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Essential epidemiologic and virologic parameters must be measured to provide evidence for policy/public health recommendations and mathematical modeling concerning novel influenza A/H1N1 virus (NIV) infections. Therefore, from April through August of 2009, the authors collected nasopharyngeal specimens and information on antiviral medication and symptoms from households with NIV infection on a daily basis in Germany. Specimens were analyzed quantitatively by using reverse transcriptase-polymerase chain reaction. In 36 households with 83 household contacts, 15 household contacts became laboratory-confirmed secondary cases of NIV. Among 47 contacts without antiviral prophylaxis, 12 became cases (secondary attack rate of 26%), and 1 (8%) of these was asymptomatic. The mean and median serial interval were 2.6 and 3 days, respectively (range: 1-3 days). On average, the authors detected viral RNA copies for 6.6 illness days (treated in time = 5.7 days, not treated in time = 7.1 days; P = 0.06), but they estimated that most patients cease to excrete viable virus by the fifth illness day. Shedding profiles were consistent with the number and severity of symptoms. Compared with other nasopharyngeal specimen types, nasal wash was the most sensitive. These results support the notion that epidemiologic and virologic characteristics of NIV are in many aspects similar to those of seasonal influenza. [ABSTRACT FROM AUTHOR]

Human MoAbs of IgM class were developed against three regions of the HIV-1 envelope. Uninfected donor lymphocytes were immunized in vitro with recombinant protein pB1. Four out of five antibodies were directed to different parts of the V3 region, which contains a major neutralizing site. Two out of these antibodies were directed to more than one amino acid sequence, indicating reactivity to discontinuous sites. Two of the human MoAbs inhibited viral spread between cells in tissue culture, interpreted as reactivities to conserved amino acid sequences exposed during viral maturation. No MoAb neutralized virus, which may be explained by the relatively low avidity of the antibodies. One MoAb was directed to a region containing amino acids participating in CD4 binding. This technique appears to allow formation of antibodies with fine specificities other than those obtained in infected hosts. [ABSTRACT FROM AUTHOR]

Activated T cells in the peripheral blood of patients with systemic lupus erythematosus (SLE) were determined using monoclonal antibodies against activation antigens. Elevated percentages of HLA-DR+ T cells were found in association with active disease. In contrast, we observed an increase in IL-2 receptor-bearing T cells in only six out of 16 patients with active disease. In vitro assays, like spontaneous proliferation, response to IL-2, production of IL-2, and immunoglobulin synthesis have shown that the different patterns of activation antigens arc related to different functional stages of T-cell activation. The possible therapeutic consequences are discussed. [ABSTRACT FROM AUTHOR]

The influence of combined photochemical treatment with a haematoporphyrin derivative and visible light on antigen-presenting cells was evaluated. Treatment of murine skin grafts with this procedure prolonged their subsequent survival on allogeneic recipients. The haematoporphyrin derivative and light decreased the ATPase activity of epidermal Langerhans cells in murine skin. When stimulator cells in a human allogeneic mixed leucocyte reaction were treated with the haematoporphyrin derivative and light, they lost their stimulatory capacity. It is proposed that the haematoporphyrin derivative and visible light interfere, on analogy with ultraviolet radiation, with the function of antigen-presenting cells. [ABSTRACT FROM AUTHOR]

In order to the elucidate mucosal immunity HIV-1 seropositive individuals, we investigated oral mucosa washings from 20 HIV-1 seropositive patients for the presence of Langerhans cells (LC) and HIV-1 antigen-positive cells, and compared the results with those obtained from 20 HIV-1 seronegative healthy individuals. Monoclonal antibodies directed against CD1a, HLA-DR, CD3, and p24 were used to identify LC, T cells and HIV-1 core-antigen repectively. In oral mucosa wasings form HIV-1 seropositive patients there was a significant reduction in the number of CD1a[sup+] cells as compared with the healthy subjects. HIV-1 antigen-positive cells were not detected. The reduction of LC in oral mucosa washings from HIV-1 seropositive patients is probably associated with HIV-1 infection. The frequent occurrence of oral mucosal disorders in HIV-1 infected patients may in part be caused by a reduced LC-number and/or function. [ABSTRACT FROM AUTHOR]

Today, MALDI-ToF MS is an established technique to characterize and identify pathogenic bacteria. The technique is increasingly applied by clinical microbiological laboratories that use commercially available complete solutions, including spectra databases covering clinically relevant bacteria. Such databases are validated for clinical, or research applications, but are often less comprehensive concerning highly pathogenic bacteria (HPB). To improve MALDI-ToF MS diagnostics of HPB we initiated a program to develop protocols for reliable and MALDI-compatible microbial inactivation and to acquire mass spectra thereof many years ago. As a result of this project, databases covering HPB, closely related bacteria, and bacteria of clinical relevance have been made publicly available on platforms such as ZENODO. This publication in detail describes the most recent version of this database. The dataset contains a total of 11,055 spectra from altogether 1,601 microbial strains and 264 species and is primarily intended to improve the diagnosis of HPB. We hope that our MALDI-ToF MS data may also be a valuable resource for developing machine learning-based bacterial identification and classification methods., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)