccination with naked DNA. Here, greater NKT tumor infiltrates were accompanied by marked overexpression of IL-17 in the tumor, later switching to IL-4. Our results suggest that a single intramuscular adenoviral vaccination introduces overexpression of GD3 by antigen-presenting cells at the injection site, recruiting NKT cells that provide an inflammatory anti-tumor environment. We propose adenoviral SIAT8 (AdV-SIAT8) can slow the growth of GD3 expressing tumors in patients.