Non-classical monocytes predict progression of carotid artery bifurcation intima-media thickness in HIV-infected individuals on stable antiretroviral therapy

BACKGROUND: Inflammation may contribute to cardiovascular disease (CVD) among antiretrovirally suppressed HIV-infected individuals. We assessed relationships of monocyte, CD8 T-cell activation and plasma biomarkers to changes in carotid artery intima-media thickness (CIMT). METHODS: Longitudinal study of HIV-infected subjects ≥ 40 years and on stable antiretroviral therapy (ART) ≥ 3 months. Peripheral blood mononuclear cells were immunophenotyped by multiparameteric flow cytometry to quantify classical (CD14(++)CD16(−)), intermediate (CD14(++)CD16(+)), non-classical (CD14(low/+)CD16(++)) and transitional (CD14+CD16−) monocyte subsets and activated (CD38(+)HLA-DR(+)) CD8(+) T-cells at baseline. Plasma biomarkers were assessed by multiplex Luminex assay. High resolution B-mode ultrasounds of right carotid arteries were obtained. Changes in CIMT over 2 years at the right common carotid artery (CIMT(CCA)) and right bifurcation (CIMT(BIF)) were outcome variables. RESULTS: We studied 50 subjects: 84% male, median age 49 (Q1, Q3; 46, 56) years, median CD4 count 461 (317, 578) cells/mm(3), and with HIV RNA≤50 copies/mL in 84%. Change in CIMT(BIF) correlated with log values of baseline absolute count of non-classical monocytes (r=0.37, p=0.020), and with MCP-1 (r=0.42, p=0.0024) and TNF-α (r=0.30, p=0.036) levels. In multivariable linear regression, only non-classical monocytes and MCP-1 predicted the change in CIMT(BIF), independent of Framingham Risk Score and baseline CIMT(BIF). No correlation was noted between CD8 T-cell activation and CIMT(BIF) change. Monocyte subsets, CD8 T-cell activation and biomarker concentrations were not correlated with changes in CIMT(CCA). CONCLUSIONS: Our findings highlight the role of non-classical monocytes and MCP-1 in the progression of CIMT(BIF) in HIV-infected individuals on stable ART independent of traditional cardio-metabolic risk factors

BTK and PLCG2 remain unmutated in one-third of patients with CLL relapsing on ibrutinib

Patients with chronic lymphocytic leukemia (CLL) progressing on ibrutinib constitute an unmet need. Though Bruton tyrosine kinase (BTK) and PLCG2 mutations are associated with ibrutinib resistance, their frequency and relevance to progression are not fully understood. In this multicenter retrospective observational study, we analyzed 98 patients with CLL on ibrutinib (49 relapsing after an initial response and 49 still responding after ≥1 year of continuous treatment) using a next-generation sequencing (NGS) panel (1% sensitivity) comprising 13 CLL-relevant genes including BTK and PLCG2. BTK hotspot mutations were validated by droplet digital polymerase chain reaction (ddPCR) (0.1% sensitivity). By integrating NGS and ddPCR results, 32 of 49 relapsing cases (65%) carried at least 1 hotspot BTK and/or PLCG2 mutation(s); in 6 of 32, BTK mutations were only detected by ddPCR (variant allele frequency [VAF] 0.1% to 1.2%). BTK/PLCG2 mutations were also identified in 6 of 49 responding patients (12%; 5/6 VAF <10%), of whom 2 progressed later. Among the relapsing patients, the BTK-mutated (BTKmut) group was enriched for EGR2 mutations, whereas BTK-wildtype (BTKwt) cases more frequently displayed BIRC3 and NFKBIE mutations. Using an extended capture-based panel, only BRAF and IKZF3 mutations showed a predominance in relapsing cases, who were enriched for del(8p) (n = 11; 3 BTKwt). Finally, no difference in TP53 mutation burden was observed between BTKmut and BTKwt relapsing cases, and ibrutinib treatment did not favor selection of TP53-aberrant clones. In conclusion, we show that BTK/PLCG2 mutations were absent in a substantial fraction (35%) of a real-world cohort failing ibrutinib, and propose additional mechanisms contributing to resistance