The association between HIV-1 Tat and Vif amino acid sequence variation, inflammation and Trp-Kyn metabolism: an exploratory investigation.

BACKGROUND: HIV-1 has well-established mechanisms to disrupt essential pathways in people with HIV, such as inflammation and metabolism. Moreover, diversity of the amino acid sequences in fundamental HIV-1 proteins including Tat and Vif, have been linked to dysregulating these pathways, and subsequently influencing clinical outcomes in people with HIV. However, the relationship between Tat and Vif amino acid sequence variation and specific immune markers and metabolites of the tryptophan-kynurenine (Trp-Kyn) pathway remains unclear. Therefore, this study aimed to investigate the relationship between Tat/Vif amino acid sequence diversity and Trp-Kyn metabolites (quinolinic acid (QUIN), Trp, kynurenic acid (KA), Kyn and Trp/Kyn ratio), as well as specific immune markers (sCD163, suPAR, IL-6, NGAL and hsCRP) in n = 67 South African cART-naïve people with HIV. METHODS: Sanger sequencing was used to determine blood-derived Tat/Vif amino acid sequence diversity. To measure Trp-Kyn metabolites, a LC-MS/MS metabolomics platform was employed using a targeted approach. To measure immune markers, Enzyme-linked immunosorbent assays and the Particle-enhanced turbidimetric assay was used. RESULTS: After adjusting for covariates, sCD163 (p = 0.042) and KA (p = 0.031) were higher in participants with Tat signatures N24 and R57, respectively, and amino acid variation at position 24 (adj R2 = 0.048, ß = -0.416, p = 0.042) and 57 (adj R2 = 0.166, ß = 0.535, p = 0.031) of Tat were associated with sCD163 and KA, respectively. CONCLUSIONS: These preliminary findings suggest that amino acid variation in Tat may have an influence on underlying pathogenic HIV-1 mechanisms and therefore, this line of work merits further investigation.

[Genomic profiles and immune microenvironment of olfactory neuroblastoma].

Objective: To investigate the genomic profiles and immune microenvironment of olfactory neuroblastoma (ONB). Methods: Nineteen ONB cases diagnosed in the Beijing Tongren Hospital from May 2018 to October 2022 were divided into low-grade and high-grade groups according to the Hyams grading system, including 7 low-grade and 12 high-grade ONB. Whole exome sequencing and multiplex immunofluorescence analyses were performed on tissue samples of these ONB. Results: A total of 929 nonsynonymous alterations were identified in 18 of the 19 ONB (18/19) cases. The most commonly altered cancer-related genes were CTNNB1 (3/19) and ZNRF3 (3/19). The most mutated oncogenic pathways were the WNT and RAS pathways. The median tumor mutation burden (TMB) was 0.45/Mb, ranging from 0 to 3.25. The median tumor neoantigen load (TNB) was 9.39 neoantigens/Mb, ranging from 0 to 38.30. The median allelic mutation tumor heterogeneity (MATH) score was 16.95, ranging from 3.05 to 117.47. Only one of the 19 cases expressed PD-L1 (composite positive score, CPS>1) in the tumor cells. The median percentage of CD8+ tumor-infiltrating lymphocyte (TIL) in the tumor region was 1.08%. No significant differences were observed between the low-and high-grade groups for mutant genes, mutant pathways, TMB, TNB, MATH, PD-L1 expression levels, or CD8+ TILs percentage(P>0.05). However, the low-grade group showed significantly more CD68+ macrophages in both the tumor and total region than the high-grade group. Notably, CD68+CD163- macrophages accounted for an average of 80.52% of CD68+ macrophages. Conclusions: CTNNB1 and ZNRF3 are the most commonly altered cancer-related genes. The low expression of PD-L1 and the low percentage of CD8+ TIL indicate that ONB might not be sensitive to immunotherapy. The percentage of M1-type macrophages in low-grade ONB is significantly higher than that in high-grade ONB, suggesting that M1-type macrophages may be involved in the progression of ONB from low-grade to high-grade.

The role of M1 (CD11c) and M2 (CD163) interplay in the pathogenesis of oral submucous fibrosis and its malignant transformation: An immunohistochemical analysis.

OBJECTIVES: The M1/M2 macrophage framework is crucial in organ fibrosis and its progression to malignancy. This study investigated the possible role of M1/M2 macrophage interplay in the pathogenesis of oral submucous fibrosis (OSF) and its malignant transformation by analysing immunohistochemical expression of CD11c (M1) and CD163 (M2) markers. METHODS: Immunohistochemistry was performed using primary antibodies against CD11c and CD163 on ten formalin-fixed paraffin-embedded tissue blocks for each group: (i) Stage 1 OSF, (ii) Stage 2 OSF, (iii) Stage 3 OSF, (iv) Stage 4 OSF, (v) well-differentiated squamous cell carcinoma (WDSCC) with OSF, and (vi) WDSCC without OSF. Ten cases of healthy buccal mucosa (NOM) served as controls. RESULTS: Epithelial quick scores of M1 (CD11c) in NOM, Stages 1-4 OSF, and WDSCC with and without OSF were 0, 1.8, 2.9, 0.4, 0, 0, and 0, while connective tissue scores were 0, 3.2, 4.3, 2.7, 0.5, 1.2, and 2.4, respectively. Epithelial scores for M2 (CD163) were 0, 0.8, 0.8, 2.1, 0.6, 0.8, and 0.2, and connective tissue scores were 0, 1.8, 2.6, 3.9, 2.2, 5, and 4.4, respectively. Stages 3 and 4 OSF, WDSCC with and without OSF exhibited higher M2/M1 ratios compared to NOM and Stages 1-2 OSF. CONCLUSION: The interaction between M1 (CD11c) and M2 (CD163) macrophages, leading to M2 polarisation, plays a crucial role in the pathogenesis of OSF and its potential malignant transformation.

Comparative immunohistochemical expression of Beta catenin and CD163 between dysplastic / non-dysplastic oral lichen planus and lichenoid lesions (EX-VIVO STUDY).

BACKGROUND: Oral lichen planus is a well-known chronic inflammatory mucocutaneous disorder, which has clinical and histological presentation that mimics oral lichenoid reaction. According to the fifth edition of WHO, both conditions are considered as oral potentially malignant disorders. Recent studies on oral potential disorders documented deregulation of some signaling molecules related to the Wnt/ß-catenin pathway. Therefore this study aimed to compare the immune expression of ß-catenin & CD163 in dysplastic /non-dysplastic cases of Oral lichen planus & oral lichenoid lesion. In addition, a statistical correlation between both immune markers was done regardless of the type of the study group. METHODS: Four study groups were designated as 2 groups of Oral lichen planus (one dysplastic & one non -dysplastic) and the other 2 groups were oral lichenoid lesions (one dysplastic & one non -dysplastic). Ten cases in each group were collected and investigated by immunohistochemistry. The area percent of beta catenin and also counting of m2 macrophages expressing + CD163 marker was calculated in the study groups. RESULTS: The Statistical analysis highlighted a statistically significant difference between the studied groups. Moreover, Pearson correlation test reported a significant moderate positive correlation between beta catenin & CD163 expression in the studied cases. CONCLUSION: Our findings supported new perceptions of the mechanism by which tumor associated macrophage specific ß-catenin signaling promotes the aggressive behavior of oral potential malignant disorders. CLINICAL RELEVANCE: Evidence of the relationship between beta catenin and M2 macrophages (+ CD163) may enhance the development of macrophage-based strategies for treatment and improve the prognosis of such cases.

Potential Impact of Omega 6/3 Ratio and CD68+ Macrophage Infiltration on Survival in NSCLC Patients Undergoing Pulmonary Resection.

Background: Lung cancer remains the leading cause of cancer-related mortality worldwide with non-small cell lung cancer (NSCLC) accounting for the majority of cases. The stage of detection significantly influences survival rates with early-stage diagnosis offering the best prognosis. This study investigates the prognostic impact of the omega-6/omega-3 ratio and tumor infiltration by CD8+ lymphocytes and CD68+ macrophages on overall survival (OS) and disease-free survival (DFS) in NSCLC patients undergoing pulmonary resection. Methods: We conducted a retrospective analysis of 53 patients with early-stage NSCLC who underwent pulmonary resection between September 2017 and January 2020. The omega-6/omega-3 ratio was quantified using gas chromatography and spectrometry. Tumor infiltration by CD8 and CD68 was assessed through immunohistochemistry. Survival outcomes were evaluated using Kaplan-Meier and Cox regression analyses. Results: An increased omega-6/omega-3 ratio and higher CD68+ macrophage infiltration were associated with a trend towards worse OS and DFS in NSCLC patients, though these results did not reach statistical significance. CD8+ T-cell infiltration was associated with improved survival outcomes, confirming its role as a favorable prognostic marker. Comparative analysis with existing datasets revealed similar demographic and clinical characteristics, reinforcing the generalizability of our findings. Conclusions: The omega-6/omega-3 ratio and CD68+ macrophage infiltration serve as important factors potentially influencing prognosis in NSCLC patients undergoing pulmonary resection. These findings highlight the need for further research to refine the prognostic utility of these biomarkers and to explore therapeutic strategies targeting inflammation and immune cell infiltration.

Increased Parenchymal Macrophages are associated with decreased Tyrosine Hydroxylase mRNA levels in the Substantia Nigra of people with Schizophrenia and Bipolar Disorder.

Increased activation of inflammatory macrophages and altered expression of dopamine markers are found in the midbrains of people with schizophrenia (SZ). The relationship of midbrain macrophages to dopamine neurons has not been explored, nor is it known if changes in midbrain macrophages are also present in bipolar disorder (BD) or major depressive disorder (MDD). Herein, we determined whether there were differences in CD163+ cell density in the Substantia Nigra (SN), and cerebral peduncles (CP) of SZ, BD, and MDD compared to controls (CTRL). We also analyzed whether CD163 protein and dopamine-synthesizing enzyme tyrosine hydroxylase (TH) mRNA levels differed among diagnostic groups and if they correlated with the density of macrophages. Overall, perivascular CD163+ cell density was higher in the gray matter (SN) than in the white matter (CP). Compared to CTRL, we found increased density of parenchymal CD163+ cells in the SN of the three psychiatric groups and increased CD163 protein levels in SZ. CD163 protein was positively correlated with density of perivascular CD163+ cells. TH mRNA was reduced in SZ and BD and negatively correlated with parenchymal CD163+ cell density. We provide the first quantitative and molecular evidence of an increase in the density of parenchymal macrophages in the midbrain of major mental illnesses and show that the presence of these macrophages may negatively impact dopaminergic neurons.

The impact of synbiotic on serum sCD163/sTWEAK, paraoxonase 1, and lipoproteins in patients with chronic heart failure: a randomized, triple-blind, controlled trial.

Cardiovascular disease is one of the leading causes of death worldwide. Evidence suggests that alterations in the gut microbiome could play a role in cardiovascular diseases, including heart failure. The purpose of this study was to evaluate the effect of synbiotics on serum paraoxonase 1(PON1), soluble CD163/soluble TNF-like weak inducer of apoptosis (sCD163/sTWEAK), and lipid profile, which are involved in heart failure in patients with chronic heart failure. In this triple-blind randomized clinical trial, 90 eligible patients were included in the study. They were randomly assigned to receive one capsule (500 mg) of synbiotics or a placebo daily for ten weeks. Serum PON1, sCD163/sTWEAK, and lipid profiles were measured at the beginning and end of the study. The data were analyzed by SPSS 24, and the p-value < 0.05 was considered statistically significant. Among 90 patients who met the inclusion criteria, 80 completed the study. The primary outcomes showed a small effect on sTWEAK, with an adjusted standard mean difference (SMD) of 0.2. However, no significant changes were observed in sCD163/sTWEAK (SMD: 0.16). Secondary outcomes indicated no changes in PON1, total cholesterol (TC), or LDL-C levels. However, there was an increase in HDL-C levels (adjusted SMD: 0.46, 95% CI: 0.02-0.91) and a decrease in TG and TC/HDL levels (adjusted SMD: - 0.5 and - 0.3, respectively) in the synbiotic group. A favorable effect of synbiotics on sTWEAK, HDL, TG, and TC/HDL of patients with heart failure was observed, but no statistically significant effect was found on sCD163/sTWEAK, PON1, LDL, and TC factors.

High expression of SIGLEC7 may promote M2-type macrophage polarization leading to adverse prognosis in glioma patients.

Introduction: Gliomas are the most common primary intracranial tumors, known for their high invasiveness and destructiveness. Sialic acid-binding immunoglobulin-like lectin 7 (SIGLEC7) is present in various immune cells, especially macrophages, and significantly affects immune homeostasis and cancer cell response. However, research on the role and prognostic impact of SIGLEC7 in glioma patients is currently limited. Methods: We utilized transcriptomic data from 702 glioma patients in The Cancer Genome Atlas (TCGA) and 693 glioma patients in the Chinese Glioma Genome Atlas (CGGA), along with clinical samples we collected, to comprehensively investigate the impact of SIGLEC7 on glioma expression patterns, biological functions, and prognostic value. We focused on its role in glioma-related immune responses and immune cell infiltration and analyzed its expression at the single-cell level. Finally, we validated the role of SIGLEC7 in gliomas through tissue and cell experiments. Results: SIGLEC7 expression was significantly increased in glioma patients with malignant characteristics. Survival analysis indicated that glioma patients with high SIGLEC7 expression had significantly lower survival rates. Gene function analysis revealed that SIGLEC7 is primarily involved in immune and inflammatory responses and is strongly negatively correlated with tumor-associated immune regulation. Additionally, the expression of most immune checkpoints was positively correlated with SIGLEC7, and immune cell infiltration analysis clearly demonstrated a significant positive correlation between SIGLEC7 expression and M2 macrophage infiltration levels. Single-cell analysis, along with tissue and cell experiments, confirmed that SIGLEC7 enhances macrophage polarization towards the M2 phenotype, thereby promoting glioma invasiveness through the immunosuppressive effects of M2 macrophages. Cox regression analysis and the establishment of survival prediction models indicated that high SIGLEC7 expression is an unfavorable prognostic factor for glioma patients. Discussion: High SIGLEC7 expression predicts poor prognosis in glioma patients and is closely associated with M2 macrophages in the tumor environment. In the future, SIGLEC7 may become a promising target for glioma immunotherapy.

Integrated Analysis of Phagocytic and Immunomodulatory Markers in Cervical Cancer Reveals Constellations of Potential Prognostic Relevance.

Despite improvements in vaccination, screening, and treatment, cervical cancer (CC) remains a major healthcare problem on a global scale. The tumor microenvironment (TME) plays an important and controversial role in cancer development, and the mechanism of the tumor's escape from immunological surveillance is still not clearly defined. We aim to investigate the expression of CD68 and CD47 in patients with different histological variants of CC, tumor characteristics, and burden. This is a retrospective cohort study performed on paraffin-embedded tumor tissues from 191 patients diagnosed with CC between 2014 and 2021 at the Medical University Pleven, Bulgaria. Slides for immunohistochemical (IHC) evaluation were obtained, and the expression of CD68 was scored in intratumoral (IT) and stromal (ST) macrophages (CD68+cells) using a three-point scoring scale. The CD47 expression was reported as an H-score. All statistical analyses were performed using R v. 4.3.1 for Windows. Infiltration by CD68-IT cells in the tumor depended on histological type and the expression of CD47. Higher levels of the CD47 H-score were significantly more frequent among patients in the early stage. Higher levels of infiltration by CD68-ST cells were associated with worse prognosis, and the infiltration of CD68-IT cells was associated with reduced risk of death from neoplastic disease. TME is a complex ecosystem that has a major role in the growth and development of tumors. Macrophages are a major component of innate immunity and, when associated with a tumor process, are defined as TAM. Tumor cells try to escape immunological surveillance in three ways, and one of them is reducing immunogenicity by the overexpression of negative coreceptors by T-lymphocytes and their ligands on the surface of tumor cells. One such mechanism is the expression of CD47 in tumor cells, which sends a "don't eat me" signal to the macrophages and, thus, prevents phagocytosis. To our knowledge, this is the first study that has tried to establish the relationship between the CD47 and CD68 expression levels and some clinicopathologic features in CC. We found that the only clinicopathological feature implicating the level of CD68 infiltration was the histological variant of the tumor, and only for CD68-IT-high levels were these observed in SCC. High levels of CD47 expression were seen more frequently in pT1B than pT2A and pT2B in the FIGO I stage than in the FIGO II and III stages. Infiltration by large numbers of CD68-IT cells was much more common among patients with a high expression of CD47 in tumor cells. A high level of infiltration by CD68-ST cells was associated with a worse prognosis, and a high level of infiltration by CD68-ST cells was associated with a lower risk of death from cancer.

Relationship of microvascular density and tumor-associated macrophages with orofacial squamous cell carcinoma progression.

OBJECTIVE: The current study aimed to investigate the characteristics of tumor-associated macrophages (TAMs) and their association with microvascular density (MVD) in tumor progression in different grades of orofacial squamous cell carcinoma (OSCC) in the Pakistani population. STUDY DESIGN: This prospective study included 234 patients with oral cancer reported at different hospitals in Pakistan diagnosed with OSCC. Tumors were graded on the Anneroth grading system and the association between the frequency of TAMs and MVD was examined in vivo. The macrophages visible through immunohistochemistry for CD68 and the microvessels observed through immunohistochemistry for CD34 were manually counted in 3 high-power fields. RESULTS: The CD68 and CD34 counts were significantly lower in well-differentiated squamous cell carcinoma compared to poorly differentiated squamous cell carcinoma. Linear regression analysis revealed a positive correlation between the area percentage of CD68 immunoreactivity and the grade of the tumor (r = 0.776). Vice versa, a positive correlation also existed between the area percentage of CD34 immunoreactivity and the grade of the tumor (r = 0.690). Pearson correlation revealed a positive association between the TAMs and MVD (r = 0.680; P < .001). CONCLUSIONS: There was an increased population of tumor-associated macrophages and tumor angiogenesis with the increasing grade of orofacial squamous cell carcinoma. (Oral Surg Oral Med Oral Pathol Oral Radiol YEAR;VOL:page range).

Clinical significance of serum soluble scavenger receptor CD163 in patients with lupus nephritis.

BACKGROUND: The soluble CD163 (sCD163) was elevated in systemic lupus erythematosus (SLE) patients. PURPOSE: To study whether serum sCD163 could be used to predict the occurrence and prognosis of lupus nephritis (LN). RESEARCH DESIGN: The recruited patients were classified into different groups according to standard identification criteria. STUDY SAMPLE: The patients with LN. DATA COLLECTION AND ANALYSIS: 11 indices were analyzed and compared in SLE and LN patients. Furthermore, the level of serum sCD163 was detected using an enzyme-linked immunosorbent assay. Meanwhile, the receiver operating characteristic analysis was performed to evaluate the prediction effect of sCD163. Additionally, spearman correlation analysis of serum sCD163 with indices was conducted. RESULTS: There were six positive indices and one negative risk factor correlated to LN. sCD163 was elevated in LN patients and could be used to diagnose LN. Importantly, sCD163 was increased in LN patients with a heavy SLE disease activity index. Finally, it was revealed that the level of sCD163 was higher in the LN patients with no response than that with complete or partial response, which also could predict the prognosis of LN. CONCLUSIONS: Serum sCD163 was elevated in LN patients than in SLE patients, which could be used to predict the occurrence and prognosis of LN.

Circulating soluble CD163 is associated with reduced Glasgow Coma Scale Score and 1-year all-cause mortality in traumatized patients.

Soluble CD163 (sCD163) is a biomarker of macrophage activation, not previously investigated in the circulation of traumatized patients. A biobank of 398 adult trauma patients was analyzed. Patients with an Injury Severity Score (ISS) >8 served as trauma patients (n = 195) and those with ISS ≤8 as trauma controls (n = 203). Serum samples obtained upon admission, 15h and 72h after were analyzed for sCD163 using an in-house ELISA. Multiple linear regression was used to analyze the association between admission levels of sCD163 with, 1: overall trauma severity (ISS), and 2: severity of injury to specified organs using Abbreviated Injury Score (AIS) and Glasgow Coma Scale (GCS). The association between the peak level of sCD163 with 1-year all-cause mortality was analyzed by logistic regression analysis. Median admission levels of sCD163 were higher in trauma patients than trauma controls [2.32 (IQR 1.73 to 2.86) vs. 1.92 (IQR 1.41 to 2.51) mg/L, p < 0.01]. Worsening GCS score was associated with a 10.3% (95% CI: 17.0 to 3.1, p < 0.01) increase in sCD163. Increasing Head-AIS score was associated with a 5.1% (95% CI: -0.5 to 11.0, p = 0.07) increase in sCD163. The remaining AIS scores and ISS were not consistently associated with sCD163 admission levels. Each mg/L increase in sCD163 peak level had an odds ratio 1.34 (95%CI: 0.98 to 1.83), p = 0.06) after adjustment for age, sex, and GCS. Circulating sCD163 is increased in traumatized patients and associated with worsening GCS. Our findings suggest an association between circulating sCD163 levels with 1-year all-cause mortality.

Novel Immunohistochemical and Morphological Approaches in a Retrospective Study of Post-Mortem Myocarditis.

Background and Objectives: This study presents a retrospective analysis of 26 autopsy cases from a single centre, primarily focusing on forensic cases, with a majority of male individuals. Materials and Methods: We systematically analysed autopsy reports and cardiac tissue slides using haematoxylin-eosin stain and immunohistochemistry for CD3, CD163, and IL-6. The histological assessment evaluated key variables such as inflammation severity, necrosis, and background changes using a standardised grading system. Quantitative analysis of immunohistochemical markers was performed, calculating the percentage of positively stained cells within the inflammatory infiltrate. Results: The average age was 51.6 years, slightly skewed towards older males. The fatalities varied widely, with sudden death and drug abuse being the most common conditions linked to myocarditis findings on histological examination. A strong correlation was found between the severity of inflammation (measured by size within a myocardium section) and the scoring system based on the number of inflammatory foci per section (p ≤ 0.001). Most cases showed mild to minimal fibrosis, with some exhibiting moderate to severe fibrosis, arteriosclerosis, and myocyte hypertrophy. The presence of protein CD3 in the inflammatory infiltrate revealed a moderate inverse correlation between the CD3 values and the severity of inflammation and necrosis, and a strong inverse correlation with neutrophil levels. CD3 levels were higher in sudden death cases and lower in cases with numerous inflammatory foci, highlighting the discreet nature of lymphocytic myocarditis. Macrophage presence, assessed using CD163, showed a moderate inverse correlation with neutrophil levels and significant differences between sudden death and non-sudden death cases. Macrophage-rich inflammation was observed in cases with pneumonia/bronchopneumonia-associated lesions. IL-6 expression showed a moderate direct correlation with inflammation severity (p = 0.028), severity of necrosis (p = 0.005), and the number of inflammatory foci per section (p = 0.047). A moderate inverse correlation was found between CD3 and IL-6 expression (p = 0.005). Conclusions: These findings highlight the need for a unique immunohistochemical approach in forensic cases of myocarditis, differing from guidelines for endomyocardial biopsies due to diverse inflammatory cells. The study suggests exploring inflammatory chemokines within myocarditis foci for their significance in clinical scenarios. Specifically, IL-6, a crucial pro-inflammatory interleukin, correlated significantly with the severity of inflammation and necrosis (p < 0.05). This study provides novel and valuable insights into the histopathological and immunological markers of myocarditis in autopsy cases.

The potential of disulfiram as a drug to improve the prognosis after the onset of subarachnoid hemorrhage.

Subarachnoid hemorrhage due to rupture of intracranial aneurysms has a poor outcome, making this disease being the social problem. Inflammation evoked by the increase in intracranial pressure and the clot in the subarachnoid space after the onset of SAH exacerbates neuronal death and vasospasm, resulting in the poor outcome and severe aftereffects. Here, FROUNT mediates CCR2 and CCR5 signaling as an intracellular molecule binding to these chemoattractant receptors which facilitate the migration of inflammatory cells, such as macrophages, in situ to trigger inflammation there. Animal model of subarachnoid hemorrhage was established in rats through intrathecal injection of autologous blood. The effect of the FROUNT inhibitor, disulfiram, on survival rate, neuronal death in hippocampus or vasospasm was then examined. The intrathecal administration of disulfiram significantly suppressed the infiltration of CD68-positive macrophages and myeloperoxidase-positive neutrophils toward the clot in the cistern in situ. In this condition, disulfiram ameliorated the death of animals after the onset of subarachnoid hemorrhage in rats. In addition, disulfiram suppressed both the two major events after subarachnoid hemorrhage, the neuronal death in hippocampus and vasospasm. The pharmacological inhibition of CCR2 and CCR5 signaling by disulfiram could thus be the therapeutic strategy to improve the outcome of subarachnoid hemorrhage.

[Prognostic Value of LMR and CD163+TAM for Patients with Diffuse Large B Cell Lymphoma].

OBJECTIVE: To investigate the prognostic value of lymphocyte-to-monocyte ratio (LMR) and CD163+tumor-associated macrophages (TAM) in patients with diffuse large B cell lymphoma (DLBCL). METHODS: Peripheral blood and lymph node tissues were collected from 63 newly diagnosed DLBCL patients. LMR was calculated by the number of lymphocytes and monocytes in peripheral blood from the result of blood routine examination. The level of CD163+TAM in lymph nodes was detected by immunohistochemistry. The cut-off values of LMR and CD163+TAM were determined by ROC curves, and the prognostic value of LMR and CD163+TAM in DLBCL patients was analyzed. RESULTS: The LMR level of 63 newly diagnosed DLBCL patients was 3.69±1.71, and the median value of CD163+TAM was 26/HPF. The number of CD163+TAM was negatively correlated with LMR (r =-0.58) and positively correlated with monocyte count (r =0.46). The cut-off values of LMR and CD163+TAM determined by ROC curve were 2.95 and 29/HPF, respectively, and based on this, the patients were divided into low LMR group and high LMR group, as well as low CD163+TAM group and high CD163+TAM group. The proportion of patients with clinical stage III-IV, IPI score 3-5 and bone marrow infiltration in the low LMR group were higher than those in the high LMR group (P < 0.05). The proportion of patients with clinical stage III-IV, IPI score 3-5, elevated LDH level and bone marrow infiltration in the high CD163+TAM group were higher than those in the low CD163+TAM group (P < 0.05). There was a positive correlation between LMR and OS (r =0.43) and a negative correlation between CD163+TAM and OS (r =-0.65). DLBCL patients with low LMR and high CD163+TAM had shorter OS (P < 0.05). CONCLUSION: Low LMR and high CD163+TAM can be used as biological markers for poor prognosis of DLBCL patients.

PRRSV infection facilitates the shedding of soluble CD163 to induce inflammatory responses.

Porcine reproductive and respiratory syndrome (PRRS), which poses substantial threats to the global pig industry, is primarily characterized by interstitial pneumonia. Cluster of differentiation 163 (CD163) is the essential receptor for PRRSV infection. Metalloproteinase-mediated cleavage of CD163 leads to the shedding of soluble CD163 (sCD163), thereby inhibiting PRRSV proliferation. However, the exact cleavage site in CD163 and the potential role of sCD163 in inflammatory responses during PRRSV infection remain unclear. Herein, we found that PRRSV infection increased sCD163 levels, as demonstrated in primary alveolar macrophages (PAMs), immortalized PAM (IPAM) cell lines, and sera from PRRSV-infected piglets. With LC-MS/MS, Arg-1041/Ser-1042 was identified as the cleavage site in porcine CD163, and an IPAM cell line with precise mutation at the cleavage site was constructed. Using the precisely mutated IPAM cells, we found that exogenous addition of sCD163 protein promoted inflammatory responses, while mutation at the CD163 cleavage site suppressed inflammatory responses. Consistently, inhibition of sCD163 using its neutralizing antibodies reduced PRRSV infection-triggered inflammatory responses. Importantly, sCD163 promoted cell polarization from M2 to M1 phenotype, which in turn facilitated inflammatory responses. Taken together, our findings identify sCD163 as a novel proinflammatory mediator and provide valuable insights into the mechanisms underlying the induction of inflammatory responses by PRRSV infection.

CD163+ macrophages in mantle cell lymphoma induce activation of prosurvival pathways and immune suppression.

ABSTRACT: Mantle cell lymphoma (MCL) is dependent on a supportive tumor immune microenvironment (TIME) in which infiltration of CD163+ macrophages has a negative prognostic impact. This study explores how abundance and spatial localization of CD163+ cells are associated with the biology of MCL, using spatial multiomic investigations of tumor and infiltrating CD163+ and CD3+ cells. A total of 63 proteins were measured using GeoMx digital spatial profiling in tissue microarrays from 100 diagnostic MCL tissues. Regions of interest were selected in tumor-rich and tumor-sparse tissue regions. Molecular profiling of CD163+ macrophages, CD20+ MCL cells, and CD3+ T-cells was performed. To validate protein profiles, 1811 messenger RNAs were measured in CD20+ cells and 2 subsets of T cells. Image analysis was used to extract the phenotype and position of each targeted cell, thereby allowing the exploration of cell frequencies and cellular neighborhoods. Proteomic investigations revealed that CD163+ cells modulate their immune profile depending on their localization and that the immune inhibitory molecules, V-domain immunoglobulin suppressor of T-cell activation and B7 homolog 3, have higher expression in tumor-sparse than in tumor-rich tissue regions and that targeting should be explored. We showed that MCL tissues with more abundant infiltration of CD163+ cells have a higher proteomic and transcriptional expression of key components of the MAPK pathway. Thus, the MAPK pathway may be a feasible therapeutic target in patients with MCL with CD163+ cell infiltration. We further showed the independent and combined prognostic values of CD11c and CD163 beyond established risk factors.

Systemic inflammation attenuates the repair of damaged brains through reduced phagocytic activity of monocytes infiltrating the brain.

In this study, we examined how systemic inflammation affects repair of brain injury. To this end, we created a brain-injury model by stereotaxic injection of ATP, a damage-associated molecular pattern component, into the striatum of mice. Systemic inflammation was induced by intraperitoneal injection of lipopolysaccharide (LPS-ip). An analysis of magnetic resonance images showed that LPS-ip reduced the initial brain injury but slowed injury repair. An immunostaining analysis using the neuronal marker, NeuN, showed that LPS-ip delayed removal of dead/dying neurons, despite the fact that LPS-ip enhanced infiltration of monocytes, which serve to phagocytize dead cells/debris. Notably, infiltrating monocytes showed a widely scattered distribution. Bulk RNAseq analyses showed that LPS-ip decreased expression of genes associated with phagocytosis, with PCR and immunostaining of injured brains confirming reduced levels of Cd68 and Clec7a, markers of phagocytic activity, in monocytes. Collectively, these results suggest that systemic inflammation affects properties of blood monocytes as well as brain cells, resulting in delay in clearing damaged cells and activating repair processes.

Neisserial adhesin A (NadA) binds human Siglec-5 and Siglec-14 with high affinity and promotes bacterial adhesion/invasion.

Neisserial adhesin A (NadA) is a meningococcal surface protein included as recombinant antigen in 4CMenB, a protein-based vaccine able to induce protective immune responses against Neisseria meningitidis serogroup B (MenB). Although NadA is involved in the adhesion/invasion of epithelial cells and human myeloid cells, its function in meningococcal physiology is still poorly understood. To clarify the role played by NadA in the host-pathogen interaction, we sought to identify its cellular receptors. We screened a protein microarray encompassing 2,846 human and 297 mouse surface/secreted recombinant proteins using recombinant NadA as probe. Efficient NadA binding was revealed on the paired sialic acid-binding immunoglobulin-type lectins receptors 5 and 14 (Siglec-5 and Siglec-14), but not on Siglec-9 therein used as control. The interaction was confirmed by biochemical tools with the determination of the KD value in the order of nanomolar and the identification of the NadA binding site by hydrogen-deuterium exchange coupled to mass spectrometry. The N-terminal domain of the Siglec-5 that recognizes the sialic acid was identified as the NadA binding domain. Intriguingly, exogenously added recombinant soluble Siglecs, including Siglec-9, were found to decorate N. meningitidis surface in a NadA-dependent manner. However, Siglec-5 and Siglec-14 transiently expressed in CHO-K1 cells endorsed NadA binding and increased N. meningitidis adhesion/invasion while Siglec-9 did not. Taken together, Siglec-5 and Siglec-14 satisfy all features of NadA receptors suggesting a possible role of NadA in the acute meningococcal infection.IMPORTANCEBacteria have developed several strategies for cell colonization and immune evasion. Knowledge of the host and pathogen factors involved in these mechanisms is crucial to build efficacious countermoves. Neisserial adhesin A (NadA) is a meningococcal surface protein included in the anti-meningococcus B vaccine 4CMenB, which mediates adhesion to and invasion of epithelial cells. Although NadA has been shown to bind to other cell types, like myeloid and endothelial cells, it still remains orphan of a defined host receptor. We have identified two strong NadA interactors, Siglec-5 and Siglec-14, which are mainly expressed on myeloid cells. This showcases that NadA is an additional and key player among the Neisseria meningitidis factors targeting immune cells. We thus provide novel insights on the strategies exploited by N. meningitidis during the infection process, which can progress to a severe illness and death.

Genetically modified pigs with CD163 point mutation are resistant to HP-PRRSV infection.

Porcine reproductive and respiratory syndrome (PRRS) is a globally prevalent contagious disease caused by the positive-strand RNA PRRS virus (PRRSV), resulting in substantial economic losses in the swine industry. Modifying the CD163 SRCR5 domain, either through deletion or substitution, can eff1ectively confer resistance to PRRSV infection in pigs. However, large fragment modifications in pigs inevitably raise concerns about potential adverse effects on growth performance. Reducing the impact of genetic modifications on normal physiological functions is a promising direction for developing PRRSV-resistant pigs. In the current study, we identified a specific functional amino acid in CD163 that influences PRRSV proliferation. Viral infection experiments conducted on Marc145 and PK-15 CD163 cells illustrated that the mE535G or corresponding pE529G mutations markedly inhibited highly pathogenic PRRSV (HP-PRRSV) proliferation by preventing viral binding and entry. Furthermore, individual viral challenge tests revealed that pigs with the E529G mutation had viral loads two orders of magnitude lower than wild-type (WT) pigs, confirming effective resistance to HP-PRRSV. Examination of the physiological indicators and scavenger function of CD163 verified no significant differences between the WT and E529G pigs. These findings suggest that E529G pigs can be used for breeding PRRSV-resistant pigs, providing novel insights into controlling future PRRSV outbreaks.