The purpose of this observational study is to investigate the structure and composition of germinal centers in individuals with chronic HBV infection. The primary questions it aims to address are:

What are the phenotypes, functions, and complexity of B cell clones of the immune cells within the germinal centers of chronic HBV-infected individuals? Do chronic HBV-infected individuals have ectopic germinal centers in the liver? This will be studied by collecting peripheral blood and discarded liver, lymph node, and tonsil tissues from chronic HBV patients undergoing lymph node surgery, hepatectomy, and tonsillectomy.

This study is a single-center, prospective, cross-sectional investigation. We plan to enroll 280 participants.By collecting discarded liver, spleen, tonsil, and lymph node tissues from chronic HBV-infected and HBsAg-negative patients postoperatively, the investigators aim to compare the phenotypic and functional differences of various immune cells in the germinal centers of these organs between the two groups. The investigators will also identify the HBV antigen specificity of B cell clones in different germinal centers. Additionally, the investigators will observe the structural, transcriptomic, and proteomic differences in germinal center tissues between the two groups to elucidate the impact of chronic HBV infection on germinal centers. During the study, no random or protocol-driven treatments will be administered to participants. If clinically appropriate, the treating physician will make decisions and select treatment plans based on individual circumstances.

Data Collection Procedures Since this is a single-center, prospective, cross-sectional study, no additional visits or laboratory analyses beyond routine clinical practice are required. Physicians will determine treatment plans in accordance with instructions and local guidelines. The investigators will review patients' medical histories and laboratory reports to determine eligibility based on inclusion and exclusion criteria. Patients must sign the most recent informed consent form (ICF) approved by the IRB/IEC before data collection. In line with routine clinical practice, surgeons will prioritize clinical needs when obtaining surgical specimens, and then collect discarded clinical samples for experimental exploration and clinical data analysis. Each participant will be assigned a unique identification number, such as HBV-liver/tonsil/LN/spleen-1, HBV-liver/tonsil/LN/spleen-2, HC-liver/tonsil/LN/spleen-1, HC-liver/tonsil/LN/spleen-2, etc. All study documents (e.g., case report forms, clinical records) will use this identification number. In compliance with data privacy regulations, the use of unique identification numbers is permitted as long as they do not contain combinations of information that could identify participants (for example, the use of participants' initials and date of birth together is not allowed).

Sample Collection Demographic Data Recording: Record date of birth, gender, and initials. Medical History and Physical Examination: Include vital signs, height, weight, physical examination of all body systems; past and present medical history, including the presence of spider angiomas or palmar erythema, dull complexion, jaundice of skin and sclera, hepatic pain, and enlargement of liver, spleen, or lymph nodes.

Preoperative Peripheral Blood Collection: Draw 30 milliliters of peripheral blood from the subject's upper limb before surgery.

Collection of Discarded Liver , Spleen ,Tonsil, Lymph Node Tissue During Surgery: From subjects undergoing hepatectomy, tonsillectomy, splenectomy, or lymph node dissection, collect discarded liver, spleen ,tonsil, lymph node tissue during the surgical procedure.

Safety Monitoring, Reporting, and Medical Management Adverse Event (AE) Definition: An adverse event is any unfavorable medical occurrence in a patient or subject after the administration of a drug, whether or not considered related to the treatment. Adverse events can include any adverse signs (including abnormal laboratory findings), symptoms, or diseases temporally related to the use of the study drug, regardless of whether a causal relationship with the study drug is considered. Adverse events include both serious adverse events (SAEs) and non-serious adverse events.

SAE Definition: An SAE is a medical event occurring during a clinical study that requires hospitalization or prolongation of hospital stay, results in disability, affects the ability to work, is life-threatening or fatal, or causes congenital anomalies. These medical events include:

Events leading to death; Life-threatening events (defined as events where the subject is at immediate risk of death at the time of the event); Events requiring hospitalization or prolongation of hospital stay; Events that may result in permanent or significant disability

Inclusion Criteria:

1. Male or female, patients with chronic hepatitis B and hepatitis B surface antigen negative patients with clinical diagnosis who need to undergo liver, spleen, tonsil or lymph node surgery.
2. Before performing any research-related steps, the patient understood the research process, signed the informed consent, and complied with the research requirements.
3. Patients diagnosed with chronic hepatitis B virus infection according to the "Guidelines for the Prevention and Treatment of Chronic Hepatitis B(2019 Version)" .

Exclusion Criteria:

1. Those concomitant HCV, HIV infection, alcoholic fatty liver disease, non-alcoholic fatty liver disease, and autoimmune liver disease , etc. were excluded.
2. Diseases of the immune system or coagulation system, such as hyperthyroidism, diabetes, thrombocytopenic purpura, etc., were excluded.
3. Exclude serious underlying diseases that affect the immune status of the body.
4. The investigator believes that there are other circumstances that are not suitable for inclusion.

The group of HBV patients who underwent liver, spleen, tonsil, and lymph node surgery and the group of HBV-negative patients who underwent liver, spleen, tonsil, and lymph node surgery