Prevalence, Clinical Severity, and Serotype Distribution of Pneumococcal Pneumonia Among Adults Hospitalized With Community-Acquired Pneumonia in Tennessee and Georgia, 2018-2022.

INTRODUCTION: Understanding the pneumococcal serotypes causing community-acquired pneumonia (CAP) is essential for evaluating the impact of pneumococcal vaccines. METHODS: We conducted a prospective surveillance study of adults aged ≥18 years hospitalized with CAP at 3 hospitals in Tennessee and Georgia between 1 September 2018 and 31 October 2022. We assessed for pneumococcal etiology with cultures, the BinaxNOW urinary antigen detection test, and serotype-specific urinary antigen detection assays that detect 30 pneumococcal serotypes contained in the investigational pneumococcal conjugate vaccine V116, as well as licensed vaccines PCV15 and PCV20 (except serotype 15B). The distribution of pneumococcal serotypes was calculated based on serotype-specific urinary antigen detection results. RESULTS: Among 2917 hospitalized adults enrolled with CAP, 352 (12.1%) patients had Streptococcus pneumoniae detected, including 51 (1.7%) patients with invasive pneumococcal pneumonia. The 8 most commonly detected serotypes were: 3, 22F, 19A, 35B, 9N, 19F, 23A, and 11A. Among 2917 adults with CAP, 272 (9.3%) had a serotype detected that is contained in V116, compared to 196 (6.7%) patients with a serotype contained in PCV20 (P < .001), and 168 (5.8%) patients with a serotype contained in PCV15 (P < .001). A serotype contained in V116 but not PCV15 or PCV20 was detected in 120 (4.1%) patients, representing 38.0% of serotype detections. CONCLUSIONS: Approximately 12% of adults hospitalized with CAP had S. pneumoniae detected, and approximately one-third of the detected pneumococcal serotypes were not contained in PCV15 or PCV20. Development of new pneumococcal vaccines with expanded serotype coverage has the potential to prevent a substantial burden of disease.

Human papillomavirus-driven head and neck cancers in Japan during 2008-2009 and 2018-2019: The BROADEN study.

There is limited understanding of epidemiology and time trends of human papilloma virus (HPV)-driven head and neck cancers (HNC) in Japan, especially outside of the oropharynx. To assess HPV-driven HNC, a non-interventional study (BROADEN) of HNC patients diagnosed in 2008-2009 and 2018-2019 was conducted in Japan. Adult patients with oropharyngeal, nasopharyngeal, laryngeal, hypopharyngeal or oral cavity cancers were included in this study. HPV was centrally tested using p16INK4a immunohistochemistry, HPV-DNA PCR and HPV E6*I mRNA. HPV attributability required positivity in at least two tests (p16INK4a immunohistochemistry, HPV-DNA PCR, HPV E6*I mRNA) in the oropharynx, and HPV-DNA and HPV E6*I mRNA positivity for non-oropharynx sites. Nineteen hospitals included a total of 1108 patients, of whom 981 had valid samples. Men accounted for 82% of HNC diagnoses. Patients in the earlier cohort were younger and included a higher percentage of smokers. There was an increasing trend of HPV-driven oropharyngeal cancer over the last decade, from 44.2% to 51.7%. HPV attribution in nasopharyngeal cancers was 3.2% in 2008-2009 and 7.5% in 2018-2019; and 4.4% and 0% for larynx respectively. In total, 95.2% of HPV-driven HNC were attributed to HPV genotypes included in the 9-valent HPV vaccine being HPV16 the most prominent genotype. These results suggest that an epidemiologic shift is happening in Japan, with a decrease in smoking and alcohol use and an increase in HPV-driven HNC. The increasing trend of HPV-driven HNC in Japan highlights the need for preventive strategies to mitigate the rise of HPV-driven HNC.

Strathclyde minor groove binders (S-MGBs) with activity against Acanthamoeba castellanii.

BACKGROUND: Acanthamoeba spp. is the causative agent of Acanthamoeba keratitis and granulomatous amoebic encephalitis. Strathclyde minor groove binders (S-MGBs) are a promising new class of anti-infective agent that have been shown to be effective against many infectious organisms. OBJECTIVES: To synthesize and evaluate the anti-Acanthamoeba activity of a panel of S-MGBs, and therefore determine the potential of this class for further development. METHODS: A panel of 12 S-MGBs was synthesized and anti-Acanthamoeba activity was determined using an alamarBlue™-based trophocidal assay against Acanthamoeba castellanii. Cross-screening against Trypanosoma brucei brucei, Staphylococcus aureus and Escherichia coli was used to investigate selective potency. Cytotoxicity against HEK293 cells allowed for selective toxicity to be measured. DNA binding studies were carried out using native mass spectrometry and DNA thermal shift assays. RESULTS AND DISCUSSION: S-MGB-241 has an IC50 of 6.6 µM against A. castellanii, comparable to the clinically used miltefosine (5.6 µM) and negligible activity against the other organisms. It was also found to have an IC50 > 100 µM against HEK293 cells, demonstrating low cytotoxicity. S-MGB-241 binds to DNA as a dimer, albeit weakly compared to other S-MGBs previously studied. This was confirmed by DNA thermal shift assay with a ΔTm = 1 ±â€Š0.1°C. CONCLUSIONS: Together, these data provide confidence that S-MGBs can be further optimized to generate new, potent treatments for Acanthameoba spp. infections. In particular, S-MGB-241, has been identified as a 'hit' compound that is selectively active against A. castellanii, providing a starting point from which to begin optimization of DNA binding and potency.

Effects of Biological Sex and Pregnancy on SARS-CoV-2 Pathogenesis and Vaccine Outcomes.

SARS-CoV-2 is the causative agent of COVID-19 in humans and has resulted in the death of millions of people worldwide. Similar numbers of infections have been documented in males and females; males, however, are more likely than females to be hospitalized, require intensive care unit, or die from COVID-19. The mechanisms that account for this are multi-factorial and are likely to include differential expression of ACE2 and TMPRSS2 molecules that are required for viral entry into hosts cells and sex differences in the immune response, which are due to modulation of cellular functions by sex hormones and differences in chromosomal gene expression. Furthermore, as comorbidities are also associated with poorer outcomes to SARS-CoV-2 infection and several comorbidities are overrepresented in males, these are also likely to contribute to the observed sex differences. Despite their relative better prognosis following infection with SARS-CoV-2, females do have poorer outcomes during pregnancy. This is likely to be due to pregnancy-induced changes in the immune system that adversely affect viral immunity and disruption of the renin-angiotensin system. Importantly, vaccination reduces the severity of disease in males and females, including pregnant females, and there is no evidence that vaccination has any adverse effects on the outcomes of pregnancy.

Intramedullary nailing of concurrent ipsilateral fractures of the tibia and femur: primary synchronous nailing versus staged osteosynthesis with temporizing external fixation.

INTRODUCTION: The optimal timing to definitive osteosynthesis in the polytraumatized patient remains an unanswered question. Early total care, damage control orthopaedics, and early appropriate care have been described to manage the fractures in these patients, but there is a paucity of literature specific to ipsilateral tibial and femoral fractures. We sought the perioperative outcomes of primary simultaneous intramedullary nailing (IMN) versus temporizing external fixation (EF) of both fractures. METHODS: A chart review of all patients who sustained fractures of the ipsilateral femur and tibia that were definitively treated with (IMN) from January 2010 to December 2020 was performed. Patients who underwent initial EF and those that were primarily treated with IMNs were examined. RESULTS: IMNs and EF were the initial treatment in 23 and 16 patients, respectively. The mean (range) injury severity score (ISS) was 23.3 (33) in the EF group vs. 18.5 (34) in the IMN group, (p = 0.0686). The EF group had a higher total transfused units of packed red blood cells 7.4 vs. 2.8, the mean initial operative time was 236 vs. 282.6 (min), (p = 0.7399), a longer mean total operative time 601.78 vs. 236 (min), and longer mean length of stay 15.6 vs. 11 (days), (p < 0.5). Rates of complications were not significantly different between groups. CONCLUSION: Primary IMN is as safe as provisional EF in the adequately resuscitated patient with ipsilateral femoral and tibial fractures. This implies the fixation of both fractures into a single surgery without increasing perioperative complications, and decreasing total hospital stay in patients with sufficient preoperative resuscitation.

Economic Evaluation of Vaccination Programs: A Guide for Selecting Modeling Approaches.

OBJECTIVES: Illustrate 3 economic evaluation methods whose value measures may be useful to decision makers considering vaccination programs. METHODS: Keyword searches identified example publications of cost-effectiveness analysis (CEA), fiscal health modeling (FHM), and constrained optimization (CO) for economic evaluation of a vaccination program in countries where at least 2 of the methods had been used. We examined the extent to which different value measures may be useful for decision makers considering adoption of a new vaccination program. With these findings, we created a guide for selecting modeling approaches illustrating the decision-maker contexts and policy objectives for which each method may be useful. RESULTS: We identified 8 countries with published evaluations for vaccination programs using >1 method for 4 infections: influenza, human papilloma virus, rotavirus, and malaria. CEA studies targeted health system decision makers using a threshold to determine the efficiency of a new vaccination program. FHM studies targeted public sector spending decision makers estimating lifetime changes in government tax revenue net of transfer payments. CO studies targeted decision makers selecting from a mix of options for preventing an infectious disease within budget and feasibility constraints. Cost and utility inputs, epidemiologic models, comparators, and constraints varied by modeling method. CONCLUSIONS: Although CEAs measures of incremental cost-effectiveness ratios are critical for understanding vaccination program efficiency for all decision makers determining access and reimbursement, FHMs provide measures of the program's impact on public spending for government officials, and COs provide measures of the optimal mix of all prevention interventions for public health officials.

CaMKII Splice Variants in Vascular Smooth Muscle Cells: The Next Step or Redundancy?

Vascular smooth muscle cells (VSMCs) help to maintain the normal physiological contractility of arterial vessels to control blood pressure; they can also contribute to vascular disease such as atherosclerosis. Ca2+/calmodulin-dependent kinase II (CaMKII), a multifunctional enzyme with four isoforms and multiple alternative splice variants, contributes to numerous functions within VSMCs. The role of these isoforms has been widely studied across numerous tissue types; however, their functions are still largely unknown within the vasculature. Even more understudied is the role of the different splice variants of each isoform in such signaling pathways. This review evaluates the role of the different CaMKII splice variants in vascular pathological and physiological mechanisms, aiming to show the need for more research to highlight both the deleterious and protective functions of the various splice variants.

Effect of alterations in whole-body cryotherapy (WBC) exposure on post-match recovery markers in elite Premier League soccer players.

The use of whole-body cryotherapy (WBC) as a recovery intervention is prevalent amongst elite soccer players. However, there is a distinct lack of data available around chronic WBC use and post-match recovery markers in elite soccer. The aim of this study was to investigate the impact of different levels of WBC exposure on subjective and objective measures of post-match recovery in elite soccer players during a chronic exposure period. Sixteen male senior professional outfield soccer players participated in this study over two seasons. K means cluster analysis was used to classify low (-114 ± 2°C for 133 ± 2 s), medium (-121 ± 1°C for 173 ± 2 s) and high (-133 ± 1°C for 181 ± 2 s) cryotherapy exposure indexes (CEI). Salivary markers (immunoglobulin A (IgA) and alpha amylase (AA)) and subjective wellness scores (perceived fatigue, sleep quality, general muscle soreness and stress) were collected post-match across both seasons. Training load (session-RPE) was collected and used as a covariate to control for the load amongst groups. No differences were seen in perceived measures of wellness and salivary AA. Significantly lower IgA concentrations were observed in the medium CEI group (255 ± 32 µg∙ml-1) compared to the low (328 ± 38 µg∙ml-1) and high (306 ± 32 µg∙ml-1) groups. Therefore, increasing the level of chronic WBC exposure appears to have no additional benefit on subjective recovery and alpha amylase response post-match. However, there appears to be an optimal chronic WBC dose with regards to IgA response.

Fresh Extraction of the Proton Charge Radius from Electron Scattering.

We present a novel method for extracting the proton radius from elastic electron-proton (ep) scattering data. The approach is based on interpolation via continued fractions augmented by statistical sampling and avoids any assumptions on the form of function used for the representation of data and subsequent extrapolation onto Q^{2}≃0. Applying the method to extant modern ep datasets, we find that all results are mutually consistent and, combining them, we arrive at r_{p}=0.847(8) fm. This result compares favorably with values obtained from contemporary measurements of the Lamb shift in muonic hydrogen, transitions in electronic hydrogen, and muonic deuterium spectroscopy.

Toxoplasma gondii infection reduces serum progesterone levels and adverse effects at the maternal-foetal interface.

AIMS: Pregnant BALB/c mice infected with a Toxoplasma gondii type II strain were used to determine how pregnancy interferes with the development of maternal immunity to T gondii and how infection disrupts pregnancy and foetal development. METHODS: Maternal and foetal parasite loads were assessed by amplification of T gondii SAG1 using qPCR. Adverse effects of infection were evaluated on foetal-placental development by quantification of implantation units undergoing resorption and by histopathological analyses. Serum progesterone levels were quantified by immunoassay. The effect of T gondii infection on maternal immunity was determined by assessing the cellular composition of spleens by flow cytometry. RESULTS: Infected pregnant mice exhibited clinical signs of infection, inflammation and necrosis at the maternal-foetal interface and decreased serum progesterone levels. In infected mice, there was a clear effect of pregnancy and infection on macrophage cell numbers. However, no differences in the parasite load were detected between non-pregnant and pregnant mice. CONCLUSIONS: Maternal T gondii infection induced adverse effects at the maternal-foetal interface. Alterations were found in immune spleen cells, dependent on the day of pregnancy, relative to nonpregnant animals. The results obtained suggest a pregnancy-dependent mechanism during T gondii infection able to interfere with macrophage numbers.

Time before return to play for the most common injuries in professional football: a 16-year follow-up of the UEFA Elite Club Injury Study.

OBJECTIVES: The objective was to describe the typical duration of absence following the most common injury diagnoses in professional football. METHODS: Injuries were registered by medical staff members of football clubs participating in the Union of European Football Association Elite Club Injury Study. Duration of absence due to an injury was defined by the number of days that passed between the date of the injury occurrence and the date when the medical team allowed the player to return to full participation. In total, 22 942 injuries registered during 494 team-seasons were included in the study. RESULTS: The 31 most common injury diagnoses constituted a total of 78 % of all reported injuries. Most of these injuries were either mild (leading to a median absence of 7 days or less, 6440 cases = 42%) or moderate (median absence: 7-28 days, 56% = 8518 cases) while only few (2% = 311 cases) were severe (median absence of >28 days). The mean duration of absence from training and competition was significantly different (p < 0.05) between index injuries and re-injuries for six diagnoses (Achilles tendon pain, calf muscle injury, groin adductor pain, hamstring muscle injuries and quadriceps muscle injury) with longer absence following re-injuries for all six diagnoses CONCLUSIONS: The majority of all time loss due to injuries in professional football stems from injuries with an individual absence of up to 4 weeks. This article can provide guidelines for expected time away from training and competition for the most common injury types as well as for its realistic range.

The physical demands of professional soccer goalkeepers throughout a week-long competitive microcycle and transiently throughout match-play.

The physical demands of English Premier League soccer goalkeepers were quantified during training and match-play in a two-part study. Goalkeeper-specific micromechanical electrical systems (MEMS) devices, profiled training and match-day activities throughout one competitive week (n=8; part A). Changes in MEMS-derived outputs were also profiled throughout match-play (100 matches; n=8, 18±14 observations per goalkeeper; part B). In part A, goalkeeping-training elicited the most dives (51±11) versus all activities (all p≤0.030) except shooting-training (p=0.069). Small-sided games elicited the fewest (5±3) dives (all p≤0.012). High-speed distance covered in match (103±72 m) was similar to goalkeeping-training (p=0.484), while exceeding shooting-training, small-sided games, pre-match shooting, and pre-match warm-up (all p=0.012). Most changes of direction (34±12) and explosive efforts (70±18) occurred during goalkeeping-training, with values exceeding match (both p=0.012). In part B, between-half reductions in total distance, but increased high-speed changes of direction and explosive efforts, occurred (both p≤0.05). Excluding the number of high jumps, all variables differed from 0-15-min during at least one match epoch, with more dives (1.3±1.4 vs 1.0±1.1) and explosive efforts (2.5±2.4 vs 2.0±1.8) performed between 75-90-min versus 0-15-min (all p<0.05). These data highlight the differing physical demands of various activities performed by professional soccer goalkeepers throughout a competitive week.

How does toxoplasmosis affect the maternal-foetal immune interface and pregnancy?

Toxoplasma gondii is a zoonotic parasite which, depending on the geographical location, can infect between 10% and 90% of humans. Infection during pregnancy may result in congenital toxoplasmosis. The effects on the foetus vary depending on the stage of gestation in which primary maternal infection arises. A large body of research has focused on understanding immune response to toxoplasmosis, although few studies have addressed how it is affected by pregnancy or the pathological consequences of infection at the maternal-foetal interface. There is a lack of knowledge about how maternal immune cells, specifically macrophages, are modulated during infection and the resulting consequences for parasite control and pathology. Herein, we discuss the potential of T. gondii infection to affect the maternal-foetal interface and the potential of pregnancy to disrupt maternal immunity to T. gondii infection.

Acanthamoeba proteases contribute to macrophage activation through PAR1 , but not PAR2.

AIM: Acanthamoeba infections are characterized by an intense localized innate immune response associated with an influx of macrophages. Acanthamoeba protease production is known to affect virulence. Herein, the ability of Acanthamoeba trophozoite proteases, of either the laboratory Neff strain or a recently isolated clinical strain, to stimulate IL-12 and IL-6 and to activate protease-activated receptors, PAR1 and PAR2 expressed on murine macrophages, was investigated. METHOD AND RESULTS: Using selected protease inhibitors, leupeptin and E64, we showed that Acanthamoeba proteases can stimulate IL-12 and IL-6 by murine macrophages. Subsequently, using specific antagonists to inhibit PAR1 , and bone marrow-derived macrophages from PAR2 gene-deficient mice, we demonstrate that PAR1 , but not PAR2 contributes to macrophage IL-12 production in response to Acanthamoeba. In contrast, Acanthamoeba-induced IL-6 production is PAR1 and PAR2 independent. CONCLUSION: This study shows for the first time the involvement of PARs, expressed on macrophages, in the response to Acanthamoeba trophozoites and might provide useful insight into Acanthamoeba infections and their future treatments.

Human Parahippocampal Cortex Supports Spatial Binding in Visual Working Memory.

Studies investigating the functional organization of the medial temporal lobe (MTL) suggest that parahippocampal cortex (PHC) generates representations of spatial and contextual information used by the hippocampus in the formation of episodic memories. However, evidence from animal studies also implicates PHC in spatial binding of visual information held in short term, working memory. Here we examined a 46-year-old man (P.J.), after he had recovered from bilateral medial occipitotemporal cortex strokes resulting in ischemic lesions of PHC and hippocampal atrophy, and a group of age-matched healthy controls. When recalling the color of 1 of 2 objects, P.J. misidentified the target when cued by its location, but not shape. When recalling the position of 1 of 3 objects, he frequently misidentified the target, which was cued by its color. Increasing the duration of the memory delay had no impact on the proportion of binding errors, but did significantly worsen recall precision in both P.J. and controls. We conclude that PHC may play a crucial role in spatial binding during encoding of visual information in working memory.

The use of antibiotics in the treatment of pediatric varicella patients: real-world evidence from the multi-country MARVEL study in Latin America & Europe.

BACKGROUND: Varicella is a highly contagious childhood disease. Generally benign, serious complications necessitating antibiotic use may occur. The objective of this study was to characterize the rate, appropriateness and patterns of real-world antibiotic prescribing for management of varicella-associated complications, prior to universal varicella vaccination (UVV) implementation. METHODS: Pooled, post-hoc analysis of 5 international, multicenter, retrospective chart reviews studies (Argentina, Hungary, Mexico, Peru, Poland). Inpatient and outpatient primary pediatric (1-14 years) varicella cases, diagnosed between 2009 and 2016, were eligible. Outcomes, assessed descriptively, included varicella-associated complications and antibiotic use. Three antibiotic prescribing scenarios were defined based on complication profile in chart: evidence of microbiologically confirmed bacterial infection (Scenario A); insufficient evidence confirming microbiological confirmation (Scenario B); no evidence of microbiological confirmation (Scenario C). Stratification was performed by patient status (inpatient vs. outpatient) and country. RESULTS: Four hundred one outpatients and 386 inpatients were included. Mean (SD) outpatient age was 3.6 (2.8) years; inpatient age was 3.1 (2.8) years. Male gender was predominant. Overall, 12.2% outpatients reported ≥1 infectious complication, 3.7% ≥1 bacterial infection, and 0.5% ≥1 microbiologically confirmed infection; inpatient complication rates were 78.8, 33.2 and 16.6%, respectively. Antibiotics were prescribed to 12.7% of outpatients and 68.9% of inpatients. Among users, ß-lactamases (class), and clindamycin (agent), dominated prescriptions. Scenario A was assigned to 3.9% (outpatients) vs 13.2% (inpatients); Scenario B: 2.0% vs. 6.0%; Scenario C: 94.1% vs. 80.8%. CONCLUSIONS: High rates of infectious complications and antibiotic use are reported, with low rates of microbiological confirmation suggesting possible antibiotic misuse for management of varicella complications.

Skin fiducial markers enable accurate computerized navigation resection of simulated soft tissue tumors: A static cadaveric model pilot study.

BACKGROUND: This static cadaveric model pilot study evaluated the agreement between planned and resected margins of simulated soft tissue tumors (SSTT) using skin fiducial markers for computerized navigation registration. METHODS: Markers were applied before magnetic resonance imaging scans of lower extremities implanted with SSTT. A navigation pointer was used for registration and to guide SSTT resection with approximately 10 mm planned margins. Digital calipers were used to measure resection margins. Kolmogorov-Smirnov tests were used to confirm measurement normality. A one-sample t test was used to determine measurement group differences (P ≤ 0.05). Bland-Altman analysis and histogram plots compared planned and resected margins. RESULTS: Ninety-eight resection margins were measured. The planned margin mean was 10.0 mm (95% confidence interval [CI] = 9.8-10.2 mm) and the resected margin mean was 11.5 mm (95% CI = 11.0-12.1 mm). One-sample t test results identified a 0.75 mm, 95% CI = 0.5-0.99 mm difference (P < 0.001). Good measurement agreement was observed with 94.9% (93/98) of resections occurring within two standard deviations of the mean measurement difference. CONCLUSIONS: Skin fiducial marker use for computerized navigation system registration displayed promising results. With further research, these markers may become an effective, noninvasive method for aiding in soft tissue tumor resection.

Behavioral Economics and Physician Board Meetings: Opportunity Cost, Regret, and Their Mitigation in Orthopaedic Surgery.

Health care is a business. Health care providers must become familiar with terms such as opportunity costs, the potential loss or gain when one choice is made in lieu of another. The purpose of this study was to calculate the opportunity cost of two orthopaedic surgery society board meetings and discuss these in the context of behavioral economics and regret. A literature search was conducted to determine an orthopaedic surgeon's average yearly salary, hours worked per week, and weeks worked per year. The details of two orthopaedic surgery professional society meetings that one senior author (CSR) attended were used to calculate opportunity cost. Although the true benefits are multifactorial and difficult to objectively quantify, awareness of the cost-benefit ratio can help guide time and resource management to maximize the return on investment while minimizing buyer's remorse and perhaps influence the media by which medical meetings are held in the future. (Journal of Surgical Orthopaedic Advances 27(1):10-13, 2018).

Acanthamoeba Activates Macrophages Predominantly through Toll-Like Receptor 4- and MyD88-Dependent Mechanisms To Induce Interleukin-12 (IL-12) and IL-6.

Acanthamoeba castellanii is a ubiquitous free-living amoeba with a worldwide distribution that can occasionally infect humans, causing particularly severe infections in immunocompromised individuals. Dissecting the immunology of Acanthamoeba infections has been considered problematic due to the very low incidence of disease, despite the high exposure rates. While macrophages are acknowledged as playing a significant role in Acanthamoeba infections, little is known about how this facultative parasite influences macrophage activity. Therefore, in this study we investigated the effects of Acanthamoeba on the activation of resting macrophages. Consequently, murine bone marrow-derived macrophages were cocultured with trophozoites of either the laboratory Neff strain or a clinical isolate of A. castellaniiIn vitro real-time imaging demonstrated that trophozoites of both strains often established evanescent contact with macrophages. Both Acanthamoeba strains induced a proinflammatory macrophage phenotype characterized by the significant production of interleukin-12 (IL-12) and IL-6. However, macrophages cocultured with the clinical isolate of Acanthamoeba produced significantly less IL-12 and IL-6 than the Neff strain. The utilization of macrophages derived from MyD88-, TRIF-, Toll-like receptor 2 (TLR2)-, TLR4-, and TLR2/4-deficient mice indicated that Acanthamoeba-induced proinflammatory cytokine production was through MyD88-dependent, TRIF-independent, TLR4-induced events. This study shows for the first time the involvement of TLRs expressed on macrophages in the recognition of and response to Acanthamoeba trophozoites.