Discordance between ABC blood phenotype and genotype in a domestic short-haired cat.

An adult domestic short-haired feline leukemia virus-infected cat was referred for kidney failure and worsening anemia requiring transfusions. ABC blood typing was performed with an immunochromatographic strip assay at different occasions. Gel column systems were used for the major and minor crossmatching tests, and anti-A and anti-B titers were determined. No discrete A or B bands appeared on the immunochromatographic strips at any time point for the recipient cat. The recipient's plasma agglutinated RBCs from tested type A and B cats. The recipient's RBCs appeared compatible with plasma from 1 type A and 2 B donors, and incompatible with plasma from another type A cat. Genotyping of recipient blood revealed a single homozygous c.179G>T CMAH variant predicting a blood type B. These studies suggest an unusual weak type B or missing all ABC antigens. The latter resembles the exceedingly rare Bombay phenotype in the human ABO blood group system.

Immune Profiling Demonstrates a Common Immune Signature of Delayed Acquired Immunodeficiency in Patients With Various Etiologies of Severe Injury.

OBJECTIVES: The host response plays a central role in the pathophysiology of sepsis and severe injuries. So far, no study has comprehensively described the overtime changes of the injury-induced immune profile in a large cohort of critically ill patients with different etiologies. DESIGN: Prospective observational cohort study. SETTING: Adult ICU in a University Hospital in Lyon, France. PATIENTS: Three hundred fifty-three septic, trauma, and surgical patients and 175 healthy volunteers were included in the REAnimation Low Immune Status Marker study. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Extensive immune profiling was performed by assessing cellular phenotypes and functions, protein, and messenger RNA levels at days 1-2, 3-4, and 5-7 after inclusion using a panel of 30 standardized immune markers. Using this immunomonitoring panel, no specificity in the immune profile was observed among septic, trauma, and surgical patients. This common injury-induced immune response was characterized by an initial adaptive (i.e., physiologic) response engaging all constituents of the immune system (pro- and anti-inflammatory cytokine releases, and innate and adaptive immune responses) but not associated with increased risk of secondary infections. In contrary, the persistence in a subgroup of patients of profound immune alterations at the end of the first week after admission was associated with increased risk of secondary infections independently of exposure to invasive devices. The combined monitoring of markers of pro-/anti-inflammatory, innate, and adaptive immune responses allowed a better enrichment of patients with risk of secondary infections in the selected population. CONCLUSIONS: Using REAnimation Low Immune Status Marker immunomonitoring panel, we detected delayed injury-acquired immunodeficiency in a subgroup of severely injured patients independently of primary disease. Critically ill patients' immune status could be captured through the combined monitoring of a common panel of complementary markers of pro-/anti-inflammatory, innate, and adaptive immune responses. Such immune monitoring needs to be incorporated in larger study cohorts with more extensive immune surveillance to develop specific hypothesis allowing for identification of biological systems affecting altered immune function related to late infection in the setting of acute systemic injury.

Generation of anti-DC-SIGN monoclonal antibodies capable of blocking HIV-1 gp120 binding and reactive on formalin-fixed tissue.

DC-SIGN is a C-type lectin of recognized importance in immunology and in the pathogenicity human pathogens. Monoclonal antibodies directed against DC-SIGN have been generated, but their systemic characterization for interfering with binding of the HIV-1 glycoprotein 120 has often been omitted. Moreover, so far, no anti-DC-SIGN monoclonal antibody has been described that recognizes its antigen after formalin fixation and paraffin embedding. In this study, we have generated new anti-DC-SIGN monoclonal antibodies using HeLa cells stably expressing DC-SIGN as immunogen. We have obtained 11 hybridoma clones producing antibodies that recognized DC-SIGN on monocyte-derived dendritic cells and on dermal-type macrophages. Seven monoclonal antibodies displayed a capacity to interfere with DC-SIGN binding to HIV-1 gp120. One recognized DC-SIGN on formalin-fixed dendritic cells and macrophages. Using this antibody we have obtained specific labelling of DC-SIGN and colocalisation with the dermal macrophage marker CD163 on human skin. The described monoclonal anti-human DC-SIGN antibodies will be of use to the scientific community to address fundamental immunology issues, in particular concerning macrophages and dendritic cells, and help elucidate infection events of pathogen targeting DC-SIGN as recognition receptor.