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SARS-CoV-2 causes a wide spectrum of clinical manifestations and significant mortality. Studies investigating underlying immune characteristics are needed to understand disease pathogenesis and inform vaccine design. In this study, we examined immune cell subsets in hospitalized and nonhospitalized individuals. In hospitalized patients, many adaptive and innate ^immune cells were decreased in frequency compared with those of healthy and convalescent individuals, with the exception of an increase in B lymphocytes. Our findings show increased frequencies of T cell activation markers (CD69, OX40, HLA- DR, and CD154) in hospitalized patients, with other T cell activation/exhaustion markers (PD-L1 and TIGIT) remaining elevated in hospitalized and nonhospitalized individuals. B cells had a similar pattern of activation/exhaustion, with increased frequency of CD69 and CD95 during hospitalization followed by an increase in PD1 frequencies in nonhospitalized individuals. Interestingly, many of these changes were found to increase over time in nonhospitalized longitudinal samples, suggesting a prolonged period of immune dysregulation after SARS-CoV-2 infection. Changes in T cell activation/exhaustion in nonhospitalized patients were found to positively correlate with age. Severely infected individuals had increased expression of activation and exhaustion markers. These data suggest a prolonged period of immune dysregulation after SARS-CoV-2 infection, highlighting the need for additional studies investigating immune dysregulation in convalescent individuals., Introduction Since the first reports in December 2019, coronavirus disease 2019 (COVID-19), caused by the novel virus SARS-CoV-2, has spread worldwide and caused enormous public health and economic impacts (1, [...]

* Retrorectal cyst hamartoma (RCH) is a rare benign cystic lesion located in the retrorectal space. Malignancy arising in such lesions is very uncommon. In this study, 2 cases of mucinous adenocarcinoma arising in RCH are presented. In one case, dysplastic epithelium lined the cyst wall, surrounding the area of carcinoma and suggesting a dysplasia-carcinoma progression in RCH. Adenocarcinoma and the dysplastic epithelium were strongly positive for p53 and Ki-67 and showed negative staining for p21 by immunohistochemistry. These findings are suggestive of a mutation in the p53 gene in the adenocarcinoma and in dysplastic epithelium lining the cysts, similar to the dysplasia-carcinoma sequence described for the development of colonic adenocarcinoma. (Arch Pathol Lab Med. 2001;125:1361-1364), Retrorectal cyst hamartoma (RCH), also commonly known as tailgut cyst, is a rare benign cystic lesion located in the retrorectal space and is believed to derive from persistence of embryologic [...]

HIV frequently escapes CD8 T cell responses, leading to the accumulation of viral adaptations. We recently demonstrated that during chronic HIV infection, adapted epitopes can promote maturation of dendritic cells (DCs) through direct CD8 T cell interactions and lead to enhanced HIV trans-infection of CD4 T cells. Here, we sought to determine the role of such adaptations following HIV MRKAd5 vaccination. We observed that vaccine-induced adapted epitope-specific CD8 T cells promoted higher levels of DC maturation than nonadapted ones and that these matured DCs significantly enhanced HIV trans-infection. These matured DCs were associated with higher levels of interleukin 5 (IL-5) and IL-13 and a lower level of CXCL5, which have been shown to impact DC maturation, as well as a lower level of CXCL16. Finally, we observed that vaccine recipients with high HLA-I-associated adaptation became HIV infected more quickly. Our results offer another possible mechanism for enhanced infection among MRKAd5 vaccinees. [ABSTRACT FROM AUTHOR]

Testing of paired midturbinate (MT) nasal and nasopharyngeal (NP) swabs, collected by trained personnel from 40 patients with coronavirus disease 2019 (COVID-19), showed that more NP (76/95 [80%]) than MT swabs tested positive (61/95 [64%]) (P =.02). Among samples collected a week after study enrollment, fewer MT than NP samples were positive (45% vs 76%; P =.001). [ABSTRACT FROM AUTHOR]

A subset of COVID-19 patients exhibit post-acute sequelae of COVID-19 (PASC), but little is known about the immune signatures associated with these syndromes. We investigated longitudinal peripheral blood samples in 50 individuals with previously confirmed SARS-CoV-2 infection, including 20 who experienced prolonged duration of COVID-19 symptoms (lasting more than 30 days; median = 74 days) compared with 30 who had symptom resolution within 20 days. Individuals with prolonged symptom duration maintained antigen-specific T cell response magnitudes to SARS-CoV-2 spike protein in CD4+ and circulating T follicular helper cell populations during late convalescence, while those without persistent symptoms demonstrated an expected decline. The prolonged group also displayed increased IgG avidity to SARS-CoV-2 spike protein. Significant correlations between symptom duration and both SARS-CoV-2-specific T cells and antibodies were observed. Activation and exhaustion markers were evaluated in multiple immune cell types, revealing few phenotypic differences between prolonged and recovered groups, suggesting that prolonged symptom duration is not due to persistent systemic inflammation. These findings demonstrate that SARS-CoV-2-specific immune responses are maintained in patients suffering from prolonged post-COVID-19 symptom duration in contrast to those with resolved symptoms and may suggest the persistence of viral antigens as an underlying etiology.