Glioblastoma hijacks neuronal mechanisms for brain invasion.

Glioblastomas are incurable tumors infiltrating the brain. A subpopulation of glioblastoma cells forms a functional and therapy-resistant tumor cell network interconnected by tumor microtubes (TMs). Other subpopulations appear unconnected, and their biological role remains unclear. Here, we demonstrate that whole-brain colonization is fueled by glioblastoma cells that lack connections with other tumor cells and astrocytes yet receive synaptic input from neurons. This subpopulation corresponds to neuronal and neural-progenitor-like tumor cell states, as defined by single-cell transcriptomics, both in mouse models and in the human disease. Tumor cell invasion resembled neuronal migration mechanisms and adopted a Lévy-like movement pattern of probing the environment. Neuronal activity induced complex calcium signals in glioblastoma cells followed by the de novo formation of TMs and increased invasion speed. Collectively, superimposing molecular and functional single-cell data revealed that neuronal mechanisms govern glioblastoma cell invasion on multiple levels. This explains how glioblastoma's dissemination and cellular heterogeneity are closely interlinked.

MicroRNA-142 Is Critical for the Homeostasis and Function of Type 1 Innate Lymphoid Cells.

Natural killer (NK) cells are cytotoxic type 1 innate lymphoid cells (ILCs) that defend against viruses and mediate anti-tumor responses, yet mechanisms controlling their development and function remain incompletely understood. We hypothesized that the abundantly expressed microRNA-142 (miR-142) is a critical regulator of type 1 ILC biology. Interleukin-15 (IL-15) signaling induced miR-142 expression, whereas global and ILC-specific miR-142-deficient mice exhibited a cell-intrinsic loss of NK cells. Death of NK cells resulted from diminished IL-15 receptor signaling within miR-142-deficient mice, likely via reduced suppressor of cytokine signaling-1 (Socs1) regulation by miR-142-5p. ILCs persisting in Mir142-/- mice demonstrated increased expression of the miR-142-3p target αV integrin, which supported their survival. Global miR-142-deficient mice exhibited an expansion of ILC1-like cells concurrent with increased transforming growth factor-ß (TGF-ß) signaling. Further, miR-142-deficient mice had reduced NK-cell-dependent function and increased susceptibility to murine cytomegalovirus (MCMV) infection. Thus, miR-142 critically integrates environmental cues for proper type 1 ILC homeostasis and defense against viral infection.

Memory NK Cells Take Out the (Mitochondrial) Garbage.

The molecular mechanisms important to generate innate natural killer cell "memory" are poorly understood. In this issue of Immunity, O'Sullivan et al. (2015) demonstrate that mitophagy plays a critical role in natural killer cell memory formation following viral infection.

Survey on colostrum management by German dairy farmers focusing on frozen colostrum storage.

Because calves are born with low levels of antibodies, effective colostrum management is one of the most critical factors for successful calf rearing. A timely and adequate supply of sufficiently high-quality colostrum immediately after birth is essential to ensure the passive immunization of calves. Frozen colostrum reserves are recommended to fulfill the immunological and nutrient requirements of newborn calves, even in exceptional situations; however, the implementation rates on German dairy farms and challenges of realization remain unclear. A 33-question online survey, focused on frozen colostrum reserves, was developed to obtain an overview of colostrum management practices on German dairy farms. The questionnaire was divided into 3 sections: 1. personal data; 2. farm characteristics; 3. colostrum management. Of the 155 responses we received, 63.9% were from female farmers, and 35.5% were from male farmers. Conventional farming was practiced on 89.0% of farms, and organic farming was practiced on 7.1% of farms. Of the respondents, 89.0% froze colostrum. The main reasons for freezing colostrum were: 1. the dam does not produce enough colostrum; 2. the dam cannot be milked; or 3. in cases where the dam dies during birth. Farmers primarily froze colostrum from cows during their third to fifth lactation. Before freezing, 33.1% of the respondents measured indicators in the colostrum to estimate Ig concentrations, whereas 2.3% determined the colostrum quality after freezing. Reusable and disposable PET deposits (23.1%, 22.3%) and ColostroBags (20.0%) were the primary containers used to freeze colostrum. The main reasons for not freezing colostrum were the high labor intensity and the availability of fresh colostrum from other cows. Thawing methods included buckets (47.7%) and professional water baths (13.8%). The survey identified areas in which improved knowledge transfer could enhance colostrum management. Furthermore, there appeared to be a lack of specific, feasible instructions for employees concerning the practical implementation of colostrum management. Most importantly, the regular determination and documentation of Ig concentrations should be emphasized. The added value of stored colostrum, relative to a greater workload, should also be promoted, particularly on smaller farms.

DNA Methylation Signatures of Functional Somatic Syndromes: Systematic Review.

OBJECTIVE: Functional somatic syndromes (FSS) are highly prevalent across all levels of health care. The fact that they are characterized by medically unexplained symptoms, such as fatigue and pain, raises the important question of their underlying pathophysiology. Psychosocial stress represents a significant factor in the development of FSS and can induce long-term modifications at the epigenetic level. The aim of this review was to systematically review, for the first time, whether individuals with FSS are characterized by specific alterations in DNA methylation. METHODS: MEDLINE and PsycINFO were searched from the first available date to September 2022. The inclusion criteria were as follows: a) adults fulfilling the research diagnostic criteria for chronic fatigue syndrome, fibromyalgia syndrome, and/or irritable bowel syndrome; b) healthy control group; and c) candidate-gene or genome-wide study of DNA methylation. RESULTS: Sixteen studies ( N = 957) were included. In candidate-gene studies, specific sites within NR3C1 were identified, which were hypomethylated in individuals with chronic fatigue syndrome compared with healthy controls. In genome-wide studies in chronic fatigue syndrome, a hypomethylated site located to LY86 and hypermethylated sites within HLA-DQB1 were found. In genome-wide studies in fibromyalgia syndrome, differential methylation in sites related to HDAC4 , TMEM44 , KCNQ1 , SLC17A9 , PRKG1 , ALPK3 , TFAP2A , and LY6G5C was found. CONCLUSIONS: Individuals with chronic fatigue syndrome and fibromyalgia syndrome seem to be characterized by altered DNA methylation of genes regulating cellular signaling and immune functioning. In chronic fatigue syndrome, there is preliminary evidence for these to be implicated in key pathophysiological alterations, such as hypocortisolism and low-grade inflammation, and to contribute to the debilitating symptoms these individuals experience. PREREGISTRATION: PROSPERO identifier: CRD42022364720.

Both radiographical and pathological lymph node statuses are independent predictors for survival following neoadjuvant chemotherapy and radical cystectomy for cT3/4 or cN+ bladder cancer.

INTRODUCTION: Urothelial bladder cancer (UBC) with clinical suspicion of locally advanced growth or pelvic lymphogenic spread has a high risk of progression and death. PATIENTS AND METHODS: Bladder cancer patients with locally advanced (cT3/4) tumor growth or suspected pelvic lymphogenic spread (cN+) were treated with preoperative cisplatin-containing chemotherapy and consolidative cystectomy with pelvic lymphadenectomy. We aimed to identify prognostic factors and describe the patients' oncological outcome. RESULTS: A complete dataset including follow-up data was available for 96 patients. In a univariate analysis, we identified cN stage (cN+ vs cN-, HR 2.7, 95% CI 1.3-6.0), response to chemotherapy (HR 0.2, 95% CI 0.1-0.5), ypT stage (ypT0/is/1 vs ypT2-4, HR 3.1, 95% CI 1.4-6.8), ypN stage (ypN + vs ypN-, HR 7.9, 95% CI 3.7-17.0), resection status (HR 4.4, 95% CI HR 1.5-13.0) as significantly associated with cancer-specific survival. In a multivariate regression analysis, both cN and ypN statuses were validated as independent prognostic factors for cancer-specific survival (cN: HR 2.6, 95% CI 1.1-6.1; ypN: HR 5.5, 95% CI 2.0-15.1). DISCUSSION: Lymph node status was identified as a prognostic marker in a high-risk cohort of UBC patients treated with inductive chemotherapy and cystectomy. Establishing cN status as a prognosticator underlines the necessity to aggressively treat these patients despite reported impreciseness of imaging procedures in UCB. Patients with histologically positive lymph nodes following preoperative chemotherapy have a very poor prognosis, and thus, the need for adjuvant systemic treatment is emphasized. CONCLUSION: Both clinically and pathologically affected lymph nodes convey a poor prognosis in bladder cancer and necessitate aggressive treatment.

Translation Fidelity and Respiration Deficits in CLPP-Deficient Tissues: Mechanistic Insights from Mitochondrial Complexome Profiling.

The mitochondrial matrix peptidase CLPP is crucial during cell stress. Its loss causes Perrault syndrome type 3 (PRLTS3) with infertility, neurodegeneration, and a growth deficit. Its target proteins are disaggregated by CLPX, which also regulates heme biosynthesis via unfolding ALAS enzymes, providing access for pyridoxal-5'-phosphate (PLP). Despite efforts in diverse organisms with multiple techniques, CLPXP substrates remain controversial. Here, avoiding recombinant overexpression, we employed complexomics in mitochondria from three mouse tissues to identify endogenous targets. A CLPP absence caused the accumulation and dispersion of CLPX-VWA8 as AAA+ unfoldases, and of PLPBP. Similar changes and CLPX-VWA8 co-migration were evident for mitoribosomal central protuberance clusters, translation factors like GFM1-HARS2, the RNA granule components LRPPRC-SLIRP, and enzymes OAT-ALDH18A1. Mitochondrially translated proteins in testes showed reductions to <30% for MTCO1-3, the mis-assembly of the complex IV supercomplex, and accumulated metal-binding assembly factors COX15-SFXN4. Indeed, heavy metal levels were increased for iron, molybdenum, cobalt, and manganese. RT-qPCR showed compensatory downregulation only for Clpx mRNA; most accumulated proteins appeared transcriptionally upregulated. Immunoblots validated VWA8, MRPL38, MRPL18, GFM1, and OAT accumulation. Co-immunoprecipitation confirmed CLPX binding to MRPL38, GFM1, and OAT, so excess CLPX and PLP may affect their activity. Our data mechanistically elucidate the mitochondrial translation fidelity deficits which underlie progressive hearing impairment in PRLTS3.

Effects of colostrum feeding on the mRNA abundance of genes related to toll-like receptors, key antimicrobial defense molecules, and tight junctions in the small intestine of neonatal dairy calves.

The objective of the present study was to elucidate the effect of feeding either colostrum or milk-based formula on the mRNA abundance of genes related to pathogen recognition [toll-like receptors (TLR1-10)], antimicrobial defense [ß-defensin 1 (DEFB1) and peptidoglycan recognition protein 1 (PGLYRP1)], and tight junctions (claudin 1 = CLDN1, claudin 4 = CLDN4, and occludin = OCLN) in different sections of the small intestine of neonatal calves at d 4 of life. Holstein dairy calves were fed either colostrum (COL; n = 7) or milk-based formula (FOR; n = 7) with comparable nutrient composition but lower contents of several bioactives in the formula than in the respective colostrum group until d 4 of life. Following euthanasia on d 4 (2 h after feeding), tissue samples from the duodenum, jejunum (proximal, middle, and distal), and ileum were collected. The mRNA abundance of the target genes was quantified by quantitative PCR. The mRNA abundance of TLR1, TLR6, TLR9, and TLR10 were greater in COL than in FOR calves. However, the mRNA abundance of TLR2, TLR3, TLR4, TLR5, and TLR7 did not differ between groups. A group × gut region interaction was observed for the mRNA abundance of TLR8 with greater values in duodenum and proximal jejunum of COL than in FOR calves but in the more distal regions, in mid and distal jejunum, and ileum, this diet effect disappeared or was reversed. We observed greater mRNA abundance of TLR1 in the jejunum (middle and distal) and ileum, TLR2, TLR4, TLR6, and TLR9-10 in the distal jejunum and ileum, and of TLR3 in the distal jejunum, and TLR5, TLR7, and TLR8 in the ileum compared with the other gut regions. The mRNA abundance of PGLYRP1, DEFB1, and OCLN did not differ between groups. The mRNA abundance of CLDN1 was greater, but the CLDN4 mRNA tended to be lower in COL than in FOR calves. The mRNA abundance of PGLYRP1 was lower in the distal jejunum and DEFB1 mRNA in the middle jejunum compared with the other gut regions. The mRNA abundances of OCLN and CLDN4 were greater in the duodenum, and of CLDN1 in the middle and proximal jejunum compared with the other gut regions. Overall, the greater mRNA abundance of 5 different TLR, and CLDN1 in most intestinal sections of the COL calves may suggest that feeding colostrum improves immune responsiveness and epithelial barrier function in neonatal calves.

Implementation of management recommendations in unweaned dairy calves in western Germany and associated challenges.

To improve the welfare of livestock, it is important to assess management practices on farms and to identify areas where current scientific recommendations are rarely implemented. Differences in the implementation of recommendations might be explained by the individual farm as well as the characteristics of survey respondents and their attitude toward animal welfare. Hence, the aim of this study was to assess dairy calf management practices, compare them with current scientific recommendations, and to explore factors that influence implementation of the recommended management practices. A 1.5-h interview was performed with stockpersons on 42 dairy farms (mean herd size ± SD = 149.9 ± 16.6 cows) distributed across western Germany in 2018 to 2019. We observed that the management of unweaned calves varied greatly from farm to farm in aspects such as milk-feeding protocols; timing of grouping and disbudding; and access to water, roughage, and concentrate. Major deviations from management recommendations were (1) cleaning calving pen only by removal of bedding without a following disinfection before restocking on 23.8% farms, cleaning of teat buckets without detergents and disinfection (23.8 and 11.9% of farms, respectively), and failure to disinfect navels (29.3% of farms); (2) separating calf and dam after only 5 to 8 h postpartum for calving at night in 97.6% farms and unchecked colostrum quality by 23.8% of survey respondents; (3) feeding waste milk by 72.4% of the farms surveyed; and (4) removing supernumerary teats and disbudding without local anesthesia (90 and 80% farms surveyed, respectively). The number of implemented recommendations on the farms surveyed correlated with who was responsible for calf rearing, and whether prioritizing animal welfare was considered important by the respondents. This study indicated that limitations of individual housing systems, time management, the stockperson's knowledge, and the stockperson's ability to relate to animals posed challenges in implementation of the recommendations. Further research on challenges in calf management and how to overcome them would be helpful to improve calves' welfare in current husbandry systems.

Survey on storage, application and incorporation practices for organic fertilizers in Germany.

Organic fertilizers from animal production might contain undesirable components, such as veterinary medical product (VMP) residues, that are released into the environment during application. In addition to measures to reduce the use of VMPs through animal health measures, manure management could be an expedient strategy to prevent VMPs from entering the environment. The quantity applied is mainly determined by the nitrogen content. In addition, the depth of incorporation into the soil plays a major role in the environmental risk assessment of VMPs. The new regulations of the German fertilizer ordinance (DüV, 2020), which came into force at the beginning of 2020, as well as the changes that have not yet been fully implemented, will result in adjustments to the storage, application and incorporation practices for organic fertilizer. The aim of this study was to gain more information about the practice of storage, application and incorporation and the challenges for farmers in Germany. An online survey among farmers was conducted to determine the status quo. Almost all of the 125 participants kept livestock, predominantly cattle (68%) and pigs (33%). A third of participants (30%) needed a temporary storage site, for example at neighboring farms. Of the participants, 81% (n = 125) owned cropland and/or grassland. On cropland, manure was mostly incorporated at a depth of 3-15 cm, whereas on grassland, it was mostly applied superficially. On grassland lower-emission application techniques such as slot drill or injector procedures have so far rarely been used. The survey results provided important insights about storage, application and incorporation practices for organic fertilizers in Germany which could be used for the calculation of predicted environmental concentrations (PEC) as part of the environmental risk assessments of veterinary pharmaceuticals.

Leucine Supplementation Does Not Restore Diminished Skeletal Muscle Satellite Cell Abundance and Myonuclear Accretion When Protein Intake Is Limiting in Neonatal Pigs.

BACKGROUND: Rapid growth of skeletal muscle in the neonate requires the coordination of protein deposition and myonuclear accretion. During this developmental stage, muscle protein synthesis is highly sensitive to amino acid supply, especially Leu, but we do not know if this is true for satellite cells, the source of muscle fiber myonuclei. OBJECTIVE: We examined whether dietary protein restriction reduces myonuclear accretion in the neonatal pig, and if any reduction in myonuclear accretion is mitigated by restoring Leu intake. METHODS: Neonatal pigs (1.53 ± 0.2 kg) were fitted with jugular vein and gastric catheters and fed 1 of 3 isoenergetic milk replacers every 4 h for 21 d: high protein [HP; 22.5 g protein/(kg/d); n= 8]; restricted protein [RP; 11.2 g protein/(kg/d); n= 10]; or restricted protein with Leu [RPL; 12.0 g protein/(kg/d); n= 10]. Pigs were administered 5-bromo-2'-deoxyuridine (BrdU; 15 mg/kg) intravenously every 12 h from days 6 to 8. Blood was sampled on days 6 and 21 to measure plasma Leu concentrations. On day 21, pigs were killed and the longissimus dorsi (LD) muscle was collected to measure cell morphometry, satellite cell abundance, myonuclear accretion, and insulin-like growth factor (IGF) system expression. RESULTS: Compared with HP pigs, postprandial plasma Leu concentration in RP pigs was 37% and 47% lower on days 6 and 21, respectively (P < 0.05); Leu supplementation in RPL pigs restored postprandial Leu to HP concentrations. Dietary protein restriction reduced LD myofiber cross-sectional area by 21%, satellite cell abundance by 35%, and BrdU+ myonuclear abundance by 25% (P < 0.05); Leu did not reverse these outcomes. Dietary protein restriction reduced LD muscle IGF2 expression by 60%, but not IGF1 or IGF1R expression (P < 0.05); Leu did not rescue IGF2 expression. CONCLUSIONS: Satellite cell abundance and myonuclear accretion in neonatal pigs are compromised when dietary protein intake is restricted and are not restored with Leu supplementation.

Short communication: Colostrum versus formula: Effects on mRNA expression of genes related to branched-chain amino acid metabolism in neonatal dairy calves.

The objective of the current study was to elucidate the effect of feeding colostrum or milk-based formula on the tissue mRNA abundance of the most relevant branched-chain amino acids (BCAA) transporters and catabolizing enzymes in newborn calves. German Holstein calves were fed either colostrum (COL; n = 7) or milk-based formula (FOR; n = 7) with comparable nutrient composition but lower contents of free BCAA, insulin, and insulin-like growth factor-I in the formula than in the respective colostrum for up to 4 d of life. Tissue samples from liver, kidney fat, 3 different muscles [M. longissimus dorsi (MLD), M. semitendinosus (MST), and M. masseter (MM)], as well as duodenum, jejunum, and ileum were collected following euthanasia on d 4 at 2 h after feeding. The plasma-free BCAA were analyzed, and the tissue abundance of solute carrier family 1 member 5 (SLC1A5), SLC7A5, and SLC38A2 as well as mitochondrial isoform of branched-chain aminotransferase (BCATm), branched-chain α-keto acid dehydrogenase E1α (BCKDHA), and branched-chain α-keto acid dehydrogenase E1ß (BCKDHB) were assessed. The preprandial plasma concentrations of free BCAA were affected by time but did not differ between groups. The plasma concentrations of free BCAA decreased in COL, whereas they increased in FOR after feeding, resulting in higher postprandial plasma total BCAA concentrations in FOR than in COL. The mRNA abundances of BCATm, BCKDHA, BCKDHB, as well as BCAA transporters in the liver, were not affected by the diet. In kidney fat, the mRNA abundance of BCAA catabolizing enzymes did not differ between groups, but that of SLC1A5 was lower in FOR than in COL. The mRNA abundance of BCAA catabolizing enzymes in different sections of the small intestine was not affected by the diet, whereas that of SLC7A5 was or tended to be lower in the duodenum, proximal jejunum, and mid jejunum of the COL calves compared with the FOR calves. The mRNA abundance of BCKDHA was lower in MLD and MM but greater in MS for the FOR calves compared with the COL calves. The mRNA abundance of SLC7A5 in MST was lower in FOR than in COL, whereas it was unaffected by the diet in MLD and MM. The differential effect of feeding colostrum on the mRNA abundance of BCKDHA in 3 different muscle tissues might point to a muscle type-specific response. The results also indicate that the colostral BCAA might be favorably used for anabolic metabolism in the small intestine of neonatal calves. Such effects are speculated to be due to the stimulatory effects of growth factors and hormones present in colostrum.

Feasibility Study on the Use of Infrared Thermography to Classify Fattening Pigs into Feeding Groups According Their Body Composition.

Fattening pig husbandry and associated negative environmental impacts due to nitrogen inputs by ammonia emissions are current issues of social discussion. New resource-efficient feeding systems offer great potential to reduce excess nutrient inputs into the environment. Using ultrasound measurements, fattening pigs can be divided into performance groups based on their backfat/muscle ratio to feed them according to their nutritional needs. Ultrasound measurements are not suitable for practical use, so alternatives have to be found. As a non-invasive, contactless method, infrared thermography offers many advantages. This study investigated whether infrared thermography can be used to differentiate between "fat" and "lean" animals. Two evaluation methods with different measurement spot sizes were compared. During a fattening period, 980 pigs were examined three times with an infrared camera. Both methods showed significant differences. Body surface temperature was influenced by factors like measurement spot size and soiling of the animals. Body surface temperature decreased (-5.5 °C), while backfat thickness increased (+0.7 cm) in the course of the fattening period. Significant correlations (R > |0.5|; p < 0.001) between both parameters were found. Differentiation between "fat" and "lean" animals, based on temperature data, was not possible. Nevertheless, the application of thermography should be investigated further with the aim of resource-efficient feeding. The results of this feasibility study can serve as a basis for this.

Human Adaptive Natural Killer Cells: Beyond NKG2C.

Paradigm-shifting studies have identified NKG2C(+) adaptive natural killer (NK) cells in individuals infected with cytomegalovirus. Recently in Cell Reports, Liu et al. demonstrate that NKG2C(-/-) HCMV(+) individuals also generate adaptive NK cells, and reveal CD2 as a major co-stimulatory receptor for these NK cells specialized to respond via FcγRIIIa/CD16.

Small-molecule factor D inhibitors targeting the alternative complement pathway.

Complement is a key component of the innate immune system, recognizing pathogens and promoting their elimination. Complement component 3 (C3) is the central component of the system. Activation of C3 can be initiated by three distinct routes-the classical, the lectin and the alternative pathways-with the alternative pathway also acting as an amplification loop for the other two pathways. The protease factor D (FD) is essential for this amplification process, which, when dysregulated, predisposes individuals to diverse disorders including age-related macular degeneration and paroxysmal nocturnal hemoglobinuria (PNH). Here we describe the identification of potent and selective small-molecule inhibitors of FD. These inhibitors efficiently block alternative pathway (AP) activation and prevent both C3 deposition onto, and lysis of, PNH erythrocytes. Their oral administration inhibited lipopolysaccharide-induced AP activation in FD-humanized mice. These data demonstrate the feasibility of inhibiting the AP with small-molecule antagonists and support the development of FD inhibitors for the treatment of complement-mediated diseases.

Mid-term development of hamstring tendon length and velocity after distal femoral extension osteotomy in children with bilateral cerebral palsy: a retrospective cohort study.

AIM: Flexed knee gait can be treated with distal femoral extension osteotomy (DFEO) and additional patellar tendon advancement (PTA) in children with cerebral palsy (CP). This study assesses changes in hamstring muscle tendon length (MTL) and velocity after DFEO (+PTA). METHOD: Nineteen children (mean age 13y [standard deviation 3y] at surgery) with CP and flexed knee gait who were treated with DFEO (15 limbs) or DFEO+PTA (10 limbs) were retrospectively included in this study. Gait analyses were performed preoperatively (E0), 1 year postoperatively (E1), and for 10 limbs additionally 2 to 5 years postoperatively (E2). Hamstring MTL and velocities were assessed at all examination dates using OpenSim. RESULTS: Hamstring MTL and velocity did not change significantly over time. From E0 to E1, knee flexion in stance improved for both DFEO and DFEO+PTA (p<0.05), knee flexion in swing only improved after DFEO+PTA (p<0.05). The improved knee flexion in stance and swing was maintained at E2. INTERPRETATION: DFEO led to a significant improvement in knee kinematics at E1 which was maintained at E2. DFEO seems to prevent recurrent hamstring tightness but does not lead to lengthened or fastened hamstrings. WHAT THIS PAPER ADDS: Distal femoral extension osteotomy (DFEO) does not change hamstring muscle tendon length. DFEO does not change hamstring lengthening velocity. DFEO leads to a significant improvement in knee kinematics. Changes in knee kinematics after DFEO can be maintained at mid-term. DFEO seems to prevent recurrent hamstring tightness.

PTEN regulates natural killer cell trafficking in vivo.

Phosphatase and tensin homolog (PTEN) is a critical negative regulator of the phosphoinositide-3 kinase pathway, members of which play integral roles in natural killer (NK) cell development and function. However, the functions of PTEN in NK cell biology remain unknown. Here, we used an NK cell-specific PTEN-deletion mouse model to define the ramifications of intrinsic NK cell PTEN loss in vivo. In these mice, there was a significant defect in NK cell numbers in the bone marrow and peripheral organs despite increased proliferation and intact peripheral NK cell maturation. Unexpectedly, we observed a significant expansion of peripheral blood NK cells and the premature egress of NK cells from the bone marrow. The altered trafficking of NK cells from peripheral organs into the blood was due to selective hyperresponsiveness to the blood localizing chemokine S1P. To address the importance of this trafficking defect to NK cell immune responses, we investigated the ability of PTEN-deficient NK cells to traffic to a site of tumor challenge. PTEN-deficient NK cells were defective at migrating to distal tumor sites but were more effective at clearing tumors actively introduced into the peripheral blood. Collectively, these data identify PTEN as an essential regulator of NK cell localization in vivo during both homeostasis and malignancy.

Learning to Fly.

In this narrative medicine essay, an infectious diseases fellow understands while grieving her father that care cannot always be measured in cure but rather in listening and loving.

A comparison of volume clamp method-based continuous noninvasive cardiac output (CNCO) measurement versus intermittent pulmonary artery thermodilution in postoperative cardiothoracic surgery patients.

The CNAP technology (CNSystems Medizintechnik AG, Graz, Austria) allows continuous noninvasive arterial pressure waveform recording based on the volume clamp method and estimation of cardiac output (CO) by pulse contour analysis. We compared CNAP-derived CO measurements (CNCO) with intermittent invasive CO measurements (pulmonary artery catheter; PAC-CO) in postoperative cardiothoracic surgery patients. In 51 intensive care unit patients after cardiothoracic surgery, we measured PAC-CO (criterion standard) and CNCO at three different time points. We conducted two separate comparative analyses: (1) CNCO auto-calibrated to biometric patient data (CNCObio) versus PAC-CO and (2) CNCO calibrated to the first simultaneously measured PAC-CO value (CNCOcal) versus PAC-CO. The agreement between the two methods was statistically assessed by Bland-Altman analysis and the percentage error. In a subgroup of patients, a passive leg raising maneuver was performed for clinical indications and we present the changes in PAC-CO and CNCO in four-quadrant plots (exclusion zone 0.5 L/min) in order to evaluate the trending ability of CNCO. The mean difference between CNCObio and PAC-CO was +0.5 L/min (standard deviation ± 1.3 L/min; 95% limits of agreement -1.9 to +3.0 L/min). The percentage error was 49%. The concordance rate was 100%. For CNCOcal, the mean difference was -0.3 L/min (±0.5 L/min; -1.2 to +0.7 L/min) with a percentage error of 19%. In this clinical study in cardiothoracic surgery patients, CNCOcal showed good agreement when compared with PAC-CO. For CNCObio, we observed a higher percentage error and good trending ability (concordance rate 100%).

Cytokine-Induced Memory-Like Differentiation Enhances Unlicensed Natural Killer Cell Antileukemia and FcγRIIIa-Triggered Responses.

Cytokine-induced memory-like natural killer (NK) cells differentiate after short-term preactivation with IL-12, IL-15, and IL-18 and display enhanced effector function in response to cytokines or tumor targets for weeks after the initial preactivation. Conventional NK cell function depends on a licensing signal, classically delivered by an inhibitory receptor engaging its cognate MHC class I ligand. How licensing status integrates with cytokine-induced memory-like NK cell responses is unknown. We investigated this interaction using killer cell immunoglobulin-like receptor- and HLA-genotyped primary human NK cells. Memory-like differentiation resulted in enhanced IFN-γ production triggered by leukemia targets or FcγRIIIa ligation within licensed NK cells, which exhibited the highest functionality of the NK cell subsets interrogated. IFN-γ production by unlicensed memory-like NK cells was also enhanced to a level comparable with that of licensed control NK cells. Mechanistically, differences in responses to FcγRIIIa-based triggering were not explained by alterations in key signaling intermediates, indicating that the underlying biology of memory-like NK cells is distinct from that of adaptive NK cells in human cytomegalovirus-positive individuals. Additionally, memory-like NK cells responded robustly to cytokine receptor restimulation with no impact of licensing status. These results demonstrate that both licensed and unlicensed memory-like NK cell populations have enhanced functionality, which may be translated to improve leukemia immunotherapy.