{"doi":"10.1038/s41375-022-01514-3","title":"Associations of history of vaccination and hospitalization due to infection with risk of monoclonal B-cell lymphocytosis","abstract":"Monoclonal B-cell lymphocytosis (MBL) is an asymptomatic condition defined by the presence of circulating clonal B-cells in peripheral blood with a similar immunophenotype to that of chronic lymphocytic leukemia (CLL) without clinical symptoms or signs of disease [ 1 ]. MBL is a precursor to CLL [ 2 , 3 ] and has been shown to be associated with risk of developing serious infection independent of progression to CLL [ 4 , 5 ]. Prior studies have suggested that common infections (e.g., pneumonia, herpes zoster, sinusitis) are associated with subsequent increased risk of CLL [ 6 , 7 ]. These studies infer that CLL patients may have a disturbed immune function prior to CLL diagnosis making the individuals more susceptible to infections. Infections may also have a role in the development of CLL, possibly through antigenic stimulation [ 8 , 9 ]. Interestingly, individuals with MBL also have an increased risk of subsequent infections [ 4 , 5 ], and some studies have suggested the clonal B-cell population may directly alter immune function [ 10 ]. Thus, it is currently unknown whether infection prior to developing CLL is due to infections being an inciting event to CLL, or if infections are strictly a consequence of having MBL. Little is known about the history of infections and risk of developing MBL. In a study of 72 individuals with MBL and 380 controls, Casabonne et. al. reported increased risk of MBL in individuals with a history of pneumonia [ 11 ]. This study also reported that prior pneumococcal and influenza vaccinations were associated with reduced risk of MBL [ 11 ]. Moreover, two prior studies reported that select vaccinations may reduce risk of CLL [ 12 , 13 ]. Here we evaluated prior history of serious infections and prior history of vaccinations with risk of MBL in a screening cohort of 1009 MBLs and 4419 known not to have MBL. This study was approved by the institutional review boards of Mayo Clinic and Olmsted Medical Center, and participants provided written informed consent. Study participants were from the Mayo Clinic Biobank, a large-scale bio-repository of adult patients recruited through mailed invitation prior to their visit in primary care-based clinics, which ascertains patients’ vaccination history regardless of when vaccinations were given [ 14 ]. Participants had stored peripheral blood mononuclear cells (PBMC) collected from 7/14/2009 to 12/31/2020 that were screened for MBL, were residents of Olmsted county (location of Mayo Clinic), Minnesota at the time of sample collection, were 40 years of age or older with no prior history of hematologic malignancy, and had at least five years of medical history in the community prior to screening. For medical abstraction, we utilized the Rochester Epidemiology Project (REP), which is a population-based medical records-linkage system with access to the complete (in-patient and out-patient) medical records from all medical facilities in Olmsted county [ 15 ]. Using the REP, we queried medical records as far back as 1995 for any recorded history of vaccinations (regardless of when vaccination was given). Serious infections were defined as an individual who was hospitalized with an infection. Using the REP, we identified and reviewed all hospitalizations in the five years prior to sample collection for infections, following our published approach [ 4 ]. The five-year time period was selected to ensure the same amount of time of medical history. The medical record abstractor collecting data was blinded to MBL status. Our MBL screening method has been previously published [ 5 ]. Briefly, PBMC’s were screened using an eight-color flow cytometry assay capable of detecting clonal B-cell events to the 0.005% level. Individuals with high-count MBL were those who had a percent clonal B-cell count ≥85% out of total B-cell count [ 3 , 16 ]. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) to evaluate the association of prior vaccination","journal":"Leukemia","year":2022,"id":284608,"datarank":0.29188652235829704,"base_score":1.9459101490553132,"endowment":1.9459101490553132,"self_citation_contribution":0.29188652235829704,"citation_network_contribution":0.0,"self_endowment_contribution":0.29188652235829704,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":6,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9647,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2022-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":300279,"name":"Sara J. Achenbach","orcid":null,"position":1,"is_corresponding":false},{"id":437794,"name":"Sameer A. Parikh","orcid":"0000-0002-3221-7314","position":2,"is_corresponding":false},{"id":404947,"name":"Geffen Kleinstern","orcid":"0000-0001-6148-0421","position":3,"is_corresponding":false},{"id":451445,"name":"Esteban Braggio","orcid":"0000-0003-3860-4830","position":4,"is_corresponding":false},{"id":304439,"name":"Aaron D. Norman","orcid":"0000-0002-4208-2708","position":5,"is_corresponding":false},{"id":420931,"name":"Kari G. Rabe","orcid":"0000-0002-7313-1875","position":6,"is_corresponding":false},{"id":328451,"name":"Celine M. Vachon","orcid":"0000-0002-1962-9322","position":7,"is_corresponding":false},{"id":490131,"name":"Connie Lesnick","orcid":"0009-0008-2812-1214","position":8,"is_corresponding":false},{"id":454796,"name":"Timothy G. Call","orcid":"0000-0002-8465-9587","position":9,"is_corresponding":false},{"id":70827,"name":"Janet E. Olson","orcid":"0000-0003-4944-7789","position":10,"is_corresponding":false},{"id":302818,"name":"James R. Cerhan","orcid":"0000-0002-7482-178X","position":11,"is_corresponding":false},{"id":451444,"name":"Neil E. Kay","orcid":"0000-0002-5951-5055","position":12,"is_corresponding":false},{"id":475101,"name":"Curtis A. Hanson","orcid":"0000-0003-1333-5355","position":13,"is_corresponding":false},{"id":285630,"name":"Tait D. Shanafelt","orcid":"0000-0002-7106-5202","position":14,"is_corresponding":false},{"id":264807,"name":"Susan L. Slager","orcid":"0000-0002-5173-4712","position":15,"is_corresponding":false},{"id":274802,"name":"Nicholas Boddicker","orcid":"0000-0002-6784-2072","position":0,"is_corresponding":true}],"reference_count":16,"raw_metadata":{"citation_network_status":"fetched"},"created_at":"2026-07-19T00:29:36.828109Z","pmid":"35169244","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}