Revealing the evolution of the tumor immune microenvironment in follicular lymphoma patients progressing within 24 months using single-cell imaging mass cytometry

Background

Patients with follicular lymphoma (FL) who experience disease progression within 24 months (POD24) have inferior outcomes. The tumor immune microenvironment (TIME) plays a crucial role in pathogenesis and progression of follicular lymphoma (FL). However, TIME evolution during progression of disease within 24 months (POD24) is elusive.

Methods

Spatially resolved and single-cell image mass cytometry with a panel of 36 metal-tagged antibodies was used to quantitatively analyze the TIME structure in 13 paired FLs at diagnosis and POD24.

Results

Follicles and peri-follicular regions were well dissected in structure. Peri-follicular regions represented a barrier for immune infiltration into the follicles. More FL-cells in the peri-follicular regions suffered CD8⁺T cells attacks under simultaneous protection of regulatory T cells (Tregs) and/or macrophages compared with that in the follicles irrespective of POD24. During POD24, increased CD163⁻ macrophages with PD-1 ligand upregulation and decreased CD8⁺T cells with upregulated LAG-3 expression around FL-cells were observed in the follicles. Spatial analyses demonstrated that FL-cells interacted more intimately with macrophages than with Tregs and less with cytotoxic T cells in both peri-follicular regions and follicles during POD24. In comparison, macrophages also cooperated more frequently with Tregs to simultaneously hijack FL-cells, creating an enhanced immunosuppressive environment in both peri-follicular and follicular regions during POD24.

Conclusions

Peri-follicular regions function as a barrier by recruiting both CD8⁺T cells and immunosuppressive cells, protecting follicular FL-cells from immune attack at diagnosis or POD24. FL-cells reside in a more immune-compromised microenvironment and evade immune cell attacks during POD24. Novel immunotherapeutic approaches harnessing LAG-3, macrophages, and Tregs will be empowered to overcome poor outcomes in patients with FL POD24.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13045-022-01326-z.

Soluble Free, Soluble Conjugated, and Insoluble Bound Phenolics in Tomato Seeds and Their Radical Scavenging and Antiproliferative Activities

The soluble free, soluble conjugated, and insoluble bound phenolic compounds in tomato seeds were extracted and analyzed using ultra-high-performance liquid chromatography-high-resolution mass spectrometry. Total phenolic content (TPC) and free radical scavenging activities along with the antiproliferative effects against the human colorectal cancer cell line (HCT-116) were also examined for the soluble free, soluble conjugated, and insoluble bound phenolic fractions. 13, 7, and 10 compounds were tentatively identified in the soluble free, soluble conjugated, and insoluble bound phenolic fractions, respectively, including indole-3-acetic acid derivatives, flavonoids, phenolic acid, and tyramine-derived hydroxycinnamic acid amines. The insoluble bound phenolic fraction was observed to have a greater TPC value and stronger free radical scavenging activities against ABTS^•+, DPPH^•, and peroxyl radicals and a stronger inhibitory effect against HCT-116 cells compared with the soluble free and the soluble conjugated fractions. Soluble free and insoluble bound fractions significantly inhibited the proliferation of the HCT-116 cell line, and no antiproliferative effects were observed with the soluble conjugated fraction under the experimental conditions. The results may provide a foundation for future application of tomato seeds as nutraceuticals in dietary supplements and functional foods.

[Investigation of the occurrence of musculoskeletal disorders at shoulder, neck and elbow of digestive endoscopy operators]

Objective: To investigate the effect of endoscopic operation volume on musculoskeletal disorders (MSDs) of shoulder, neck and elbow. Methods: From December 2019 to March 2020, random sampling was used to select 200 gastroenterologists from hospitals at or above the municipal level in Sichuan Province as the research object. Gastroenterologists were divided into 108 eadoscop in the low operation group (The operation volume is less than 5 000 cases) and 92 eadoscop in the high operation group (The operation volume is more than 5 000 cases) according to the operation volume. MSDS was investigated by UCLA shoulder scoring system, Tanaka Jingjiu cervical spondylosis scale and improved An and Morrey elbow scoring system, and the chi-square test was used to compare the basic conditions of different body parts in the two groups. The basic condition of each part of the two groups was tested and compared. Results: Compared with the low operation group, the age and working years of the high operation group were longer, and the difference was statistically significant (P<0.001). The most painful part between the two groups was the shoulder, accounting for 25.9% (28/108) and 37.0% (34/92), respectively. Occasional shoulder pain was the most (41.9%, 26/62) and normal function was the most (32.3%, 20/62) ; The forward flexion angle exceeds 150° at most (40.3%, 25/62). Slight pain often occurred in the neck, accounting for 57.7% (15/26), the occasional impact of pain on the upper limbs accounted for 61.5% (16/26), and the impact on the fingers accounted for 53.8% (14/26) ; 65.0% (15/26) had mild disturbance to the sense of signs; Normal tendon reflex accounted for 88.5% (23/26) ; The influence of opponents was weakness, discomfort and no dysfunction, accounting for 53.8% (14/26) ; Endoscopists with normal muscle strength (2 points) and mild decline accounted for 50.0% (13/26) respectively, and there was no significant difference among the groups (P=0.234、1.000、1.000、0.050、0.680、0.539、0.431、0.239). The elbow score scale showed that mild loss accounted for 55.0% (11/20), mild instability accounted for 65% (13/20), and mild pain accounted for 55.0% (11/20) . Conclusion: MSDs is a health problem faced by endoscopists, and targeted preventive measures should be taken for its possible causes.

The effect of hydration and dehydration on the conformation, assembling behavior and photoluminescence of PBLG

Hydration and dehydration play crucial roles in hydrophobic effects (HEs) and are yet to be understood. Poly(γ-benzyl-L-glutamate) (PBLG) homopolymers in THF/water with various water contents were investigated. We discovered that PBLG was hydrated at low water contents and adopted a helical conformation. The chain became dehydrated with increasing water content, which converted the PBLG₁₀₀ helix to a PPII-helix. The variation in the conformation resulted in an alteration of the self-assembled morphologies from fibers to particles. For PBLG₁₂ with a shorter chain, the chain underwent an α-to-β transition in the conformation due to dehydration as the water content increased, and correspondingly the morphologies varied from tapes to helical ribbons, and eventually to toroids at a higher water content. We also observed that this α-to-β transition is accompanied by an increase in intensity of the fluorescence, which is attributed to the through-space-conjugation of tightly packed phenyl groups within the β-sheet. The discovered effect of hydration and dehydration on the PBLG chain conformation, self-assembling behavior and optical function is essential for the innovation of polypeptide materials and understanding of water-mediated biological systems.

AB0139 DEEP IMMUNE PHENOTYPING OF T LYMPHOCYTE SUBSETS IN SYSTEMIC SCLEROSIS PATHOPHYSIOLOGY AND FOLLOWING RESPONSE TO TARGETED CYTOTOXIC TREATMENT

Background

Abnormalities in T lymphocyte populations are associated with the pathogenesis of many autoimmune diseases, such as systemic sclerosis (SSc). Various studies report on the aberrations of different T cell cytotoxic (CTL) and helper (Th) subsets that appear to be linked with inflammatory and/or fibrotic manifestations of patients with SSc. Since T cells seem to play a pivotal role in the pathophysiology of SSc, targeting the pathogenic T cell subsets might be a promising therapeutic option.

Objectives

Here we set out to comprehensively compare T lymphocyte phenotypes between SSc patients and healthy donors. We further test the in-vitro efficacy of a combination of anti-CD3/CD7 immunotoxins (CD3/CD7-IT), that have been developed to eliminate activated CD4+ and CD8+ T cells, to study specific sensitivity of T-cell subpopulations to CD3/CD7-IT.

Methods

30 SSc patients and 15 age and sex matched healthy donors were included. Of these patients, lymphocyte populations were quantified by 17-parameter flow cytometry of peripheral blood mononuclear cells (PBMCs) to identify CD4+ T helper cells (Th1, Th2, Th17, T peripheral helper), CD8+ naïve, memory, effector CTLs and senescent/exhausted subsets. We next developed a cell killing assay to evaluate the effect of T cell depletion. To address this, patients’ (N=6) PBMCs were first activated for 24 hours in the presence of phytohemagglutinin, followed by CD3/CD7-IT addition for 48 hours. Subset-specific T cell depletion was assessed by using a combination of CellTiter-Glow luminescent cell viability assay and multi-parameter flow cytometric (FCM) quantification of CD3/CD7-IT-induced cell death.

Results

Frequencies of effector CD8+ CTLs,Th2 and T peripheral helper cells were elevated in SSc patients compared to healthy controls. Furthermore, SSc patients exhibited lower percentages of the anti-fibrotic Th1 subset. A striking expansion of the senescent CD4+CD28- and CD8+CD28- populations was noted in patients, while these subsets were barely detectable in healthy controls. In-vitro adittion of anti-T cell immunotoxins effectively depleted 50 % of patients’ CD8+ T cells (including the CD8 effector subset) and 62% of CD4+ T cells (including Th2 and T peripheral helper cells). No difference in cytolytic sensitivity between different T cell subsets was observed.

Conclusion

Our findings demonstrate that deep FCM immunephenotyping reveals pathophysiological differences in peripheral T cell subsets of SSc patients. Strikingly, the developed cytolytic assays show that CD3/CD7-IT is able to target the potential disease-associated T cell subsets in an in-vitro setting.

References

Not applicable

Disclosure of Interests

None declared

Discovery of Natural Rosin Derivatives Containing Oxime Ester Moieties as Potential Antifungal Agents to Control Tomato Gray Mold Caused by Botrytis cinerea

Inspired by the application of natural products against pathogenic fungi, two series of dehydroabietyl oxime ester derivatives were synthesized using rosin as a raw material. Based on the evaluation and screening of in vitro antifungal activities against Botrytis cinerea (B. cinerea), Sclerotinia sclerotiorum, Valsa mali, Rhizoctonia solani, Fusarium oxysporum, and Alternaria alternata, compound 4f exhibited the best antifungal activity against B. cinerea, and its EC₅₀ was 0.798 mg/L, which was lower than that of the positive control trifloxystrobin (1.112 mg/L). The in vivo antifungal activity results showed that 4f had satisfactory protective and curative effects on tomato. Physiological and biochemical studies showed that the action mechanism of compound 4f against B. cinerea is to change the morphology and the ultrastructure of the mycelium, increase the permeability of the cell membrane, and cause nucleus and mitochondrial dysfunction, thus leading to apoptosis. In addition, qualitative and quantitative structure-activity relationship studies showed that the inductive and conjugative interactions between compound 4f and the target receptor form an electron transfer process, thereby achieving an antifungal effect. These results indicated that compound 4f, which was derived from the natural product rosin, is a novel potential fungicidal candidate against B. cinerea.

Secretome of Mesenchymal Stem Cells from Consecutive Hypoxic Cultures Promotes Resolution of Lung Inflammation by Reprogramming Anti-Inflammatory Macrophages

The secretome from hypoxia-preconditioned mesenchymal stem cells (MSCs) has been shown to promote resolution of inflammation and alleviate acute lung injury (ALI) through its immunomodulatory function. However, the effects of consecutive hypoxic culture on immunomodulatory function of the MSCs secretome are largely unclarified. Here, we intend to investigate the effects of consecutive hypoxia on therapeutic efficacy of conditioned medium derived from MSCs (MSCs-CM) in alleviating ALI. Human umbilical cord-derived MSCs (UC-MSCs) were consecutively cultured in 21% O₂ (Nor-MSCs) or in 1% O₂ (Hypo-MSCs) from passage 0. Their conditioned medium (Nor-CM and Hypo-CM respectively) was collected and administered into ALI models. Our findings confirmed that Hypo-MSCs exhibited increased proliferation ability and decreased cell senescence compared with Nor-MSCs. Consecutive hypoxia promoted UC-MSCs to secrete immunomodulatory cytokines, such as insulin-like growth factor 1(IGF1), IL10, TNFα-stimulated gene 6(TSG6), TGFβ, and prostaglandin E2 (PGE2). Both Nor-CM and Hypo-CM could effectively limit lung inflammation, promote efferocytosis and modulate anti-inflammatory polarization of lung macrophages in ALI models. Moreover, the effects of Hypo-CM were more potent than Nor-CM. Taken together, our findings indicate that consecutive hypoxic cultures could not only promote both proliferation and quality of UC-MSCs, but also enhance the therapeutic efficacy of their secretome in mitigating lung inflammation by promoting efferocytosis and anti-inflammatory polarization of macrophages.

Resveratrol in Intestinal Health and Disease: Focusing on Intestinal Barrier

The integrity of intestinal barrier determines intestinal homeostasis, which could be affected by various factors, like physical, chemical, and biological stimuli. Therefore, it is of considerable interest and importance to maintain intestinal barrier function. Fortunately, many plant polyphenols, including resveratrol, could affect the health of intestinal barrier. Resveratrol has many biological functions, such as antioxidant, anti-inflammation, anti-tumor, and anti-cardiovascular diseases. Accumulating studies have shown that resveratrol affects intestinal tight junction, microbial composition, and inflammation. In this review, we summarize the effects of resveratrol on intestinal barriers as well as the potential mechanisms (e.g., inhibiting the growth of pathogenic bacteria and fungi, regulating the expression of tight junction proteins, and increasing anti-inflammatory T cells while reducing pro-inflammatory T cells), and highlight the applications of resveratrol in ameliorating various intestinal diseases.

[Cohort study on the association between hyperopia reserve and myopia incidence in primary school students: the Anyang Childhood Eye Study]

Objective: To analyze the longitudinal association between hyperopia reserve and the cumulative incidence of myopia in grade 1 primary school students. Methods: Cohort study. This study included 2 628 grade 1 primary school students (2 628 eyes) who without myopic at baseline from the Anyang Childhood Eye Study. There were 1 515 male and 1 113 female, aged(7.16±0.40) years. Every year, cycloplegic autorefraction was performed with 1% cyclopentolate eye drops to obtain data of hyperopia reserve. Students with different ranges of hyperopia reserve at baseline were analyzed. Axial length, anterior chamber depth, corneal curvature, lens thickness, and other parameters were obtained by ocular biometrics and compared by the independent sample ttest. Qualitative data were described by frequency and percentage, and comparison between groups was performed by the Chi-square test or exact probability method. Linear regression was used to analyze the association between baseline hyperopia reserve and spherical equivalent at 5 years. Results: The average hyperopia reserve was (+1.09±0.78) diopters (D) in grade 1 non-myopic children. Axial length, anterior chamber depth, corneal radius of curvature, and lens thickness were (22.66±0.72), (2.88±0.24), (7.80±0.25) and (3.62±0.19) mm, respectively. The cumulative incidence of myopia among non-myopic grade 1 primary school students was 8.5%, 21.5%, 35.6%, 47.6% and 64.1% at 1, 2, 3, 4 and 5 years, respectively. The incidence of myopia in girls was significantly higher than that in boys at 3, 4 and 5 years. The 5-year cumulative incidence of myopia was 4.6%, 26.3%, 52.3%, 78.6%, 92.6% and 94.3%, respectively, corresponding to students with baseline hyperopia reserve of >+2.00 D,+1.50 D to +2.00 D,+1.00 D to +1.50 D,+0.50 D to +1.00 D, 0.00 D to +0.50 D and -0.50 D to 0.00 D, and the difference was statistically significant (χ²=490.59, P<0.001). The regression equation between baseline hyperopia reserve and 5-year spherical equivalent was as follows: 5-year spherical equivalent =-3.135+1.692·baseline hyperopia reserve (R²=0.454, P<0.001). Conclusions: The lower the hyperopia reserve, the higher the incidence of myopia. Monitoring children's hyperopia reserve and early protection to reduce its consumption and timely detection of children at high risk of myopia are of great significance to prevent the occurrence and development of myopia.

[Spindle cell hemangioma: a clinicopathological and molecular analysis of eight cases]

Objective: To investigate the clinicopathological and genetic characteristics of spindle cell hemangioma (SCH). Methods: The clinical, morphological and immunohistochemical features of 8 SCHs diagnosed from January 2013 to September 2021 in West China Hospital, Sichuan University, Chengdu, China were retrospectively analyzed. Hotspot mutations for IDH1 codon 132 and IDH2 codon 172 were tested in 4 SCHs and 29 other non-SCH lesions using Sanger sequencing. Results: The 8 cases occurred in patients with a wide age range, from neonate to 46 years (mean 28 years, median 32 years). Both genders were equally affected. The course of the disease spanned from half a year to 31 years. Two SCHs were recurrent tumors. All tumors involved the distal extremities (4 of foot, 2 of ankle and 2 of hand). Six cases were presented as a single lesion and 2 cases as multiple lesions. The tumor diameters were 1-5 cm. All the 8 SCHs were typically composed of cavernous vascular space and solid components consisting of slit-like vessels, spindle cells and epithelioid endothelial cells which often exhibited cytoplasmic vacuolation. These two alternating components and the vacuolated epithelioid endothelial cells were the distinctive diagnostic clues for SCH. Vascular endothelial cells including epithelioid cells in the solid areas expressed CD31 (8/8), ERG (4/4), CD34 (5/8) and D2-40 (2/3). The spindle cells expressed SMA (8/8). Neither endothelial cells nor spindle cells expressed HHV8 (0/7), Desmin (0/5) or S-100 (0/3). Mutations were revealed in 2 SCHs, with IDH1 mutation (p.R132C) and IDH2 mutation (p.R172G), respectively. The IDH1/2 gene hotspot mutations were not found in the remaining 2 SCHs or the other 29 non-SCH lesions. Simple excisions were performed for 7 cases, and partial resection for 1 case. Follow-up information was obtained in 6 cases, with follow-up time ranging from 5 to 90 months (average, 46 months). No metastasis occurred in the 6 cases. No recurrence occurred in cases treated with simple excision. The residual lesions of the patient who received partial resection were stable. Conclusions: SCH is rare and should be differentiated from a variety of benign and malignant vascular lesions. An accurate diagnosis of SCH is clinically important and can be achieved by combining clinical information and typical pathological presentation. IDH1/2 gene hotspot mutations are specific to SCH in vascular lesions. Genetic detection is helpful in the diagnosis of challenging cases.

[Diagnostic value of MDM2 RNA in situ hybridization in atypical lipomatous tumor/well-differentiated liposarcoma and dedifferentiated liposarcoma]

Objective: To investigate the value of MDM2 RNA in situ hybridization (RNA-ISH) in diagnosing atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDL) and dedifferentiated liposarcoma (DDL). Methods: A total of 26 ALT/WDL/DDLs diagnosed from March 2017 to May 2019 in West China Hospital, Sichuan University, Chengdu, China and 18 control cases were included. MDM2 RNA-ISH was performed on all samples and compared with the fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) regarding their performance in detecting MDM2. Results: All samples were detected successfully using the three methods. Among 26 ALT/WDL/DDLs, all cases showed MDM2 amplification and positivity for MDM2 RNA-ISH (26/26, 100%). Twenty-four (24/26, 92.3%) of the 26 tested cases were positive for MDM2 IHC while two of them were negative. Eighteen control cases were all negative for MDM2 FISH and RNA-ISH, and 15 (15/18) cases were negative for MDM2 IHC. The sensitivity and specificity of RNA-ISH were both 100%, and those of MDM2 IHC were 92.3% and 83.3%, respectively. Diffuse staining was identified in all MDM2 RNA-ISH positive ALT/WDL/DDLs, but identified in only 8/24 (33.3%) of the MDM2 IHC positive cases. Among the 11 ALT/WDL/DDL samples evaluated on tissue microarray, the positive rate of MDM2 RNA-ISH was 100% with diffuse staining in all cases. The positive rate of MDM2 IHC was 9/11 while only 1 of the 9 cases showed diffuse staining. The result of MDM2 RNA-ISH was identical to that of MDM2 FISH and was overall consistent with that of MDM2 IHC (Kappa=0.763, P<0.001). Conclusions: In ALT/WDL/DDLs, results of MDM2 RNA-ISH are highly consistent with those of FISH. MDM2 RNA-ISH is more sensitive and more specific and has more diffuse positive signals than the IHC. The findings indicate that MDM2 RNA-ISH is highly valuable for the diagnosis and differential diagnosis of ALT/WDL/DDLs.

Use of real-time artificial intelligence in detection of abnormal image patterns in standard sonographic reference planes in screening for fetal intracranial malformations

OBJECTIVES

To develop and validate an artificial intelligence system, the Prenatal ultrasound diagnosis Artificial Intelligence Conduct System (PAICS), to detect different patterns of fetal intracranial abnormality in standard sonographic reference planes for screening for congenital central nervous system (CNS) malformations.

METHODS

Neurosonographic images from normal fetuses and fetuses with CNS malformations at 18-40 gestational weeks were retrieved from the databases of two tertiary hospitals in China and assigned randomly (ratio, 8:1:1) to training, fine-tuning and internal validation datasets to develop and evaluate the PAICS. The system was built based on a real-time convolutional neural network (CNN) algorithm, You Only Look Once, version 3 (YOLOv3). An image dataset from a third tertiary hospital was used to further validate, externally, the performance of the PAICS and to compare its performance with that of sonologists with different levels of expertise. Furthermore, a prospective video dataset was employed to evaluate the performance of the PAICS in a real-time scan scenario. The diagnostic accuracy, sensitivity, specificity and area under the receiver-operating-characteristics curve (AUC) were calculated to assess the performance of the PAICS and to compare this with the performance of sonologists with different levels of experience.

RESULTS

In total, 43 890 images from 16 297 pregnancies and 169 videos from 166 pregnancies were used to develop and validate the PAICS. The system achieved excellent performance in identifying 10 types of intracranial image pattern, with macro- and microaverage AUCs, respectively, of 0.933 (95% CI, 0.798-1.000) and 0.977 (95% CI, 0.970-0.985) for the internal validation image dataset, 0.902 (95% CI, 0.816-0.989) and 0.898 (95% CI, 0.885-0.911) for the external validation image dataset and 0.969 (95% CI, 0.886-1.000) and 0.981 (95% CI, 0.974-0.988) in the real-time scan setting. The performance of the PAICS was comparable to that of expert sonologists in terms of macro- and microaverage accuracy (P = 0.863 and P = 0.775, respectively), sensitivity (P = 0.883, P = 0.846) and AUC (P = 0.891, P = 0.788), but required significantly less time (0.025 s per image for PAICS vs 4.4 s for experts, P < 0.001).

CONCLUSIONS

Both in the image dataset and in the real-time scan setting, the PAICS achieved excellent diagnostic performance for various fetal CNS abnormalities. Its performance was comparable to that of experts, but it required less time. A CNN algorithm can be trained to detect fetal CNS abnormalities. The PAICS has the potential to be an effective and efficient tool in screening for fetal CNS malformations in clinical practice. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Methotrexate/mifepristone-combined with embryo removal in the treatment of caesarean scar pregnancy

OBJECTIVE

The aim of this study was to compare the effect of different administration modalities of methotrexate (MTX)/mifepristone in the initial medication stage, followed by embryo transfer in the treatment of caesarean scar pregnancy (CSP).

PATIENTS AND METHODS

A retrospective analysis of 66 CSP patients who received treatment in our hospital from January 2015 to July 2021 was performed, and participants were divided into three groups: Group one (n=14) received mifepristone followed by embryo removal treatment, Group two (n=29) received MTX followed by embryo removal, and Group three (n=23) received a methotrexate/mifepristone combined treatment followed by embryo removal. The basic findings were analysed, along with the curative effects between the three groups. Risk factors predicting additional treatment after initial intervention failure were analysed.

RESULTS

There were statistically significant differences in gestational age, hospitalization days, costs, myometrial thickness, cardiac activity, and mean sac diameter between groups (p<0.05) after grouping by eight weeks. The initial intervention success rates were 92.86%, 89.66%, and 65.22% in Group one, two, and three, respectively (p<0.05), while the complication rates were 14.29%, 6.90%, and 26.87%, respectively (p>0.05). After grouping according to eight weeks of gestational age, the difference in initial serum β-hCG between Group two and three was statistically significant (p<0.05). Mean sac diameter was a risk factor for additional treatment after initial intervention failure, with an odds ratio of 1.113 (p<0.05). A cut-off of 22.75 mm was a preferable indicator.

CONCLUSIONS

MTX/mifepristone followed by embryo removal is a reliable way to treat CSP. Mean sac diameter was a risk factor for additional treatment after initial intervention failure.

A Novel Chemical Binding Primer to Improve Dentin Bonding Durability

The dentin collagen matrix that is not completely enveloped by resin adhesive is vulnerable to degradation by intrinsic collagenases during the etch-and-rinse process, which contributes to the deterioration of the bonding interface. Current commercial adhesives have no functional components that can form covalent bonds to the dentin collagen matrix. In this study, a photocurable aldehyde, 4-formylphenyl acrylate (FA), was synthesized and for the first time applied as a primer in adhesive dentistry to covalently bind to collagen. Experimental groups with different concentrations of FA (1%, 3%, 5%, 7%, 9%) were prepared as primers. The cytotoxicity was evaluated by live/dead-cell staining and thiazolyl blue tetrazolium bromide assay. The interaction of FA with collagen was examined by attenuated total reflection Fourier transform infrared spectroscopy, hydroxyproline release under the degradation of type I collagenase, and thermogravimetric analysis. An optimal group was selected based on the degree of conversion of 2 universal adhesives and further divided depending on the treatment time (20 s, 30 s, 1 min, 2 min). The bonding performances were evaluated by microtensile strength before and after aging. Finally, the bonding interface was observed under confocal laser scanning microscopy and scanning electron microscope. The results indicated that FA demonstrated good biocompatibility, dentin modification capability, and infiltration. It not only effectively cross-linked dentin collagen to improve its stability against enzymatic hydrolysis and modify the adhesive interface but also potentially acted as a diluting monomer to induce deep penetration of adhesive resin monomers into the dentin. The bonding strength after aging was improved without jeopardizing the degree of conversion of 2 commercial adhesives. Such prominent advantages of using FA to improve the bonding performance promotes its further application in adhesive dentistry.