Lymphotropic polyomavirus and Merkel cell polyomavirus in patients infected with HIV or hepatitis B or C virus.

Background: LPV and MCV emerge as recent additions to the Polyomaviridae family, capable of inducing important infections. Studies have suggested the presence of LPV in human populations, with potential involvement in central nervous system (CNS) diseases. Additionally, MCV, closely related to LPV, has been implicated in Merkel cell carcinoma (MCC). This study aimed to explore the prevalence of LPV and MCV in individuals with compromised immunity due to chronic viral infections. Methods: 340 specimens, including HIV PCR-positive, HBV PCR-positive, HCV PCR-positive, and HIV/HBV/HCV negative sera, underwent screening via PCR technique to identify LPV and MCV genomes. Subsequently, sequencing was employed to validate the viral identity. Results: Out of all specimens, MCV DNA was detected in 8.52 % of participants, with a significantly higher prevalence in HIV-positive individuals (26.4 %). LPV was detected in only one HIV-positive patient. No co-detection of MCV and LPV was observed. Phylogenetic analysis confirmed the genetic similarity of the detected MCV strains to known references, while the LPV sequence showed 99 % identity to the published sequences of LPV-K38. Conclusion: This research provides insights into the prevalence of LPV and MCV in individuals with chronic viral infections. The study highlights the potential association between MCV and immunocompromised states, emphasizing the need for comprehensive investigations to understand the epidemiology, transmission routes, and clinical implications of these polyomaviruses in human populations.

Development of a Recombinant Protein-Based Immunoassay for Detection of Antibodies Against Karolinska Institute and Washington University Polyomaviruses.

To develop polyomavirus VP1 recombinant protein-based immunoassay, the expression of two polyomavirus (Karolinska Institute Polyomavirus; KIPyV, and Washington University Polyomavirus; WUPyV) VP1s in insect cells was investigated using an improved baculovirus system (BacMagic). The reliability of the purified VP1 to serve as antigens in serological tests was confirmed by the establishment of an enzyme-linked immunosorbent assay (ELISA). Two panels of serum samples were used, with Panel I comprising 60 sera (20 KIPyV-positive, 20 WUPyV-positive, and 20 negative) and Panel II consisting of 134 sera with unknown status. The seroprevalence of KIPyV and WUPyV in the study population was determined to be 62% and 50%, respectively. Antibody-negative sera exhibited low reactivities in both ELISAs, whereas antibody-positive sera displayed high reactivity with median optical density values of 1.37 and 1.47 in the KIPyV and WUPyV ELISAs, respectively. The differences in seroreactivities between antibody positive and negative for each virus were statistically significant (p < 0.0001; with 95% confidence interval). The study suggests that seroconversion for KIPyV and WUPyV occurs in childhood, with KIPyV seropositivity reaching 70% and WUPyV seropositivity reaching 60% after the age of 5 years. Adult seroprevalence for polyomaviruses was high, with more than 64% and 51% of the adult population being seropositive for KIPyV and WUPyV, respectively. The constant prevalence of KIPyV and WUPyV antibody in the age groups suggested that this antibody persists for life. The fact that antibody titers were generally stable over time revealed a persistent infection of polyomaviruses in the human population. The insect cell-derived recombinant VP1-based ELISA has been demonstrated to be valuable as a serological assay, offering a valid, reliable, fast, nonlaborious, and economical procedure.

Evaluation of respiratory complications in patients with X-linked and autosomal recessive agammaglobulinemia.

BACKGROUND: Congenital agammaglobulinemia is the first primary immunodeficiency disorder characterized by a defect in B lymphocyte development and subsequently decreased immunoglobulin levels. These patients are prone to suffer from recurrent infections mostly involving the respiratory tract. In this study, we aimed to describe in detail respiratory tract complications as the most prominent clinical feature among agammaglobulinemic patients. METHODS: A total number of 115 patients were included. Demographic, clinical, and genetic data were collected from the patients' medical records. Among the available patients, pulmonary function tests (PFTs) and/or high-resolution computed tomography (HRCT) were performed. RESULTS: Respiratory tract complications (85.2%) especially pneumonia (62.6%) were the most prominent clinical features in our cohort. Among patients with abnormal PFT results (N = 19), a mixed respiratory pattern was observed in 36.8%. HRCT was carried out in 29 patients; Bhalla scoring-based evaluation of these patients indicated excellent (44.8%), followed by good (34.5%) and mild (20.7%) results. Bronchiectasis was found in 13 patients undergoing HRCT (44.8%). We found significant inverse correlations between the Bhalla score and incidence rate of pneumonia, as well as the presence of bronchiectasis. Patients with abnormal PFT results had statistically significant higher bronchiectasis frequency and lower Bhalla scores compared to those with normal results. Forty-one patients were deceased, and here, respiratory failure was the most common cause of death (45.5%). CONCLUSION: High prevalence of respiratory tract infections among agammaglobulinemic patients and subsequent progression to permanent lung damage highlights the importance of implementing respiratory evaluation as part of routine follow-up program of agammaglobulinemic patients. Physicians should be aware of this and regularly monitor the respiratory function of these patients to allow for timely diagnosis and treatment initiation aiming to improve patients' prognosis and quality of life.