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Results for “Growth Differentiation Factor 15”

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At least 19 recordsLinked to original sources

PubMed2026

Long-term follow-up of a phase 1/2 trial of anti-GDF-15 antibody visugromab plus anti-PD-1 antibody nivolumab in anti-PD-1/-L1 relapsed/refractory solid tumors.

BACKGROUND: Resistance to anti-PD-1/PD-L1 therapy is a major unmet need. Growth Differentiation Factor 15 (GDF-15) has been identified as a key resistance factor for anti-PD-1/PD-L1 immunotherapy. Visugromab, a neutralizing anti-GDF-15 antibody, plus the anti-PD-1 antibody nivolumab (V+N) was evaluated in the first-in-human phase 1/2a GDFATHER-01 trial in heavily pretreated participants with locally advanced/metastatic non-squamous non-small-cell lung cancer (nsq NSCLC), urothelial carcinoma (UC), or hepatocellular carcinoma (HCC), stringently defined as anti-PD-1/PD-L1-relapsed/refractory, and showed encouraging objective responses. This analysis reports long-term follow-up of these three phase 2 expansion cohorts of the GDFATHER-01 trial. METHODS: Seventy-seven participants with nsq NSCLC (N=22), UC (N=27), and HCC (N=28) received visugromab (10 mg/kg) plus nivolumab (240 mg) every two weeks until disease progression or unacceptable toxicity. RESULTS: Objective response rates (RECIST v1.1) were 18.2% for nsq NSCLC (4/22; 95%CI 5.2-40.3), 18.5% for UC (5/27; 95%CI 6.3-38.1), and 14.3% for HCC (4/28; 95%CI 4.0-32.7). Median duration of response (DoR) was 32.2 months (95%CI 5.5-38.0), 28.8 months (95%CI 7.4-39.4), and 19.4 months (95%CI 5.8-39.7; with protracted recruitment), respectively, with 7/13 responses (53.8%) ongoing. Confirmed complete response or complete metabolic response (CR or CMR) among responders was 61.5% (8/13), with 7/8 ongoing. In addition, 46.2% (6/13) of responders achieved a deeper response on V+N per RECIST v1.1 than with the prior anti-PD-(L)1 therapy; median DoR on V+N was 28.8 months (95%CI 7.4-38.0) versus 12.0 months (95%CI 8.0-24.0) on initial anti-PD-1/PD-L1 treatment. V+N was generally well tolerated. CONCLUSIONS: In heavily pretreated, advanced/metastatic participants with nsq NSCLC, UC, or HCC who were anti-PD-1/PD-L1-relapsed/refractory, V+N achieved deep and durable objective responses. The observed DoR, depth of response, and CR+CMR rate among responders exceeded those reported for their initial anti-PD-1/PD-L1 therapy. These findings suggest that GDF-15 blockade with visugromab can overcome resistance and enhance the magnitude and durability of anti-PD-1/PD-L1 responses, and warrant further exploration in randomized trials. REGISTRY: ClinicalTrials.gov, TRN: NCT04725474, Registration date: 25 January 2021; EudraCT, TRN: 2020-002103-19, Registration date 16 Dec 2020.

Humans↗

PubMed2026

Large-Scale Plasma Proteomics Reveals Preclinical Biomarkers of Incident Severe Liver Disease.

The absence of robust biomarkers for early detection of severe liver disease (SLD) highlights the critical need for high-throughput proteomics-driven discovery. In this prospective cohort study, we aimed to identify plasma protein signatures associated with incident SLD and assess their clinical utility. Using the large-scale Olink Explore 1536 platform, we quantified 1461 plasma proteins in 46951 participants from the UK Biobank community-based cohort without baseline liver disease. Over a median follow-up of 14.1 years, we identified 490 proteins significantly associated with incident SLD risk. Growth differentiation factor 15 (GDF15) emerged as the strongest predictor, achieving a C-index of 0.80 and outperforming conventional clinical indices (LiverRisk score: 0.75; FIB-4: 0.68; APRI: 0.68). Temporal trajectories revealed that GDF15 levels began increasing up to 10 years before diagnosis, with progressive elevation as the diagnosis timepoint approached. Mendelian randomization analysis supported genetic associations linking higher protein levels of GDF15, FABP1, SPON2, CHI3L1, and PIGR with SLD risk. Our large-scale proteome-wide study not only reveals significant proteomic changes preceding SLD diagnosis but also establishes GDF15 as both a promising preclinical biomarker, opening new avenues for early intervention in at-risk individuals.

Humans↗

PubMed2026

Machine Learning-Driven Prediction of Coronary Artery Disease Risk Based on UK Biobank Plasma Proteomics.

BACKGROUND: Coronary artery disease (CAD) is a leading global cause of mortality, yet the predictive accuracy of conventional risk models is limited. Here, we integrate conventional risk factors, polygenic risk scores, and large-scale proteomics to develop a unified model for enhanced CAD risk prediction. METHODS: Using data from UK Biobank, participants with plasma proteomics and genetic risk data were included after excluding prevalent CAD. Participants from England were split into training (n=32 330) and internal validation (n=13 857) sets, and Scotland/Wales participants formed an external validation set (n=5775). Incident CAD was ascertained from linked health records. A 202-protein proteomic risk score was derived by least absolute shrinkage and selection operator Cox regression, and CatBoost models were trained using conventional risk factors alone and with incremental addition of polygenic risk scores and protein proteomic risk scores; Shapley Additive Explanations-guided forward selection identified a compact protein panel. RESULTS: Across cohorts, the median age was 58 years and ∼45% were men. Protein proteomic risk score was dose-dependently associated with CAD risk. Compared with conventional risk factors alone, integrating polygenic risk scores and protein proteomic risk scores improved discrimination, with the area under the curve increasing from 0.750 (95% CI, 0.732-0.767) to 0.789 (95% CI, 0.772-0.805) in internal validation and from 0.717 (95% CI, 0.683-0.750) to 0.762 (95% CI, 0.732-0.791) in external validation. A 9-protein panel (GDF15 [growth differentiation factor 15], MMP12 [matrix metalloproteinase 12], NPPB [natriuretic peptide B], PGF [placental growth factor], REN [renin], ADGRG2 [adhesion G-protein coupled receptor], ACE2 [angiotensin-converting enzyme 2], CDCP1 [CUB domain-containing protein 1], CXCL17 [C-X-C motif chemokine ligand 17)]) captured most proteomic predictive information. CONCLUSIONS: Our findings demonstrate that integrating conventional risk factors, polygenic risk scores, and proteomic data improves CAD risk prediction. This study highlights the utility of proteomics in precision cardiovascular medicine and simplified risk stratification tools.

Humans↗

PubMed2025

Recognizing the evolution of clinical syndrome spectrum progression in individuals with single large-scale mitochondrial DNA deletion syndromes (SLSMDS).

PURPOSE: Single large-scale mtDNA deletions (SLSMD) result in single large-scale deletion syndromes (SLSMDS). SLSMDS presentations have classically been recognized to encompass at least 3 distinct clinical phenotypes: Pearson syndrome (PS), Kearns-Sayre syndrome (KSS), and chronic progressive ophthalmoplegia. METHODS: A facilitated review of electronic medical records, manual charts, and Research Electronic Data Capture research databases was performed to complete a retrospective natural history study of 30 participants with SLSMDS in a single health system between 2002 and 2020. The evaluated characteristics included genetic and clinical laboratory test values, growth parameters, signs and symptoms, demographics, and patient-reported outcome measures of fatigue, quality of life, and overall function. RESULTS: Detailed cohort characterization highlighted that a recurrent deleted region involving MT-ND5 (HGNC:7641) occurs in 96% of participants with SLSMDS regardless of the clinical phenotype, which tends to evolve over time. Higher blood heteroplasmy correlated with an earlier age of onset. Growth differentiation factor 15 levels were elevated in all participants with SLSMDS. A history of PS was associated with poor survival prognosis. Furthermore, increased fatigue and decreased quality of life have been reported in patients with SLSMD with advanced age. CONCLUSION: A retrospective natural history study of patients with SLSMDS demonstrated the evolution of classically considered PS, Kearns-Sayre syndrome, and chronic progressive ophthalmoplegia clinical presentations in affected individuals, which may inform future clinical trial developments.

Humans↗

PubMed2026

Precision Medicine in Transfusion-Dependent and Non-Transfusion-Dependent β-Thalassemia: Toward Personalized Diagnosis and Therapy.

β-thalassemia comprises a clinically heterogeneous group of disorders in which anemia severity, transfusion exposure, iron loading, and organ complications vary widely among individuals. This structured narrative review summarizes practical applications of precision medicine in transfusion-dependent thalassemia (TDT) and non-transfusion-dependent thalassemia (NTDT), with explicit attention to which strategies apply to each clinical category. Literature indexed in PubMed and Scopus from 2000 to 2025 was reviewed using terms related to thalassemia, precision medicine, magnetic resonance imaging (MRI), chelation tailoring, next-generation sequencing (NGS), fetal hemoglobin (HbF) modifiers, luspatercept, mitapivat, hepcidin, gene therapy, gene editing, and artificial intelligence (AI). Evidence was synthesized descriptively because interventions, outcomes, and populations were heterogeneous, and no pooled meta-analysis was performed. In TDT, precision care is centered on individualized transfusion planning, extended red-cell antigen matching, MRI-guided cardiac and hepatic iron monitoring, organ-directed chelation intensification, and selection of disease-modifying or curative approaches. In NTDT, precision care emphasizes accurate phenotype classification, MRI liver iron concentration, because serum ferritin may underestimate iron burden, selective chelation, surveillance for NTDT-specific complications, and individualized use of agents that improve anemia. Personalized chelation should include deferiprone, either alone or in combination, when cardiac iron is increased. Comprehensive molecular diagnosis should include HBB together with HBA1 and HBA2 assessment, while secondary and tertiary modifiers help explain phenotypic variability and complication risk. Hepcidin and growth differentiation factor 15 (GDF-15) are discussed as investigational biomarkers; transferrin saturation is not recommended for routine iron-overload assessment in thalassemia. AI currently has its strongest role in screening and diagnosis, whereas risk-stratification models remain exploratory. Equitable implementation requires standardized TDT/NTDT pathways, regional MRI and genomics access, longitudinal registries, and multidisciplinary interpretation.

Humans↗

PubMed2026

Proteomic Profiling Captures Residual Cardiovascular Risk Beyond the PREVENT Model in Individuals With Cardiovascular-Kidney-Metabolic Syndrome Stages 2-3.

BACKGROUND: Cardiovascular-kidney-metabolic (CKM) syndrome reflects complex pathobiological interactions among metabolic disorders, kidney injury, and cardiovascular disease (CVD). Stages 2 and 3 represent critical phases of disease progression characterised by high pathological heterogeneity. This study aimed to develop a CVD protein risk score (PRS) for this population and evaluate its incremental predictive value over the PREVENT model. METHODS: This study included 24 017 participants with CKM Stages 2-3 from the UK Biobank. Using 2923 plasma proteins measured via the Olink platform, a PRS was developed in a training set (n = 19 218) using the LASSO method. In the validation set (n = 4799), the incremental predictive performance of this score over the PREVENT model was assessed using Harrell's C-statistic, net reclassification improvement (NRI) and integrated discrimination improvement (IDI). RESULTS: A risk score comprising 63 proteins was constructed, primarily reflecting inflammation, kidney injury and matrix remodelling. Key proteins included growth differentiation factor 15 (GDF15), hepatitis A virus cellular receptor 1 (HAVCR1), matrix metallopeptidase 12 (MMP12) and NT-proBNP. In the validation set, after adjusting for PREVENT risk factors, individuals in the high PRS group had a 2.56-fold higher risk of CVD compared to those in the low score group (HR: 2.56, 95% CI: 1.96-3.37). Integrating the score into the PREVENT model improved the C-statistic by 0.034 (0.672-0.706) and achieved a 10-year NRI of 15.8% (95% CI: 9.5%-20.9%) and an IDI of 2.2% (95% CI: 1.3%-3.3%). CONCLUSION: Combining the PREVENT model with the PRS developed in this study enhances the prediction of future CVD events in the CKM Stages 2-3 population. This approach facilitates the capture of residual risk and supports precision risk stratification and management for this high-risk group.

Humans↗

PubMed2026

Proteomic Profiling of Pulmonary Function and Cardiovascular Disease Risk in the Atherosclerosis Risk in Communities Study.

BACKGROUND: Pulmonary function is linked to cardiovascular disease risk; however, the underlying mechanisms remain unclear. We aimed to identify protein biomarkers associated with pulmonary function and examine their impact on incident chronic obstructive pulmonary disease, coronary heart disease, heart failure, and all-cause mortality. METHODS: Data from White and Black Americans in the Atherosclerosis Risk in Communities study (visit 2: N=11 354, mean age=57 years; visit 5: N=3517, mean age=75 years), a prospective cohort, were analyzed. Linear regression assessed associations between protein levels and pulmonary function measures, including forced expiratory volume in 1 second and forced vital capacity. The impact of the identified proteins on incident chronic obstructive pulmonary disease, coronary heart disease, heart failure, and mortality was estimated using logistic regression and Cox proportional hazards models. Pathway enrichment and Mendelian randomization explored underlying biological functions and causal effects. RESULTS: Of 4766 proteins analyzed, 364 were cross-sectionally associated with forced expiratory volume in 1 second (and forced vital capacity (false discovery rate<0.05). Ninety-four and 270 proteins had concordant positive and negative effects, respectively. Five pathways related to pulmonary and cardiac function were enriched. Of the 364 proteins, 112 were linked to all 4 outcomes, where 86 were associated with increased risk (odds ratio/hazard ratio [OR/HR], 1.05-1.42) and 26 with reduced risk (OR/HR, 0.69-0.96). Six proteins (STAT3 [signal transducer and activator of transcription 3], MIC-1 [growth differentiation factor 15], apoA-II [apolipoprotein A-II], TPST1 [protein-tyrosine sulfotransferase 1], integrin a1b1 [integrin alpha-I: beta-1 complex], and BLC [C-X-C motif chemokine 13]) showed potential inverse causal effects on with forced expiratory volume in 1 second and forced vital capacity, and integrin a1b1 demonstrated consistent inverse associations with chronic obstructive pulmonary disease, coronary heart disease, and heart failure risks. CONCLUSIONS: Proteins associated with pulmonary function may influence CVD risk. Six proteins, including integrin a1b1, represent promising targets for future interventions.

Aged↗

PubMed2026

Enhanced Prediction of Peripheral Artery Disease Using Plasma Proteomics Among Individuals Without Diabetes.

BACKGROUND: Although peripheral artery disease (PAD) is an important diabetes complication, a substantial proportion of cases occur among individuals without diabetes. This study aimed to assess the predictive value of plasma proteomics in the long-term risk of PAD among individuals initially free of diabetes. METHODS: Included were 46 508 participants (6046 with prediabetes) without diabetes or major cardiovascular disease at recruitment of the UK Biobank. Using multivariable Cox regression models, a total of 2923 unique plasma proteins were assessed for the associations with incident PAD. Significant proteins were subsequently processed by a trained light gradient boosting machine classifier to determine important proteins. Using receiver operating characteristic analyses, the performance of these important proteins in predicting incident PAD were evaluated, in the whole sample and by glycemic status (normoglycemia and prediabetes). RESULTS: During a median follow-up of 12.7 years, 461 participants developed PAD. There were 107 proteins associated with incident PAD, with 103 positive associations. The LGBM approach identified 9 proteins (eg, WFDC2 [WAP 4-disulfide core domain protein 2], MMP12 [macrophage metalloelastase], and GDF15 [growth differentiation factor 15]) as the top-ranked proteins based on their importance ordering. Whereas glycated hemoglobin showed very modest predictive accuracy, a panel incorporating these top proteins showed good performance in the prediction of PAD risk (area under the curve 0.820), and it significantly enhanced the prediction beyond traditional risk factors (raising area under the curve from 0.803 to 0.837, DeLong test P=5.21×10-3). These observations were consistent for participants with normoglycemia or prediabetes. CONCLUSIONS: Plasma protein biomarkers enhance the prediction of long-term risk for PAD among individuals without diabetes, regardless of glycemic status.

Humans↗

PubMed2025

Emerging biomarkers in ischemic stroke.

Ischemic stroke is a devastating global public health problem and the leading cause of acute death and chronic disability. Despite being the diagnostic cornerstone, limitations in neuroimaging, including availability, cost, and therapeutic window, have rekindled interest in biomarker-based approaches. Biomarkers will be employed to facilitate the eventual prediction, early diagnosis, and prognosis of strokes, as well as to inform person-centered medicine. This review summarizes recent advances in the search for biomarkers related to inflammatory, endothelial, metabolic, and neuroaxonal pathways. Interleukin-6 (IL-6), asymmetric dimethylarginine (ADMA), endothelial microparticles (EMP), and homocysteine serve as predictive biomarkers corresponding to vascular risk and inflammatory priming. Glial fibrillary acidic protein (GFAP), D-dimer, and neuron-specific enolase (NSE) are diagnostic markers that can already subtype stroke and estimate lesion burden. Prognostic biomarkers, such as serum neurofilament light chain (sNfL), N-terminal pro-B-type natriuretic peptide (NT-pro-BNP), and growth differentiation factor 15 (GDF-15), are associated with infarct size and long-term outcomes. The -omic sciences (genomic, proteomic, and metabolomic) have discovered defined molecular signatures and panels with high specificity to describe heterogeneity in stroke. Cerebrospinal fluid (CSF) biomarkers and newer imaging modalities, such as those provided through positron emission tomography/computed tomography (PET/CT), offer valuable adjuncts to blood biomarkers in the diagnosis of conditions. Translational potential is hindered by heterogeneity in the transcriptional landscape.

Ischemic stroke↗

PubMed2026

Genome-wide characterization of the TGF-β superfamily identifies bmp15, gdf9, and gsdf as sex-biased candidate regulators of gonadal differentiation in the synchronous hermaphrodite Plectropomus leopardus.

The transforming growth factor-β (TGF-β) superfamily plays conserved roles in vertebrate reproduction and gonadal sex differentiation. However, its genomic repertoire and sex-biased expression patterns remain unclear in the leopard coral grouper (Plectropomus leopardus), a species with synchronous hermaphroditism. Here, we performed a genome-wide identification of the TGF-β superfamily, identifying 42 genes from the chromosome-level genome. Phylogenetic and synteny analyses indicated that segmental duplication under purifying selection contributed to family expansion. Expression profiling across multiple tissues and four gonadal developmental stages (undifferentiated, 120 dph; early differentiated, 15 months; mature testis, 3 years; mature ovary, 3 years) identified eight gonad-enriched genes, among which bmp15 and gdf9 exhibited pronounced female-biased expression, with transcripts localized exclusively to the oocyte cytoplasm, particularly in stage II-III oocytes. In contrast, gsdf showed male-biased expression and was localized in spermatogenic cells of the testis. These reciprocal expression patterns indicate that bmp15/gdf9 and gsdf are candidate factors associated with gonadal sex differentiation. Our study provides the first comprehensive characterization of the TGF-β superfamily in P. leopardus and highlights bmp15, gdf9, and gsdf as candidate sex-differentiation factors in this hermaphroditic species.

Animals↗

PubMed2026

Transpulmonary proteomic gradient analysis in women with pulmonary arterial hypertension associated with systemic sclerosis.

This study investigated proteomic alterations in the pulmonary circulation of patients with pulmonary arterial hypertension associated with systemic sclerosis (PAH-SSc) by analyzing the transpulmonary protein gradient and comparing the proteomic profiles with systemic sclerosis (SSc) without PAH. Twenty women were included (10 PAH-SSc, 64.6 ± 10.8 years; 10 SSc, 62.8 ± 11.5 years). The transpulmonary gradient was defined as the difference in biomarker concentrations between wedge-position and pulmonary artery blood samples. Peptides were analysed using liquid chromatography-mass spectrometry, and differentially abundant proteins were identified with Proteome Discoverer. Protein-protein interaction networks were generated with STRING and visualized in Cytoscape. A total of 270 proteins were detected, with no significant transpulmonary gradient alterations. However, patients with PAH-SSc showed distinct proteomic profiles compared to SSc. Multivariate analysis identified 48 differentially abundant proteins in pulmonary artery plasma, with 15 overrepresented and 33 downregulated in PAH-SSc. Among these, the downregulation of transforming growth factor-beta-induced protein ig-h3 (TGFβI/ig-h3) points to a potential involvement of the TGF-β-related extracellular matrix remodelling pathway in PAH-SSc. However, further validation in larger and independent cohorts is required before its relevance as a biomarker or therapeutic target can be established. In conclusion, while no transpulmonary proteomic gradient was observed, the proteomic profiles of PAH-SSc and SSc were different. The profile in PAH-SSc was characterized by differences in immune response, lipid metabolism, and hemostatic proteins. SIGNIFICANCE: This study offers the first proteomic characterization of the transpulmonary gradient in PAH-SSc and SSc. Although no differences in the gradient were found, the pulmonary artery plasma proteome of PAH-SSc patients showed a distinct pattern compared to SSc. Several proteins associated with immune function, haemostasis, and cellular processes were altered, which may indicate specific pathophysiological features of PAH-SSc or suggest how lung dysfunction develops in SSc. Targeting dysregulated proteins like TGFβI/ig-h3 or addressing immune-coagulation imbalances may support future research studies. Overall, these findings refine the molecular profile of PAH-SSc and provide a basis for future large-scale studies aimed at clarifying disease mechanisms and identifying clinically relevant molecular signatures.

Humans↗

PubMed1978

[Regulator of expression of the brachypodism-H gene in mice].

Extracts were prepared from the whole limb buds of the 11 day-old mouse embryos and from the postaxial or preaxial parts of the 12 day-old embryo limb buds. Effects of these extracts on the growth of the 13 day-old bpH/bpH embryo tibia rudiments were studied in vitro. It was shown that the limb buds of the 11- and 12 day-old mouse embryos contain a factor regulating bpH gene expression in differentiating cartilage cells. This factor is present in the postaxial part of the limb bud and is absent in its preaxial one. When the extract from the limb bud postaxial parts of the 12 day-old +/+ embryos is added to culture medium, the expression of bpH gene is observed in cultured tibia rudiments of the 13 day-old bpH/bpH embryos. The extraxt from the limb bud preaxial parts of the 12 day-old +/+ embryos does not affect the growth of tibia rudiments of mutant embryos in vitro. The regulator factor does not induce bpH gene expression in cultured bone rudiments of the 14 day-old bpH/bpH embryos. It is obvious that bpH locus does not act in cartilage cells of developing tibia after the 14th day of embryogenesis. The sensitivity of the factor regulating bpH gene expression to heating and proteolytic enzymes suggests its protein nature. The molecular weight of this protein is from 15 000 to 25 000. Experiments with actinomycin D show that this factor regulates the expression of bpH at the post-transcriptional level.

Achondroplasia↗

PubMed1975

Culture and morphological observations on Trypanosoma melphagium.

The cultural characteristics of Trypanosoma melophagium of sheep were studied. Aspects investigated were size of the inoculum and population growth in Modified Monophasic Medium for Trypanosomes (MMMT), population growth in Medium 199 with 10% inactivated calf serum containing 5, 10, and 15% hemolyzed defibrinated rabbit blood (199-CS-5, 199--CS-10, 199-CS-15) at 27 degrees C, effects on population growth of temperature and hydrogen ion concentration in MMMT, and morphology and morphometrics of the developmental stages found under different experimental conditions. The best growth occurred in medium MMMT at 30 degrees, C, pH 7.25. Temperature seemed to be a critical factor for differentiation of epimastigotes to trypomastigotes. Statistically significant differences were found between the trypomastigotes in MMMT and 199--cs-5 at 37 degrees C on day 4 of incubation for the following measurements: PK (distance from posterior end to kinetoplast), KN (from kinetoplast to middle of nucleus), PN (from posterior end to middle of nucleus), and nuclear and kinetoplastic indices. The trypomastigotes formed in both media were much smaller in size than the blood forms reported by Hoare (1972).

Animals↗

PubMed1976

Regulation of immunity and inflammation by mediators from macrophages.

Mononuclear phagocytes secrete a number of materials into the extracellular environment. The materials secreted by phagocytes can be grouped into three categories: a) enzymes affecting extracellular proteins (collagenase, elastase, lysosomal proteases, plasminogen activators), b) materials involved in defense processes (complement proteins, interferons, lysozyme), and c) factors regulating activities of surrounding cells. The latter include lymphostimulatory molecules, a colony-stimulating factor, and inhibitors of cell growth. The conditions for secretion of the materials depend on the activity of the phagocytes. The lymphostimulatory molecules secreted by macrophages exert various effects: 1) an increase in DNA synthesis of lymphocytes, 2) a maturation of early thymocytes to mature T cells, and 3) the differentiation of some B cells to antibody-secreting cells. The mitogenic principle has been partially isolated as a protein of 15,000 to 20,000 daltons. The secretion of lymphostimulatory molecules is increased following uptake of various materials by macrophages or by addition of activated T cells to macrophage cultures.

Animals↗

PubMed1979

Differential protection of normal and malignant tissues against the cytotoxic effects of mechlorethamine.

The radioprotective drug, WR-2721 (S,2-[3-aminopropylamino]ethyl-phosphorothioic acid), has been studied in terms of its ability to (a) protect mice against mechlorethamine (HN2)-induced hematopoietic death, and (b) alter the ability of HN2 injections to induce growth delay in a solid tumor, the Line 1 lung carcinoma. When WR-2721 was injected ip 15 minutes before iv injections of HN2, it increased resistance to hematopoietic death by a factor of 2, and the protection declined with a half-life of 1.5-2.0 hours. Similar administration of both drugs failed to alter the responsiveness of the Line 1 lung carcinoma to HN2-induced growth delays, except when the HN2 was given within 15 minutes after WR-2721. This interaction of the two drugs, when given within 5-15 minutes of each other, does not appear to be true protection at the tumor site, but rather appears to result from HN2 inactivation in the blood. When HN2 is given 30-60 minutes after WR-2721, it is possible to obtain a twofold increase in the tumor delay without risking increased hematopoietic injury.

Amifostine↗

PubMed1978

Different colony stimulating activity by tumoral ascitic fluid and conditioned media.

The effects of intraperitoneal Ehrlich ascites tumor (ET) growth on the kinetics of hemopoietic stem cells in the host bone marrow were studied using the spleen colony and the soft agar culture techniques. There is a decrease in spleen colony forming capacity of bone marrow of ET bearing mice, whereas in vitro assays of the committed macrophage granulocyte precursors, by the soft agar method, show that in the same circumstances a high yield of granulopoietic colonies can still be obtained. A shift of the CFU-c/CFU-s ratio from 15 to 36 thus occurs. Moreover, ascitic fluid from tumoral mice displays strong activity as CSF on normal mouse marrow, twice as strong as the standard mouse embryo CSF. When conditioned medium from cultures of ET cells (ET-CM) is tested, the pattern of agar colonies obtained is different from the previously obtained pattern of growth kinetics; furthermore many colonies are composed of undifferentiated cells. The hypothesis is suggested that among the variety of known CSF's, the ET-CM represents a unique factor, capable of inducing proliferation of marrow CFU-c, but only limited differentiation.

Animals↗

PubMed1976

[Golgi-Cox study of the distribution of dendritic spines in the cerebral cortex of the kitten. Part 1. The first 15 days of the postnatal period].

In order to study quantitatively the development of dendritic spines of pyramidal neurones, the suprasylvian cortex of kittens (1 to 15 days of age) was fixed and embedded by the Golgi-Cox (Sholl) method. The spines seen at different cortical levels were counted to establish their distribution along apical and basal dendrites. Disposition of spine contacts varied during the first month of post-natal cortical development. three periods were established in relation to the morphological growth of neurones. The first period(days 6 to 9), showed better defined layers and differentiation of spines in areas of maximal density. The third period (days 10 to 15) was defined by a remarkable enlargment of cellular processes, neural stratification and spinal distribution comparable to that of adult animals, although with a smaller number of spines. It is concluded that the organization of dendritic spines is closely related to neuronal development, coinciding with the initiation of cortical afferent systems.

Age Factors↗

PubMed1979

Rapid, sequential changes in surface morphology of PC12 pheochromocytoma cells in response to nerve growth factor.

The effect of nerve growth factor (NGF), a substance that promotes the differentiation and maintenance of certain neurons, was studied via scanning electron microscopy utilizing the PC12 clonal NGF-responsive pheochromocytoma cell line. After 2-4 d of exposure to NGF, these cells acquire many of the properties of normal sympathic neurons. However, by phase microscopy, no changes are discernible within the first 12-18 h. Since the primary NGF receptor appears to be a membrane receptor, it seemed likely that some of the initial responses to the factor may be surface related. PC12 cells maintained without NGF are round to ovoid and have numerous microvilli and small blebs. After the addition of NGF, there is a rapidly initiated sequential change in the cell surface. Ruffles appear over the dorsal surface of the cells with 1 min, become prominent by 3 min, and almost disappear by 7 min. Microvilli, conversely, disappear as the dorsal ruffles become prominent. Ruffles are seen at the the periphery of cell at 3 min, are prominent on most of the cells by 7 min and are gone by 15 min. The surface remains smooth from 15 min until 45 min when large blebs appear. The large blebs are present on most cells at 2 h and are gone by 4 h. The surface remains relatively smooth until 6-7 h of NGF treatment, when microvilli reappear as small knobs. These microvilli increase in both number and length to cover the cell surface by 10 h. These changes were not observed with other basic proteins, with alpha-bungarotoxin (which binds specifically to PC12 membranes), and were not affected by an RNA synthesis inhibitor that blocks initiation of neurite outgrowth. Changes in the cell surface architecture appear to be among the earlist NGF responses yet detected and may represent or reflect primary events in the mechanism of the factor's action.

Animals↗