Previous studies have shown that natural killer (NK) cell activity was suppressed in volunteer subjects exposed to ultraviolet radiation (UVR) from solarium lamps. The present studies were carried out to determine the spectrum of UVR responsible for suppression of NK activity and to develop in vitro methods to analyze the effectiveness of sunscreen agents in prevention of UVR-mediated suppression of NK activity and other aspects of immune function. UVR from a xenon arc lamp source was used to irradiate peripheral blood lymphocytes (PBL) in wells of tissue culture flasks, and transmission interference filters were used to eliminate UVR of particular wavelengths. The results indicated that UVR from this source inhibited NK activity of PBL in a dose-dependent manner with a 50% inhibitory dose of 5.5 mJ/cm2 when unfiltered and 29.6 mJ/cm2 when diluted through cellulose acetate, which gave a UV spectrum similar to that in solar radiation. Equivalent suppression of NK activity was mediated by UV-A (UVR > 315 nm) at dose levels of 4.2 J/cm2, which was approximately 140 times greater than the amount of UV-B (UVR < 315 nm) needed to suppress NK activity. Similar dose-response curves were seen for inhibition of mitogenic responses to phytohemagglutinin except that the latter appeared less sensitive than NK to inhibition by UV-A. These studies suggest that when the greater proportion of UV-A in solar radiation and its greater penetration into skin is taken into account, UV-A may have equivalent or greater direct immunosuppressive effects than UV-B.(ABSTRACT TRUNCATED AT 250 WORDS)
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http://dx.doi.org/10.1111/j.1751-1097.1993.tb02287.x | DOI Listing |
Proc Natl Acad Sci U S A
February 2025
State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou 510050, China.
Chromobox 2 (CBX2), a crucial component of the polycomb repressive complex (PRC), has been implicated in the development of various human cancers. However, its role in the regulation of tumor immunogenicity and immune evasion remains inadequately understood. In this study, we found that ablation of CBX2 led to tumor growth inhibition, activation of the tumor immune microenvironment, and enhanced therapeutic efficacy of anti-PD1 or adoptive T cell therapies by using murine syngeneic tumor models.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
February 2025
U.S. Military HIV Research Program, Center for Infectious Disease Research, Walter Reed Army Institute of Research, Silver Spring, MD 20910.
HIV-1 envelope broadly neutralizing antibodies represent a promising component of HIV-1 cure strategies. To evaluate the therapeutic efficacy of combination monoclonal antibodies (mAbs) in a rigorous nonhuman primate model, we tested different combinations of simian immunodeficiency virus (SIV) neutralizing mAbs in SIVmac251-infected rhesus macaques. Antiretroviral therapy-suppressed animals received anti-SIV mAbs targeting multiple Env epitopes spanning analytical treatment interruption (ATI) in 3 groups (n = 7 each): i) no mAb; ii) 4-mAb combination; and iii) 2-mAb combination.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
February 2025
Department of Biological Sciences, College of Liberal Arts and Sciences, Wayne State University, Detroit, MI 48202.
The mammalian Hippo kinases, MST1 and MST2, regulate organ development and suppress tumor formation by balancing cell proliferation and death. In macrophages, inflammasomes detect molecular patterns from invading pathogens or damaged host cells and trigger programmed cell death. In addition to lytic pyroptosis, the signatures associated with apoptosis are induced by inflammasome activation, but how the inflammasomes coordinate different cell death processes remains unclear.
View Article and Find Full Text PDFPLoS Pathog
January 2025
Department of Infectious Diseases, Shanghai Institute of Infectious Diseases and Biosecurity, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, National Medical Center for Infectious Diseases, Huashan Hospital, Fudan University, Shanghai, China.
Hepatitis B virus (HBV) X protein (HBx) is a key factor for regulating viral transcription and replication. We recently characterized homeobox protein MSX-1 (MSX1) as a host restriction factor that inhibits HBV gene expression and genome replication by directly binding to HBV enhancer II/core promoter (EnII/Cp) and suppressing its promoter and enhancer activities. Notably, HBx expression was observed to be repressed more drastically by MSX1 compared to other viral antigens.
View Article and Find Full Text PDFJ Am Soc Nephrol
January 2025
Selzman Institute for Kidney Health, Section of Nephrology, Department of Medicine, Baylor College of Medicine, Houston, Texas 77030.
Background: Arteriovenous (AV) fistulas are the preferred access for dialysis but have a high incidence of failure. This study aims to understand the crosstalk between skeletal muscle catabolism and AV fistula maturation failure.
Methods: Skeletal muscle metabolism and AV fistula maturation were evaluated in mice with chronic kidney disease (CKD).
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