Cytomegalovirus (CMV) infections acquired by very-low-birthweight (VLBW) infants are incompletely characterized. To examine CMV transmission in VLBW infants, we evaluated maternal DNAlactia, infant DNAemia, and presence of clinical disease in a blinded study in VLBW infants in our newborn intensive care unit (NICU). To examine these issues, 200 VLBW infants were enrolled in a surveillance study, with weekly breast milk and infant whole blood samples collected, as available. Virologic (breast milk and infant whole blood real time PCR) and immunologic (IgG, IgM, and IgG avidity) correlates were evaluated. A chart review examined whether infants had symptoms compatible with CMV disease. DNAlactia was identified in 65/150 (43%) of lactating mothers. Nine CMV infections were identified in 9/75 CMV-exposed infants (12% of exposed infants). A higher median breast milk viral load (DNAlactia) correlated with an increased likelihood of DNAemia (p = 0.05). Despite potential symptoms compatible with CMV infection, clinicians had not considered the diagnosis of CMV in 6/9 cases (66%). All of these infants had chronic lung disease at discharge. There was no correlation between IgG antibody titer or IgG avidity index and the likelihood of transmission or CMV disease. In conclusion, in VLBW infants receiving milk from seropositive mothers, CMV infections are commonly acquired, and are frequently unrecognized. Future studies are needed to determine whether routine surveillance for CMV of either breast milk or infant plasma is beneficial in preventing or recognizing infection.
Development of a vaccine against congenital infection with human cytomegalovirus is complicated by the issue of re-infection, with subsequent vertical transmission, in women with pre-conception immunity to the virus. The study of experimental therapeutic prevention of re-infection would ideally be undertaken in a small animal model, such as the guinea pig cytomegalovirus (GPCMV) model, prior to human clinical trials. However, the ability to model re-infection in the GPCMV model has been limited by availability of only one strain of virus, the 22122 strain, isolated in 1957. In this report, we describe the isolation of a new GPCMV strain, the CIDMTR strain. This strain demonstrated morphological characteristics of a typical Herpesvirinae by electron microscopy. Illumina and PacBio sequencing demonstrated a genome of 232,778 nt. Novel open reading frames ORFs not found in reference strain 22122 included an additional MHC Class I homolog near the right genome terminus. The CIDMTR strain was capable of dissemination in immune compromised guinea pigs, and was found to be capable of congenital transmission in GPCMV-immune dams previously infected with salivary gland‑adapted strain 22122 virus. The availability of a new GPCMV strain should facilitate study of re-infection in this small animal model.
16 July 2022 in International Journal of Infectious Diseases
CMV viremia is associated with increased mortality in persons with HIV. We previously demonstrated that CMV viremia was a risk factor for 10-week mortality in antiretroviral therapy (ART)-naïve persons with cryptococcal meningitis. We investigated whether similar observations existed over a broader cohort of patients with HIV-associated meningitis at 18 weeks. We prospectively enrolled Ugandans with cryptococcal or TB meningitis into clinical trials in 2015–2019. We quantified CMV DNA concentrations from stored baseline plasma or serum samples from 340 participants. We compared 18-week survival between those with and without CMV viremia. We included 308 persons with cryptococcal meningitis and 32 with TB meningitis, of whom 121 (36%) had detectable CMV DNA. Baseline CD4+ T-cell counts (14 vs. 24 cells/μl; P = 0.07) and antiretroviral exposure (47% vs. 45%; P = 0.68) did not differ between persons with and without CMV viremia. The 18-week mortality was 50% (61/121) in those with CMV viremia versus 34% (74/219) in those without (P = 0.003). Detectable CMV viremia (adjusted hazard ratio [aHR] 1.60; 95% confidence interval [CI] 1.13–2.25; P = 0.008) and greater viral load (aHR 1.22 per log10 IU/ml increase; 95% CI 1.09–1.35; P <0.001) were positively associated with all-cause mortality through 18 weeks. CMV viremia at baseline was associated with a higher risk of death at 18 weeks among persons with HIV-associated cryptococcal or TB meningitis, and the risk increased as the CMV viral load increased. Further investigation is warranted to determine whether CMV is a modifiable risk contributing to deaths in HIV-associated meningitis or is a biomarker of immune dysfunction.
A universal screening research study was conducted in six hospitals to identify the clinical sensitivity of polymerase chain reaction (PCR) testing on newborn dried blood spots (DBSs) versus saliva specimens for the diagnosis of congenital cytomegalovirus (cCMV). CMV DNA positive results from DBSs or saliva were confirmed with urine testing. Findings of several false-positive (FP) saliva PCR results prompted an examination of a possible association with donor milk. Documentation of the frequency of positive saliva results, including both true-positive (TP) and FP status from clinical confirmation, occurred. The frequency of donor milk use was compared for TP and FP cases. Of 22,079 participants tested between 2016 and 2022, 96 had positive saliva results, 15 were determined to be FP, 79 TP, and 2 were excluded for incomplete clinical evaluation. Newborn donor milk use was identified for 18 (19.14%) of all the positive saliva screens. Among the 15 FPs, 11 (73.33%) consumed donor milk compared to 7 of the 79 TPs (8.8%) (OR 28.29, 95% CI 7.10–112.73, p < 0.001). While milk bank Holder pasteurization inactivates CMV infectivity, CMV DNA may still be detectable. Due to this possible association, screening programs that undertake testing saliva for CMV DNA may benefit from documenting donor milk use as a potential increased risk for FP results.
The transcription factor GLI1 (GLI family zinc finger 1) plays a key role in the development and progression of multiple malignancies. To date, regulation of transcriptional activity at target gene promoters is the only molecular event known to underlie the oncogenic function of GLI1. Here, we provide evidence that GLI1 controls chromatin accessibility at distal regulatory regions by modulating the recruitment of SMARCA2 (SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 2) to these elements. We demonstrate that SMARCA2 endogenously interacts with GLI1 and enhances its transcriptional activity. Mapping experiments indicated that the C-terminal transcriptional activation domain of GLI1 and SMARCA2's central domains, including its ATPase motif, are required for this interaction. Interestingly, similar to SMARCA2, GLI1 overexpression increased chromatin accessibility, as indicated by results of the micrococcal nuclease assay. Further, results of assays for transposase-accessible chromatin with sequencing (ATAC-seq) after GLI1 knockdown supported these findings, revealing that GLI1 regulates chromatin accessibility at several regions distal to gene promoters. Integrated RNA-seq and ATAC-seq data analyses identified a subset of differentially expressed genes located in cis to these regulated chromatin sites. Finally, using the GLI1-regulated gene HHIP (Hedgehog-interacting protein) as a model, we demonstrate that GLI1 and SMARCA2 co-occupy a distal chromatin peak and that SMARCA2 recruitment to this HHIP putative enhancer requires intact GLI1. These findings provide insights into how GLI1 controls gene expression in cancer cells and may inform approaches targeting this oncogenic transcription factor to manage malignancies.