Training Death Investigators to Identify Decedents' Sexual Orientation and Gender Identity: A Feasibility Study.

ABSTRACT: There is growing impetus within mortality surveillance to identify decedents' sexual orientation and gender identity (SOGI), but key personnel to this effort (eg, death investigators) are not currently trained to collect SOGI information. To address this gap, we developed a training for death investigators on this topic and tested its feasibility with 114 investigators in 3 states. Participants completed pretraining and posttraining questionnaires that measured 4 perceived outcomes: training relevance, success of delivery, adequacy for future use, and likelihood of future use. Overall, strongly positive responses affirmed the training's relevance, success of delivery, and adequacy for future use. Responses about attempting to identify the decedent's SOGI in future cases were not quite as positive, with close to 80% of the participants saying that they were at least "somewhat likely" to collect this information. Despite design limitations, the study results support the feasibility of training death investigators to gather SOGI information. Although not systematically assessed in the study, investigators' positive endorsement of training outcomes seemed higher in training sites where leadership strongly supported SOGI identification, suggesting that the role of leadership may be key to encouraging SOGI identification among death investigators.

Collecting Sexual Orientation and Gender Identity Information at Death.

Currently, no US jurisdiction or agency routinely or systematically collects information about individuals' sexual orientation and gender identity (SOGI) at the time of death. As a result, little is known about causes of death in people having a minority sexual orientation or gender identity. These knowledge gaps have long impeded identification of mortality disparities in sexual and gender minority populations and hampered the development of targeted public health interventions and prevention strategies. We offer observations about the possibilities and challenges of collecting and reporting accurate postmortem SOGI information on the basis of our past four years of working with death investigators, coroners, and medical examiners. This work was located primarily in New York, New York, and has extended from January 2015 to the present. Drawing on our experiences, we make recommendations for future efforts to include SOGI among the standard demographic variables used to characterize individuals at death.

Trefoil factor 2 negatively regulates type 1 immunity against Toxoplasma gondii.

IL-12-mediated type 1 inflammation confers host protection against the parasitic protozoan Toxoplasma gondii. However, production of IFN-γ, another type 1 inflammatory cytokine, also drives lethality from excessive injury to the intestinal epithelium. As mechanisms that restore epithelial barrier function following infection remain poorly understood, this study investigated the role of trefoil factor 2 (TFF2), a well-established regulator of mucosal tissue repair. Paradoxically, TFF2 antagonized IL-12 release from dendritic cells (DCs) and macrophages, which protected TFF2-deficient (TFF2(-/-)) mice from T. gondii pathogenesis. Dysregulated intestinal homeostasis in naive TFF2(-/-) mice correlated with increased IL-12/23p40 levels and enhanced T cell recruitment at baseline. Infected TFF2(-/-) mice displayed low rates of parasite replication and reduced gut immunopathology, whereas wild-type (WT) mice experienced disseminated infection and lethal ileitis. p38 MAPK activation and IL-12p70 production was more robust from TFF2(-/-)CD8+ DC compared with WT CD8+ DC and treatment of WT DC with rTFF2 suppressed TLR-induced IL-12/23p40 production. Neutralization of IFN-γ and IL-12 in TFF2(-/-) animals abrogated resistance shown by enhanced parasite replication and infection-induced morbidity. Hence, TFF2 regulated intestinal barrier function and type 1 cytokine release from myeloid phagocytes, which dictated the outcome of oral T. gondii infection in mice.

Toxoplasma gondii rhoptry kinase ROP16 activates STAT3 and STAT6 resulting in cytokine inhibition and arginase-1-dependent growth control.

The ROP16 kinase of Toxoplasma gondii is injected into the host cell cytosol where it activates signal transducer and activator of transcription (STAT)-3 and STAT6. Here, we generated a ROP16 deletion mutant on a Type I parasite strain background, as well as a control complementation mutant with restored ROP16 expression. We investigated the biological role of the ROP16 molecule during T. gondii infection. Infection of mouse bone marrow-derived macrophages with rop16-deleted (ΔROP16) parasites resulted in increased amounts of IL-12p40 production relative to the ROP16-positive RH parental strain. High level IL-12p40 production in ΔROP16 infection was dependent on the host cell adaptor molecule MyD88, but surprisingly was independent of any previously recognized T. gondii triggered pathway linking to MyD88 (TLR2, TLR4, TLR9, TLR11, IL-1ß and IL-18). In addition, ROP16 was found to mediate the suppressive effects of Toxoplasma on LPS-induced cytokine synthesis in macrophages and on IFN-γ-induced nitric oxide production by astrocytes and microglial cells. Furthermore, ROP16 triggered synthesis of host cell arginase-1 in a STAT6-dependent manner. In fibroblasts and macrophages, failure to induce arginase-1 by ΔROP16 tachyzoites resulted in resistance to starvation conditions of limiting arginine, an essential amino acid for replication and virulence of this parasite. ΔROP16 tachyzoites that failed to induce host cell arginase-1 displayed increased replication and dissemination during in vivo infection. We conclude that encounter between Toxoplasma ROP16 and the host cell STAT signaling cascade has pleiotropic downstream effects that act in multiple and complex ways to direct the course of infection.

Growth Differentiation Factor-15 Predicts Mortality and Heart Failure Exacerbation But Not Ventricular Arrhythmias in Patients With Cardiomyopathy.

Background Heart failure (HF) has been increasing in prevalence, and a need exists for biomarkers with improved predictive and prognostic ability. GDF-15 (growth differentiation factor-15) is a novel biomarker associated with HF mortality, but no serial studies of GDF-15 have been conducted. This study aimed to investigate the association between GDF-15 levels over time and the occurrence of ventricular arrhythmias, HF hospitalizations, and all-cause mortality. Methods and Results We used a retrospective case-control design to analyze 148 patients with ischemic and nonischemic cardiomyopathies and primary prevention implantable cardioverter-defibrillator (ICD) from the PROSe-ICD (Prospective Observational Study of the ICD in Sudden Cardiac Death Prevention) cohort. Patients had blood drawn every 6 months and after each appropriate ICD therapy and were followed for a median follow-up of 4.6 years, between 2005 to 2019. We compared serum GDF-15 levels within ±90 days of an event among those with a ventricular tachycardia/fibrillation event requiring ICD therapies and those hospitalized for decompensated HF. A comparator/control group comprised patients with GDF-15 levels available during 2-year follow-up periods without events. Median follow-up was 4.6 years in the 148 patients studied (mean age 58±12, 27% women). The HF cohort had greater median GDF-15 values within 90 days (1797 pg/mL) and 30 days (2039 pg/mL) compared with the control group (1062 pg/mL, both P<0.0001). No difference was found between the ventricular tachycardia/fibrillation subgroup within 90 days (1173 pg/mL, P=0.60) or 30 days (1173 pg/mL, P=0.78) and the control group. GDF-15 was also significantly predictive of mortality (hazard ratio, 3.17 [95% CI, 2.33-4.30]). Conclusions GDF-15 levels are associated with HF hospitalization and mortality but not ventricular arrhythmic events.

An inside job: hacking into Janus kinase/signal transducer and activator of transcription signaling cascades by the intracellular protozoan Toxoplasma gondii.

The intracellular protozoan Toxoplasma gondii is well known for its skill at invading and living within host cells. New discoveries are now also revealing the astounding ability of the parasite to inject effector proteins into the cytoplasm to seize control of the host cell. This review summarizes recent advances in our understanding of one such secretory protein called ROP16. This molecule is released from rhoptries into the host cell during invasion. The ROP16 molecule acts as a kinase, directly activating both signal transducer and activator of transcription 3 (STAT3) and STAT6 signaling pathways. In macrophages, an important and preferential target cell of parasite infection, the injection of ROP16 has multiple consequences, including downregulation of proinflammatory cytokine signaling and macrophage deviation to an alternatively activated phenotype.

Mouse neutrophils are professional antigen-presenting cells programmed to instruct Th1 and Th17 T-cell differentiation.

Neutrophils play a major role in the innate immune system and are normally considered to be short-lived effector cells that exert anti-microbial activity and sometimes immunopathology. Here, we show that these cells possess an additional function as professional antigen-presenting cells capable of priming a T(h)1- and T(h)17-acquired immune response. Using flow cytometry, fluorescence microscopy and western blotting, we show that mouse neutrophils express MHC class II and co-stimulatory molecules CD80 and CD86 after T-cell co-incubation. Neutrophils pulsed with ovalbumin (OVA) process and present peptide antigen to OVA-specific T cells in an MHC class II-dependent manner. Importantly, we demonstrate that neutrophils can prime antigen-specific T(h)1 and T(h)17 immune responses even without the addition of exogenous cytokines to cell cultures.

Toxoplasma gondii prevents chromatin remodeling initiated by TLR-triggered macrophage activation.

Macrophages infected with the opportunistic protozoan Toxoplasma gondii are unable to up-regulate many proinflammatory cytokine genes, including TNF (TNF-alpha), upon stimulation with LPS and other TLR ligands. In this study, we examined the influence of T. gondii on transcription factors associated with TNF-alpha transcription, as well as phosphorylation and acetylation of histone H3 at distal and proximal regions of the TNF-alpha promoter. During LPS stimulation, we found that Toxoplasma blocks nuclear accumulation of transcription factor c-Jun, but not that of cAMP response element-binding protein or NF-kappaB. However, chromatin immunoprecipitation studies revealed that binding of all of these transcription factors to the TNF promoter was decreased by T. gondii infection. Furthermore, the parasite blocked LPS-induced Ser(10) phosphorylation and Lys(9)/Lys(14) acetylation of histone H3 molecules associated with distal and proximal regions of the TNF-alpha promoter. Our results show that Toxoplasma inhibits TNF-alpha transcription by interfering with chromatin remodeling events required for transcriptional activation at the TNF promoter, revealing a new mechanism by which a eukaryotic pathogen incapacitates proinflammatory cytokine production during infection.

A new electrocardiogram marker to identify patients at low risk for ventricular tachyarrhythmias: sum magnitude of the absolute QRST integral.

OBJECTIVE: We proposed and tested a novel electrocardiogram marker of risk of ventricular arrhythmias (VAs). METHODS: Digital orthogonal electrocardiograms were recorded at rest before implantable cardioverter-defibrillator (ICD) implantation in 508 participants of a primary prevention ICDs prospective cohort study (mean ± SD age, 60 ± 12 years; 377 male [74%]). The sum magnitude of the absolute QRST integral in 3 orthogonal leads (SAI QRST) was calculated. A derivation cohort of 128 patients was used to define a cutoff; a validation cohort (n = 380) was used to test a predictive value. RESULTS: During a mean follow-up of 18 months, 58 patients received appropriate ICD therapies. The SAI QRST was lower in patients with VA (105.2 ± 60.1 vs 138.4 ± 85.7 mV ms, P = .002). In the Cox proportional hazards analysis, patients with SAI QRST not exceeding 145 mV ms had about 4-fold higher risk of VA (hazard ratio, 3.6; 95% confidence interval, 1.96-6.71; P < .0001) and a 6-fold higher risk of monomorphic ventricular tachycardia (hazard ratio, 6.58; 95% confidence interval, 1.46-29.69; P = .014), whereas prediction of polymorphic ventricular tachycardia or ventricular fibrillation did not reach statistical significance. CONCLUSION: High SAI QRST is associated with low risk of sustained VA in patients with structural heart disease.

CinE caRdiac magneTic resonAnce to predIct veNTricular arrhYthmia (CERTAINTY).

Better models to identify individuals at low risk of ventricular arrhythmia (VA) are needed for implantable cardioverter-defibrillator (ICD) candidates to mitigate the risk of ICD-related complications. We designed the CERTAINTY study (CinE caRdiac magneTic resonAnce to predIct veNTricular arrhYthmia) with deep learning for VA risk prediction from cine cardiac magnetic resonance (CMR). Using a training cohort of primary prevention ICD recipients (n = 350, 97 women, median age 59 years, 178 ischemic cardiomyopathy) who underwent CMR immediately prior to ICD implantation, we developed two neural networks: Cine Fingerprint Extractor and Risk Predictor. The former extracts cardiac structure and function features from cine CMR in a form of cine fingerprint in a fully unsupervised fashion, and the latter takes in the cine fingerprint and outputs disease outcomes as a cine risk score. Patients with VA (n = 96) had a significantly higher cine risk score than those without VA. Multivariate analysis showed that the cine risk score was significantly associated with VA after adjusting for clinical characteristics, cardiac structure and function including CMR-derived scar extent. These findings indicate that non-contrast, cine CMR inherently contains features to improve VA risk prediction in primary prevention ICD candidates. We solicit participation from multiple centers for external validation.

QRS prolongation in myotonic muscular dystrophy and diffuse fibrosis on cardiac magnetic resonance.

Current noninvasive surrogates of cardiac involvement in myotonic muscular dystrophy have low positive predictive value for sudden death. We hypothesized that the cardiac MR signal-to-noise ratio variance (SNRV) is a surrogate of the spatial heterogeneity of myocardial fibrosis and correlates with electrocardiography changes in myotonic muscular dystrophy. The SNRV for contrast enhanced cardiac MR images was calculated over the entire left ventricle in 43 patients with myotonic muscular dystrophy. All patients underwent standard electrocardiography, and a subset of 23 patients underwent signal averaged electrocardiography. After correcting for body mass index, age, and ejection fraction, SNRV was predictive of QRS duration on standard electrocardiography (1.35-msec increased QRS duration/unit increase in SNRV, P < 0.001). SNRV was also predictive of the low-amplitude late-potential duration (1.49-msec increased low-amplitude late-potential duration/unit increase in SNRV, P < 0.001). Ten-fold cross-validation yielded an area under the receiver operating characteristic curve of 0.87 for the predictive value of SNRV for QRS duration greater than 120 msec. The SNRV of the left ventricle is associated with QRS prolongation, likely due to late depolarization of tissue within islands of patchy fibrosis. The association of SNRV with future clinical events warrants further study.

Clinical decision tool for CRT-P vs. CRT-D implantation: Findings from PROSE-ICD.

BACKGROUND: Cardiac resynchronization therapy (CRT) devices reduce mortality through pacing-induced cardiac resynchronization and implantable cardioverter defibrillator (ICD) therapy for ventricular arrhythmias (VAs). Whether certain factors can predict if patients will benefit more from implantation of CRT pacemakers (CRT-P) or CRT defibrillators (CRT-D) remains unclear. METHODS AND RESULTS: We followed 305 primary prevention CRT-D recipients for the two primary outcomes of HF hospitalization and ICD therapy for VAs. Serum biomarkers, electrocardiographic and clinical variables were collected prior to implant. Multivariable analysis using Cox-proportional hazards model was used to fit the final models. Among 282 patients with follow-up outcome data, 75 (26.6%) were hospitalized for HF and 31 (11%) received appropriate ICD therapy. Independent predictors of HF hospitalization were atrial fibrillation (HR = 1.8 (1.1,2.9)), NYHA class III/IV (HR = 2.2 (1.3,3.6)), ejection fraction <20% (HR = 1.7 (1.1,2.7)), HS-IL6 >4.03pg/ml (HR = 1.7 (1.1,2.9)) and hemoglobin (<12g/dl) (HR = 2.2 (1.3,3.6)). Independent predictors of appropriate therapy included BUN >20mg/dL (HR = 3.0 (1.3,7.1)), HS-CRP >9.42mg/L (HR = 2.3 (1.1,4.7)), no beta blocker therapy (HR = 3.2 (1.4,7.1)) and hematocrit ≥38% (HR = 2.7 (1.03,7.0)). Patients with 0-1 risk factors for appropriate therapy (IR 1 per 100 person-years) and ≥3 risk factors for HF hospitalization (IR 23 per 100-person-years) were more likely to die prior to receiving an appropriate ICD therapy. CONCLUSIONS: Clinical and biomarker data can risk stratify CRT patients for HF progression and VAs. These findings may help characterize subgroups of patients that may benefit more from the use of CRT-P vs. CRT-D systems. TRIAL REGISTRATION: ClinicalTrials.gov NCT00733590.

Sabotage and exploitation in macrophages parasitized by intracellular protozoans.

Macrophages are crucial in immunity to infection. They possess potent antimicrobial function, and efficiently process and present peptide antigens for T-cell activation. Despite this, the intracellular protozoan parasites Toxoplasma gondii, Trypanosoma cruzi and Leishmania spp. target macrophages for infection. Each has adopted unique strategies to subvert macrophage antimicrobial functions. The parasites sabotage killing activities through sophisticated manipulation of intracellular macrophage signaling pathways. These subversive activities are probably dictated by the need to evade microbicidal effector function, as well as to avoid proinflammatory pathology that can destabilize the host-parasite interaction. The molecular details of how intracellular protozoans manipulate macrophage signal transduction pathways for their own ends are beginning to emerge.

Cell wall lipids from Mycobacterium bovis BCG are inflammatory when inoculated within a gel matrix: characterization of a new model of the granulomatous response to mycobacterial components.

The chronic inflammatory response to Mycobacterium generates complex granulomatous lesions that balance containment with destruction of infected tissues. To study the contributing factors from host and pathogen, we developed a model wherein defined mycobacterial components and leukocytes are delivered in a gel, eliciting a localized response that can be retrieved and analysed. We validated the model by comparing responses to the cell wall lipids from Mycobacterium bovis bacillus Calmette-Guerin (BCG) to reported activities in other models. BCG lipid-coated beads and bone marrow-derived macrophages (input macrophages) were injected intraperitoneally into BALB/c mice. Input macrophages and recruited peritoneal exudate cells took up fluorescently tagged BCG lipids, and matrix-associated macrophages and neutrophils produced tumor necrosis factor, interleukin-1alpha, and interleukin-6. Leukocyte numbers and cytokine levels were greater in BCG lipid-bearing matrices than matrices containing non-coated or phosphatidylglycerol-coated beads. Leukocytes arrived in successive waves of neutrophils, macrophages and eosinophils, followed by NK and T cells (CD4(+), CD8(+), or gammadelta) at 7 days and B cells within 12 days. BCG lipids also predisposed matrices for adherence and vascularization, enhancing cellular recruitment. We submit that the matrix model presents pertinent features of the murine granulomatous response that will prove to be an adaptable method for study of this complex response.

Panel 2.16: forensic aspects of disaster fatality management.

This is a summary of the presentations and discussion of Panel 2.16, Forensic Aspects of Disaster Fatality Management of the Conference, Health Aspects of the Tsunami Disaster in Asia, convened by the World Health Organization (WHO) in Phuket, Thailand, 04-06 May 2005. The topics discussed included issues related to forensic aspects that pertain to the responses to the deaths created by the Earthquake and Tsunami. It is presented in the following major sections: (1) overview of victim identification; (2) resource factors in mass-fatality management; (3) mass-fatality management in protecting public health; and (4) reasons to use deoyxribose nucleic acid (DNA) to identify the deceased.

Clinical and serum-based markers are associated with death within 1 year of de novo implant in primary prevention ICD recipients.

BACKGROUND: Implantable cardioverter-defibrillator (ICD) implantation is contraindicated in those with <1-year life expectancy. OBJECTIVES: The aim of this study was to develop a risk prediction score for 1-year mortality in patients with primary prevention ICDs and to determine the incremental improvement in discrimination when serum-based biomarkers are added to traditional clinical variables. METHODS: We analyzed data from the Prospective Observational Study of Implantable Cardioverter-Defibrillators, a large prospective observational study of patients undergoing primary prevention ICD implantation who were extensively phenotyped for clinical and serum-based biomarkers. We identified variables predicting 1-year mortality and synthesized them into a comprehensive risk scoring construct using backward selection. RESULTS: Of 1189 patients deemed by their treating physicians as having a reasonable 1-year life expectancy, 62 (5.2%) patients died within 1 year of ICD implantation. The risk score, composed of 6 clinical factors (age ≥75 years, New York Heart Association class III/IV, atrial fibrillation, estimated glomerular filtration rate <30 mL/min/1.73 m(2), diabetes, and use of diuretics), had good discrimination (area under the curve 0.77) for 1-year mortality. Addition of 3 biomarkers (tumor necrosis factor α receptor II, pro-brain natriuretic peptide, and cardiac troponin T) further improved model discrimination to 0.82. Patients with 0-1, 2-3, 4-6, or 7-9 risk factors had 1-year mortality rates of 0.8%, 2.7%, 16.1%, and 46.2%, respectively. CONCLUSION: Individuals with more comorbidities and elevation of specific serum biomarkers were at increased risk of all-cause mortality despite being deemed as having a reasonable 1-year life expectancy. A simple risk score composed of readily available clinical data and serum biomarkers may better identify patients at high risk of early mortality and improve patient selection and counseling for primary prevention ICD therapy.

Changes in Follow-Up Left Ventricular Ejection Fraction Associated With Outcomes in Primary Prevention Implantable Cardioverter-Defibrillator and Cardiac Resynchronization Therapy Device Recipients.

BACKGROUND: Heart failure patients with primary prevention implantable cardioverter-defibrillators (ICD) may experience an improvement in left ventricular ejection fraction (LVEF) over time. However, it is unclear how LVEF improvement affects subsequent risk for mortality and sudden cardiac death. OBJECTIVES: This study sought to assess changes in LVEF after ICD implantation and the implication of these changes on subsequent mortality and ICD shocks. METHODS: We conducted a prospective cohort study of 538 patients with repeated LVEF assessments after ICD implantation for primary prevention of sudden cardiac death. The primary endpoint was appropriate ICD shock defined as a shock for ventricular tachyarrhythmias. The secondary endpoint was all-cause mortality. RESULTS: Over a mean follow-up of 4.9 years, LVEF decreased in 13.0%, improved in 40.0%, and was unchanged in 47.0% of the patients. In the multivariate Cox models comparing patients with an improved LVEF with those with an unchanged LVEF, the hazard ratios were 0.33 (95% confidence interval: 0.18 to 0.59) for mortality and 0.29 (95% confidence interval: 0.11 to 0.78) for appropriate shock. During follow-up, 25% of patients showed an improvement in LVEF to >35% and their risk of appropriate shock decreased but was not eliminated. CONCLUSIONS: Among primary prevention ICD patients, 40.0% had an improved LVEF during follow-up and 25% had LVEF improved to >35%. Changes in LVEF were inversely associated with all-cause mortality and appropriate shocks for ventricular tachyarrhythmias. In patients whose follow-up LVEF improved to >35%, the risk of an appropriate shock remained but was markedly decreased.

Predictors of mortality, LVAD implant, or heart transplant in primary prevention cardiac resynchronization therapy recipients: The HF-CRT score.

BACKGROUND: Cardiac resynchronization therapy (CRT) reduces morbidity and mortality among individuals with dyssynchronous systolic heart failure (HF). However, patient outcomes vary, with some at higher risk than others for HF progression and death. OBJECTIVE: To develop a risk prediction score incorporating variables associated with mortality, left ventricular assist device (LVAD) implant, or heart transplant in recipients of a primary prevention cardiac resynchronization therapy-defibrillator (CRT-D). METHODS: We followed 305 CRT-D patients from the Prospective Observational Study of Implantable Cardioverter-Defibrillators for the composite outcome of all-cause mortality, LVAD implant, or heart transplant soon after device implantation. Serum biomarkers and electrocardiographic and clinical variables were collected at implant. Multivariable analysis using the Cox proportional hazards model with stepwise selection method was used to fit the final model. RESULTS: Among 305 patients, 53 experienced the composite endpoint. In multivariable analysis, 5 independent predictors ("HF-CRT") were identified: high-sensitivity C-reactive protein >9.42 ng/L (HR = 2.5 [1.4, 4.5]), New York Heart Association functional class III/IV (HR = 2.3 [1.2, 4.5]), creatinine >1.2 mg/dL (HR = 2.7 [1.4, 5.1]), red blood cell count <4.3 × 10(6)/µL (HR = 2.4 [1.3, 4.7]), and cardiac troponin T >28 ng/L (HR = 2.7 [1.4, 5.2]). One point was attributed to each predictor and 3 score categories were identified. Patients with scores 0-1, 2-3, and 4-5 had a 3-year cumulative event-free survival of 96.8%, 79.7%, and 35.2%, respectively (log-rank, P < .001). CONCLUSION: A simple score combining clinical and readily available biomarker data can risk-stratify CRT patients for HF progression and death. These findings may help identify patients who are in need of closer monitoring or early application of more aggressive circulatory support.

A putative serine protease among the excretory-secretory glycoproteins of L1 Trichinella spiralis.

Trichinella spiralis first-stage larvae infect susceptible hosts by invading epithelial cells that line the small intestine. During this process the larva disgorges several glycoproteins that bear an unusual, highly antigenic sugar moiety, tyvelose (3,6-dideoxy arabinohexose). Monoclonal antibodies specific for tyvelose protect the intestine against infection, implicating tyvelose-bearing glycoproteins as mediators of invasion and niche establishment in the intestinal epithelium. In order to investigate these glycoproteins at the molecular level, we first prepared monoclonal anti-peptide antibodies. The antibodies bind a family of glycoproteins that are present in excretory-secretory products of first-stage larvae and are delivered to epithelial cells during invasion by T. spiralis. The major species present in an affinity purified fraction of crude T. spiralis antigens were subjected to tryptic peptide digestion. De novo amino acid sequencing of the peptides using Q-TOF tandem mass spectrometry, in combination with database searches and antibody screening of an L1 cDNA library, showed that the glycoproteins are variably glycosylated homologues of the serine protease family.