Cancer-associated fibroblasts (CAFs) are principal determinants of pancreatic ductal adenocarcinoma (PDAC) progression. CAFs can shape tumor behavior via multiple pathways, underscoring the need for a complete understanding of the regulatory mechanisms that govern CAF function. Here, we identified N6-methyladenosine (m6A) remodeling as a hallmark of CAF activation and defined a critical role for the m6A demethylase ALKBH5 in PDAC metastasis. Activated CAFs exhibited a global reduction in m6A abundance, with ALKBH5 emerging as a key regulator of the CAF epitranscriptome. Functionally, CAF-derived ALKBH5 enhanced pancreatic cancer cell migration and invasion in vitro and promoted epithelial-mesenchymal transition-associated gene expression in tumor cells in an m6A-dependent manner. Orthotopic co-implantation models and host genetic ablation models demonstrated that ALKBH5 plays a critical role in metastatic dissemination, with minimal impact on primary tumor growth. Mechanistically, ALKBH5 enhanced the m6A-dependent translation of HSF1 in CAFs, at least in part by relieving IGF2BP3-associated translational constraints. Elevated HSF1 subsequently activated LIF transcription through distal enhancer elements, establishing an ALKBH5-HSF1-LIF signaling axis that mediated the pro-metastatic CAF-tumor cell communication. Clinically, enrichment of ALKBH5⁺HSF1⁺ CAFs independently predicted poor prognosis and was preferentially observed in metastatic PDAC. Collectively, these findings uncover a CAF-intrinsic epitranscriptomic program that drives PDAC metastasis and highlight stromal m6A regulation as a potential therapeutic vulnerability.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by a highly immunosuppressive and desmoplastic tumor microenvironment (TME) that limits the efficacy of immunotherapy. However, the evolution of this immunosuppressive TME and the underlying mechanisms remain incompletely understood. Here, we construct a dynamic single-cell atlas spanning uninvolved adjacent pancreatic tissue (UNIN), intraductal papillary mucinous neoplasm (IPMN), and PDAC. We confirm the stepwise establishment of an immunosuppressive milieu, accompanied by the emergence of LRRC15+ fibroblasts as determinants. Functional assays further identify tumor-derived LAMB3 as a regulator of LRRC15+ fibroblast differentiation. Mechanistically, LAMB3 promotes FOSL2-dependent transcriptional activation of LRRC15 through the ITGB1/FAK/MAPK signaling axis, ultimately suppressing T cell cytotoxicity. Orthotopic models reveal that LAMB3 overexpression increases the LRRC15 positive area and impairs T cell cytotoxicity, whereas FAK inhibition partially reverses these effects. In parallel, LAMB3 knockdown reduces the LRRC15 positive area and improves the efficacy of PD-1 blockade. Moreover, glycolytic reprogramming in PDAC ductal cells upregulates LAMB3 expression and correlates with increased LRRC15+ fibroblast enrichment. Clinically, co-enrichment of LAMB3+ PDAC ductal cells and LRRC15+ fibroblasts is associated with inferior overall survival. Collectively, our findings define a dynamic ductal-fibroblast-immune multicellular axis underlying PDAC pathogenesis and provide insights into potential therapeutic strategies.

c-Met overexpression may identify patients who benefit from MET inhibitor therapy. However, concordance among c-Met immunohistochemistry (IHC) assays and scoring system reliability remain unclear. We retrospectively analyzed 150 lung adenocarcinoma specimens (from December 2018 to March 2023) using 5 c-Met IHC assays (SP44R, SP44Z, D1C2, LBP4-C-MET, and 811B7F4), scored by H-score, clinical score, 2-tier H-score (H-score ≥150 as positive) and 2-tier clinical score (clinical score 2+/3+ as positive). Next-generation sequencing for MET alterations was performed on 107 samples. H-scores of the 5 assays showed excellent interassay reliability (intraclass correlation coefficient = 0.953). Compared with SP44R, which is the most frequently used antibody in the clinical trial, SP44Z had the highest correlation with it (ρ = 0.851), followed by D1C2 (ρ = 0.818), LBP4-C-MET (ρ = 0.786), and 811B7F4 (ρ = 0.737). Among the 5 assays, Kendall W for the clinical score was 0.697; Fleiss κ for the 2-tier H-score was 0.51 and for the 2-tier clinical score was 0.494. In comparison with the clinical score 3+ of SP44R, SP44Z and 811B7F4 showed moderate reliability (κ = 0.483), LBP4-C-MET (κ = 0.459), and D1C2 (κ = 0.234). Nearly perfect agreement existed between the 2-tier H-score and clinical score (κ range: 0.944-0.986). In contrast, correlation analysis between H-scores across all assays and RNA expression levels revealed a weak association (ρ = 0.159-0.349). Five c-Met IHC assays demonstrated moderate-to-strong concordance in detecting c-Met overexpression. SP44R, SP44Z, LBP4-C-MET, and 811B7F4 performed reliably, although D1C2 was less consistent for clinical score 3+. A clinical score of 2+/3+ or an H-score of ≥150 is associated with high diagnostic consistency, supporting multiple validated IHC assays for c-Met evaluation in lung adenocarcinoma.

HER2-targeted therapy is increasingly used in colorectal cancer (CRC). However, discrepancies between conventional detection methods (immunohistochemistry [IHC]/fluorescence in situ hybridization [FISH]) and next-generation sequencing (NGS) remain to be elucidated. Furthermore, the impact of spatial intratumoral heterogeneity (SIH) in HER2 overexpression on both the methodological concordance and therapeutic efficacy is still poorly understood. Two consecutive retrospective cohorts from Peking Union Medical College Hospital (2018–2024) were analyzed. In the NGS cohort (n = 1,343), HER2-amplified cases were identified based on NGS-derived gene copy number (GCN), and their clinicopathological and molecular features were characterized using stage-matched HER2-non-amplified controls. In the IHC cohort (n = 3,585), spatial HER2 expression heterogeneity was comprehensively assessed. Finally, treatment outcomes were reviewed in four HER2-amplified patients who received anti-HER2 therapy. HER2 amplification was detected in 2.53

C-Myc overexpression is an important molecular hallmark of pancreatic ductal adenocarcinoma (PDAC), but directly targeting c-Myc is extremely challenging. Identifying key upstream factors involved in c-Myc overexpression provides promising indirect targets for c-Myc. Public transcriptomic and clinical datasets, including TCGA, GEO, were integrated to identify c-Myc-associated long noncoding RNAs in PDAC, with LINC01963 selected for further investigation. The functional roles of LINC01963 were validated using human PDAC cell lines and in vivo proliferation models. The molecular mechanisms underlying c-Myc regulation by LINC01963 were explored using RNA pull-down, RIP-seq, RIP-qPCR, Co-IP, mass spectrometry, ubiquitination assays, truncation and site-directed mutagenesis analyses, and dual-luciferase reporter assays. Survival associations were evaluated using Kaplan–Meier analysis and Cox proportional hazards regression. Here, the long noncoding RNAs (lncRNAs) highly expressed in PDAC and significantly correlated with c-Myc expression were identified using RNA sequencing datasets. Among them, LINC01963 was found to interact with c-Myc, as confirmed by RNA pull-down and RIP-qPCR assays. Furthermore, high LINC01963 expression was correlated with poor PDAC prognosis, and functional studies demonstrated that its knockdown inhibited PDAC cell proliferation and xenograft tumor growth. Mechanistic studies identified LINC01963 as a key regulator of c-Myc stability, consequently affecting cell cycle through the c-Myc/p21-related signaling pathways. Further investigation revealed that LINC01963 enhanced N6-methyladenosine (m⁶A) modification of c-Myc mRNA by protecting methyltransferase-like 3 (METTL3) protein from KDM1B-mediated K48-linked ubiquitination and proteasomal degradation. Intriguingly, LINC01963 also stabilized c-Myc mRNA by facilitating the formation of a ternary complex with insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) and m⁶A-modified c-Myc. Our study reveals that LINC01963 promotes PDAC tumorigenesis through METTL3/IGF2BP2 axis-coordinated regulation of c-Myc, suggesting a new strategy for indirectly targeting c-Myc.

Dysregulated FGFR4 signaling has been associated with aggressive subtypes of breast cancers, characterized by HER2 enrichment or endocrine resistance. However, the biological functions of FGFR4 across breast cancer subtypes remain unclear. This study investigated the molecular characteristics of FGFR4-high tumors to inform potential therapeutic strategies. This study analyzed clinicopathological characteristics and gene expression profile of 53 hormone receptor-positive (HR+) and 41 HR-negative (HR−) patients using the AmoyDx Master Panel. The results were validated using The Cancer Genome Atlas (TCGA) and single-cell RNA-seq datasets. The patients in the PUMCH cohort (n = 94) were stratified by HER2 and HR statuses and further stratified according to FGFR4 expression. FGFR4-high tumors showed no genomic differences but enriched immune activation pathways, specifically in HR+HER2-low/positive subgroups. HR+ tumors with co-expression of FGFR4 and HER2 exhibited increased immune infiltration (T cells, NK cells, M1 macrophages) and upregulated checkpoints (BTLA, CTLA4, HAVCR2, LAG3). Single-cell data confirmed elevated T-cell abundance in HR+HER2-high FGFR4-high cases. TCGA analysis linked high FGFR4 to prolonged disease-free survival (DFS) in HR+HER2-positive patients but reduced DFS in HR+HER2-zero patients. Co-expression of FGFR4 and HER2 is associated with a proinflammatory tumor microenvironment in HR+ breast cancer, suggesting immunotherapy potential. Further studies should explore therapeutic strategies to reshape the tumor immune microenvironment.

OBJECTIVES:Pediatric myelodysplastic syndromes (MDS) differ from adult MDS, and their genetic basis is poorly understood. This study characterizes the genomic features and clinical outcomes of advanced pediatric MDS. METHODS:In this retrospective study, next-generation sequencing was performed on 63 pediatric patients with advanced MDS, including 46 with MDS with excess blasts (MDS-EB) and 17 with MDS-EB in transformation (MDS-EB-T, 2016 WHO classification), to detect somatic and potential germline variants. RESULTS:Mutations in 53 genes were detected in 49 patients (77.8%), with a median of 2 variants per patient (range, 0-8). Alterations in the RAS/MAPK pathway were most common, occurring in 28 patients (44.4%). Monosomy 7 significantly co-occurred with SETBP1, ETV6, and GATA2 mutations (p < 0.01). Time-dependent analyses showed HSCT improved 2-year overall survival (OS, 42.6% vs. 84.5%, p = 0.003) and event-free survival (EFS, 37.3% vs. 58.2%, p = 0.011). In multivariate analyses, HSCT was strongly associated with improved OS and EFS (p < 0.01). PTPN11 mutation remained an independent predictor of poorer OS and EFS (p < 0.05), and MDS-EB-T subtype independently predicted inferior EFS (p < 0.05). CONCLUSION:In advanced pediatric MDS, HSCT was associated with improved survival, whereas PTPN11 mutations emerged as an adverse prognostic factor.

Background:Multifocal (MF) and multicentric (MC) breast cancers (MMBC) refer to the presence of more than two synchronous ipsilateral breast carcinomas. MMBC with more than 2 foci is a relatively rare case, and the heterogeneity among different foci requires a comprehensive consideration for its surgical strategy and other treatment. Case Description:The patient was a 38-year-old woman who accidentally discovered self-palpable masses in the upper quadrant breast. Preoperative mammography showed atypical results, and ultrasound and breast dynamic contrast-enhanced magnetic resonance imaging supplemented the evaluation. Considering her condition of more than ten potential foci, relatively small breast and the patient's request, the mastectomy surgical strategy was chosen for the cosmetic outcome. The pathological analyses and immunochemical staining demonstrated similarity between different foci, and the postoperative treatment was made according to a comprehensive consideration among lesions. Conclusions:Early and accurate diagnosis of MMBC is critical, and more accurate preoperative diagnosis relies on breast magnetic resonance imaging beyond ultrasound and mammography. In this case of multiple lesions, extensive lesions, multi-center lesions and small breasts, mastectomy is first under consideration, while the false positivity from imaging evaluation requires attention. The heterogeneity among foci in MMBC cannot be overlooked and necessitates a comprehensive understanding for guiding surgical and other therapeutic interventions.

Background Human epidermal growth factor receptor 2 (HER2) is an emerging therapeutic target in endometrial carcinoma (EC). Current guidelines recommend routine HER2 testing for p53 abnormal (p53abn) tumors, potentially underestimating its value in non-p53abn cases. This study aimed to assess the incidence and clinical relevance of HER2 immunoreactivity in advanced non-p53abn EC. Methods HER2 immunohistochemistry and next-generation sequencing were performed in 128 advanced EC patients. Clinicopathological features, survival, and molecular alterations were compared according to HER2 immunoreactivity. Results Of all patients, 18.8% were HER2 2+/3+, 28.9% were HER2 1+, and 52.3% were HER2 0. Molecular classification included 1.6% POLE mutant, 35.2% mismatch repair-deficient/ microsatellite instability-high, 29.7% p53abn, and 33.6% no specific molecular profile (NSMP). In the non-p53abn group, HER2 3+ was less frequent than in the p53abn group, whereas the frequencies of HER2 2+ and 1+ did not differ significantly between the two groups. In non-p53abn patients, HER2 2+/3+ occurred most frequently in clear cell carcinoma (CCC, 6/11, 54.5%) and was associated with adnexal metastasis (2+/3+ vs. 1+, 66.7% vs. 15.4%, P<0.05). No survival differences were observed among non-p53abn patients by HER2 immunoreactivity, however, within the NSMP subgroup, both overall and progression-free survival were worse in HER2 2+/3+ compared with 1+ (log-rank P<0.05). In non-p53abn ECs, KRAS mutations were significantly less frequent in HER2 2+/3+ group (2+/3+ vs. 1+, 6.7% vs. 46.2%, P<0.05). Conclusions HER2 2+/3+ immunoreactivity was detected in 16.7% of advanced non-p53abn EC, particularly enriched in CCC. These findings highlight the potential clinical significance of HER2 testing in non-p53abn patients.

OBJECTIVES:To investigate the genomic characteristics and prognostic factors of juvenile myelomonocytic leukemia (JMML) with RAS mutations. METHODS:A retrospective analysis was conducted on the clinical data of JMML children with RAS mutations treated at the Hematology Hospital of Chinese Academy of Medical Sciences, from January 2008 to November 2022. RESULTS:A total of 34 children were included, with 17 cases (50%) having isolated NRAS mutations, 9 cases (27%) having isolated KRAS mutations, and 8 cases (24%) having compound mutations. Compared to children with isolated NRAS mutations, those with NRAS compound mutations showed statistically significant differences in age at onset, platelet count, and fetal hemoglobin proportion (P<0.05). Cox proportional hazards regression model analysis revealed that hematopoietic stem cell transplantation (HSCT) and hepatomegaly (≥2 cm below the costal margin) were factors affecting the survival rate of JMML children with RAS mutations (P<0.05); hepatomegaly was a factor affecting survival in the non-HSCT group (P<0.05). CONCLUSIONS:Children with NRAS compound mutations have a later onset age compared to those with isolated NRAS mutations. At initial diagnosis, children with NRAS compound mutations have poorer peripheral platelet and fetal hemoglobin levels than those with isolated NRAS mutations. Liver size at initial diagnosis is related to the prognosis of JMML children with RAS mutations. HSCT can improve the prognosis of JMML children with RAS mutations.

INTRODUCTION:Mucinous adenocarcinoma is a special subtype of non-small cell lung carcinoma (NSCLC). Currently, it remains unclear whether the molecular alterations are associated with its clinicopathological characteristics. METHODS:A total of 93 cases of pulmonary mucinous adenocarcinoma were assessed in this study. DNA and RNA sequencing were performed and clinical pathological characteristics were collected. Correlation analyses were conducted to explore associations between molecular alterations, pathological features, and clinical outcomes. RESULTS:The KRAS mutation frequency was 49 %. The group with KRAS mutations had low to intermediate nuclear grade (p < 0.001), microscopic skip lesions (p = 0.005), and a lower proportion of patients with vascular invasion (p = 0.030). While vascular invasion (p = 0.044), intermediate to high nuclear grade, especially high nuclear grade (p = 0.007), and tumors with a maximum diameter greater than 4 cm (p = 0.012) were commonly observed in patients with TP53 mutations, which also was correlated with a shorter time to progression (TTP). CONCLUSIONS:In this study, we found that mucinous adenocarcinomas of the lung with KRAS mutations tended to be pure-type mucinous adenocarcinomas with low to intermediate-grade nuclei, microscopic skip lesions, and the absence of vascular invasion. Tumors with TP53 mutations tended to be larger in size and exhibit higher nuclear grade as well as frequent vascular invasion. These morphological features may suggest that the tumor is accompanied by some kind of molecular alteration. If this is found in the puncture biopsy specimen, the patient may be advised to undergo molecular testing with a view to finding a suitable targeted agent for treatment.

Cellular senescence serves as a critical tumor-suppressive mechanism across various cancer types, yet its role in FLT3-ITD-positive acute myeloid leukemia (AML) remains poorly understood. Through the analysis of multiple sequencing datasets, we identified that FLT3-ITD-positive patients with low p16INK4a expression have significantly worse prognoses. Consistent with these clinical findings, knockout of p16INK4a in mice was shown to accelerate FLT3-ITD AML onset. Mechanistic investigations further revealed that the FLT3-ITD mutation suppresses p16INK4a expression via the STAT5A-E2F3-EZH2 signaling axis. This downregulation of p16INK4a allows cells to evade senescence, thereby promoting increased malignancy and establishing a positive feedback loop that exacerbates disease progression. This mechanism provides a molecular explanation for the poorer long-term survival observed in this patient subset. Furthermore, the FLT3-ITD-STAT5A/E2F3/EZH2-p16INK4a axis identified in this study represents a promising therapeutic target for addressing refractory FLT3-ITD AML with low p16INK4a expression.

Asparaginase is a cornerstone of pediatric acute lymphoblastic leukemia (ALL) therapy, but treatment discontinuation due to toxicity may increase relapse risk and compromise outcomes. We retrospectively analyzed 993 pediatric ALL patients (aged 1.0–17.9 years) treated under the CCCG-ALL-2015 protocol from May 2015 to October 2020. Patients were followed from the last administered asparaginase dose until relapse, death, secondary malignancy (SMN), or end of follow-up (median: 6.0 years). Asparaginase was truncated in 40 (4.0

Background: Tyrosine kinase inhibitors (TKIs) have transformed the prognosis of chronic myeloid leukemia (CML), but pediatric patients face unique challenges due to prolonged exposure. Early molecular response (EMR, BCR::ABL1 ≤ 10% at 3 months) is a recognized predictor of favorable outcomes in adults and has been correlated with improved responses in children. However, its relationship with achieving deep molecular remission (DMR, BCR::ABL1 ≤ 0.01%) in pediatric CML remains unclear. Methods: We performed a single-center, retrospective analysis of 103 pediatric patients with chronic-phase CML treated with frontline TKIs. Among them, 88 were evaluable for molecular response. BCR::ABL1 transcript levels were quantified by real-time quantitative PCR on the International Scale, and molecular responses were assessed. Associations between early molecular dynamics and long-term outcomes were evaluated using Kaplan–Meier and cumulative incidence analyses. Results: At 3 months, 64.8% achieved EMR. Early responders had significantly higher MMR rates at 12 months (80.8% vs. 5.6%; p = 0.00018) and DMR at 24 months (70.4% vs. 42.2%; p = 0.029). The ≥0.45-log reduction in BCR::ABL1 transcripts at 3 months predicted shorter times to MMR (median 11 vs. 29 months) and DMR (18 vs. 50 months), as well as higher overall MMR (p = 0.011) and DMR (p = 0.014) incidences. Bone marrow fibrosis correlated with inferior molecular outcomes (p = 0.017 for MMR). Conclusions: Early BCR::ABL1 decline kinetics independently predict molecular depth in pediatric CML. Quantitative early transcript reduction may guide risk-adapted management and optimize long-term TKI strategies in children.

Abstract Background Chronic myeloid leukemia (CML) is extremely rare in pediatric populations, and clinical features and therapeutic responses in children differ significantly from those observed in adults. This study aimed to analyze the characteristics of molecular response and associated influencing factors in pediatric patients with chronic-phase CML treated with tyrosine kinase inhibitors (TKIs). Methods This retrospective study enrolled pediatric patients newly diagnosed with chronic-phase CML who received TKI treatment. Inclusion criteria were as follows: age at diagnosis less than 18 years, and diagnosis consistent with European LeukemiaNet (ELN) criteria. Patients with an interval greater than 6 months between diagnosis and initiation of TKI therapy or those lacking critical clinical data were excluded. Results From July 2007 to February 2025, a total of 88 pediatric patients younger than 18 years with chronic-phase CML were included. Among them, 73% were male, and the median age at diagnosis was 9.2 years (range: 1.0–17.0 years). The most common clinical presentations at diagnosis were fever (32%), asymptomatic disease (28%), and fatigue (27%). The median white blood cell (WBC) count at diagnosis was 156.8×109/L (range: 23.9–709.6×109/L). Splenomegaly was observed in 69% of the patients, with a median spleen size of 9.0 cm below the costal margin (range: 1.0–25.3 cm). According to the Eutos Long Term Survival (ELTS) score, 63% of patients were classified as low risk, 17% as intermediate risk, and three patients as high risk. Additional chromosomal abnormalities (ACAs) were detected in five patients. With a median follow-up duration of 56.5 months (range: 4–215 months), 95% of patients achieved complete hematologic remission (CHR) within 3 months of treatment initiation. By the last follow-up, 20 patients experienced treatment failure, including loss of major molecular response (MMR) in 8 patients, disease progression to blast crisis in 3 patients, and 7 patients were lost to follow-up. Imatinib was administered as first-line therapy in 86 patients (97.7%), and 25 patients required second-line or subsequent TKI therapy. The 5-year overall survival (OS), event-free survival (EFS), failure-free survival (FFS), and progression-free survival (PFS) rates were 100.0%, 63.1%, 71.0%, and 95.9%, respectively. The cumulative incidence rates at 5 years for achieving complete cytogenetic response (CCyR), MMR, MR4, and MR5 were 88.9%, 87.3%, 74.8%, and 71.0%, respectively. Median time to achieve CCyR, MMR, MR4, and MR5 were 6, 12, 20, and 22 months, respectively. Among 61 patients who achieved MMR, 44 subsequently reached deep molecular response (DMR). Median interval from MMR to DMR was 5 months (95% CI: 3–9). Patients stratified by BCR-ABL reduction at 3 months (cutoff at 10-1.6 baseline) showed significantly shorter median times to MMR (6 vs. 14 months, p=0.0002) and DMR (11 vs. 20 months, p=0.016) in rapid-decline versus slow-decline groups, respectively. The 5-year FFS rate was higher in ELTS low-risk patients (78.1%, 95% CI: 66.4–91.9%) compared to intermediate/high-risk patients (53.6%, 95% CI: 31.9–90.1%; p=0.095), and the 5-year EFS showed a similar trend (low risk: 71.3%, 95% CI: 57.8–88.0%; intermediate/high risk: 53.6%, 95% CI: 31.9–90.1%; p=0.23). Of the 61 patients undergoing bone marrow biopsy, 30 had varying degrees of marrow fibrosis (grade 1: n=23, grade 2: n=6, grade 3: n=1). Patients with marrow fibrosis had significantly lower cumulative rates of MMR at 12 months compared to those without fibrosis (48.0% vs. 55.9%, p=0.026). Conclusions This study demonstrates favorable long-term outcomes in pediatric chronic-phase CML patients receiving TKIs. A rapid reduction of BCR-ABL transcript levels (below 10-1.6 of baseline) at 3 months significantly predicts earlier achievement of both MMR and DMR. Additionally, marrow fibrosis identified at diagnosis emerges as a potential negative predictor for molecular response. These findings underscore the necessity of early molecular monitoring and individualized risk assessment to optimize therapeutic strategies in pediatric CML populations.

IntroductionPorcine Circovirus (PCV2) infection is prevalent in pig farming and causes significant economic losses. In recent years, the PCV2d subtype has become the most prevalent genotype worldwide, exhibiting higher virulence, leading to more severe viremia and organ damage. Therefore, studying the biological characteristics of the PCV2d subtype is of great significance.MethodsWe established a PCV2d infection model using BALB/c mice and employed single-cell RNA sequencing (scRNA-seq) to systematically analyze the transcriptome of 10 cell types in the lung tissues of infected mice. We developed a comprehensive marker gene catalog for these cell types.ResultsCompared to uninfected mice, PCV2d infection induced extensive viral replication and immunosuppressive responses in most cell types. Monocyte macrophages with high levels of viral replication, pro-inflammatory cytokines, and various cell population interactions occurring through CD40-CD40L and CXCL14-CXCR4 were identified. These cells predominantly mediate antigen presentation and processing pathways in vivo, contributing to PCV2d-driven inflammatory lung injury.DiscussionOur data uncovered a complex unique immune response scenario in the lung tissue of mice after PCV2d infection, deciphering the potential mechanisms underlying PCV2d-driven inflammatory responses in mice. Furthermore, this study provides a rich database for the molecular basis of different cell types' responses to PCV2d infection.