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Summary: We characterized Mycobacterium bovis BCG isolates found in lung and brain samples from a previously vaccinated patient with IFNγR1 deficiency. The isolates collected displayed distinct genomic and phenotypic features consistent with host adaptation and associated changes in antibiotic susceptibility and virulence traits. Background: We report a case of a patient with partial recessive IFNγR1 deficiency who developed disseminated BCG infection after neonatal vaccination (BCG-vaccine). Distinct M. bovis BCG-vaccine derived clinical strains were recovered from the patient’s lungs and brain. Methods: BCG strains were phenotypically (growth, antibiotic susceptibility, lipid) and genetically (whole genome sequencing) characterized. Mycobacteria cell infection models were used to assess apoptosis, necrosis, cytokine release, autophagy, and JAK-STAT signaling. Results: Clinical isolates BCG-brain and BCG-lung showed distinct Rv0667 rpoB mutations conferring high- and low-level rifampin resistance; the latter displayed clofazimine resistance through Rv0678 gene (MarR-like transcriptional regulator) mutations. BCG-brain and BCG-lung showed mutations in fadA2, fadE5, and mymA operon genes, respectively. Lipid profiles revealed reduced levels of PDIM in BCG-brain and BCG-lung and increased TAGs and Mycolic acid components in BCG-lung, compared to parent BCG-vaccine. In vitro infected cells showed that the BCG-lung induced a higher cytokine release, necrosis, and cell-associated bacterial load effect when compared to BCG-brain; conversely, both strains inhibited apoptosis and altered JAK-STAT signaling. Conclusions: During a chronic-disseminated BCG infection, BCG strains can evolve independently at different sites likely due to particular microenvironment features leading to differential antibiotic resistance, virulence traits resulting in dissimilar responses in different host tissues.

Abstract Background Sjögren’s syndrome (SS) is an autoimmune disease characterized by immune attack on the salivary and lacrimal glands. Given the known cytokine activation and type I interferon gene expression signature found in SS, we hypothesized that anticytokine autoantibodies might be detectable by Luciferase immunoprecipitation systems in some SS patients and correlate with clinical symptoms. Results Luciferase immunoprecipitation systems was used to screen for serum anti-cytokine autoantibodies in 57 primary SS patients and 25 healthy volunteers. Autoantibodies were detected against GMCSF, interferon-γ, -α and, -ω in one, two, two and six patients with SS, respectively. None of the healthy volunteers showed anticytokine autoantibodies and none of the SS or control subjects showed autoantibodies against interferon-λ. One 51-year old female SS subject with the highest anti-interferon-α and -ω autoantibody levels had stable autoantibody levels over the course of a year. In vitro functional testing of serum autoantibodies from this subject demonstrated partially neutralizing activity for interferon-α signaling. Clinical information on this individual revealed a low focus score and high levels of unstimulated salivary flow, suggesting the possibility that interferon-α autoantibody neutralizing activity may have contributed to the milder sicca symptoms. Conclusion Overall, these findings demonstrate that a subset of SS patients (16%) harbor autoantibodies against GMCSF, interferon-γ, interferon-ω, and interferon-α. These data support the observation that high levels of interferon-α autoantibodies may attenuate disease symptoms in SS.

Ibrutinib is associated with bleeding-related adverse events of grade ≤2 in severity, and infrequently with grade ≥3 events. To investigate the mechanisms of bleeding and identify patients at risk, we prospectively assessed platelet function and coagulation factors in our investigator-initiated trial of single-agent ibrutinib for chronic lymphocytic leukemia. At a median follow-up of 24 months we recorded grade ≤2 bleeding-related adverse events in 55% of 85 patients. No grade ≥3 events occurred. Median time to event was 49 days. The cumulative incidence of an event plateaued by 6 months, suggesting that the risk of bleeding decreases with continued therapy. At baseline, von Willebrand factor and factor VIII levels were often high and normalized on treatment. Platelet function measured via the platelet function analyzer (PFA-100™) was impaired in 22 patients at baseline and in an additional 19 patients on ibrutinib (often transiently). Collagen and adenosine diphosphate induced platelet aggregation was tested using whole blood aggregometry. Compared to normal controls, response to both agonists was decreased in all patients with chronic lymphocytic leukemia, whether on ibrutinib or not. Compared to untreated chronic lymphocytic leukemia patients, response to collagen showed a mild further decrement on ibrutinib, while response to adenosine diphosphate improved. All parameters associated with a significantly increased risk of bleeding-related events were present at baseline, including prolonged epinephrine closure time (HR 2.74, P=0.012), lower levels of von Willebrand factor activity (HR 2.73, P=0.009) and factor VIII (HR 3.73, P=0.0004). In conclusion, both disease and treatment-related factors influence the risk of bleeding. Patients at greater risk for bleeding of grade ≤2 can be identified by clinical laboratory tests and counseled to avoid aspirin, non-steroidal anti-inflammatory drugs and fish oils. ClinicalTrials.gov identifier NCT01500733