Lower hemoglobin levels in human immunodeficiency virus-infected patients with a positive direct antiglobulin test (DAT): relationship with DAT strength and clinical stages

Post-Immune Antibodies in HIV-1 Infection in the Context of Vaccine Development: A Variety of Biological Functions and Catalytic Activities

Unlike many other viruses, HIV-1 is highly variable. The structure of the viral envelope changes as the infection progresses and is one of the biggest obstacles in developing an HIV-1 vaccine. HIV-1 infection can cause the production of various natural autoantibodies, including catalytic antibodies hydrolyzing DNA, myelin basic protein, histones, HIV-integrase, HIV-reverse transcriptase, β-casein, serum albumin, and some other natural substrates. Currently, there are various directions for the development of HIV-1 vaccines: stimulation of the immune response on the mucous membranes; induction of cytotoxic T cells, which lyse infected cells and hold back HIV-infection; immunization with recombinant Env proteins or vectors encoding Env; mRNA-based vaccines and some others. However, despite many attempts to develop an HIV-1 vaccine, none have been successful. Here we review the entire spectrum of antibodies found in HIV-infected patients, including neutralizing antibodies specific to various viral epitopes, as well as antibodies formed against various autoantigens, catalytic antibodies against autoantigens, and some viral proteins. We consider various promising targets for developing a vaccine that will not produce unwanted antibodies in vaccinated patients. In addition, we review common problems in the development of a vaccine against HIV-1.

Low hemoglobin levels are associated with direct antiglobulin test positivity in patients with acute-on-chronic liver failure

BACKGROUND

Multiple factors contribute to anemia in patients with Hepatitis B virus (HBV)related acute-on-chronic liver failure (ACLF); however, the mechanism is unclear. The purpose of this study was to evaluate the clinical significance of the direct antiglobulin test (DAT) in patients with HBV related ACLF.

METHODS

DAT was used to detect immunoglobulins and/or complement proteins on the surface of erythrocytes.

RESULTS

We recruited 78 HBV-associated ACLF patients, 30 chronic hepatitis B(CHB)patients and 40 healthy people between October 2015 and May 2016. In HBV related ACLF patients, the hemoglobin concentration, number of erythrocytes, and hematocrit value were significantly lower, while the erythrocyte distribution width was significantly higher, compared to patients with CHB and healthy controls (HCs) (P < 0.001). The rates of DAT positivity in HBV related ACLF patients, CHB patients, and HCs were 62.8 %, 13.3 %, and 0%, respectively. DAT-positive ACLF patients exhibited lower Hb levels, older average age, as well as higher total bilirubin, alanine aminotransferase, and complement component 3 levels compared to DAT-negative patients.

CONCLUSIONS

HBV related ACLF patients showed significant alterations in erythrocyte parameters, possibly reflecting disease development and severity. The high presence of erythrocyte autoantibodies suggested that immunologic clearance of erythrocytes contributed to multifactorial anemia in HBV related ACLF patients.

Autoantibody-Mediated Erythrophagocytosis Increases Tuberculosis Susceptibility in HIV Patients

Macrophage dysfunction is associated with increased tuberculosis (TB) susceptibility in patients with human immunodeficiency virus (HIV) infection. However, the mechanisms underlying how HIV infection impairs macrophage function are unclear. Here, we found that levels of autoantibodies against red blood cells (RBCs) were significantly elevated in patients with HIV as determined by direct antiglobulin test (DAT). DAT positivity was significantly associated with TB incidence in both univariate and multivariate analyses (odds ratio [OR] = 11.96 [confidence interval {CI}, 4.68 to 30.93] and 12.65 [3.33 to 52.75], respectively). Ex vivo analysis showed that autoantibodies against RBCs enhanced erythrophagocytosis and thus significantly impaired macrophage bactericidal function against intracellular Mycobacterium tuberculosis Mechanistically, autoantibody-mediated erythrophagocytosis increased heme oxygenase-1 (HO-1) expression, which inhibited M. tuberculosis-induced autophagy in macrophages. Silencing ATG5, a key component for autophagy, completely abrogated the effect of erythrophagocytosis on macrophage bactericidal activity against M. tuberculosis In conclusion, we have demonstrated that HIV infection increases autoantibody-mediated erythrophagocytosis. This process impairs macrophage bactericidal activity against M. tuberculosis by inhibiting HO-1-associated autophagy. These findings reveal a novel mechanism as to how HIV infection increases TB susceptibility.IMPORTANCE HIV infection significantly increases TB susceptibility due to CD4 T-cell loss and macrophage dysfunction. Although it is relatively clear that CD4 T-cell loss represents a direct effect of HIV infection, the mechanism underlying how HIV infection dampens macrophage function is unknown. Here, we show that HIV infection enhances autoantibody-mediated erythrophagocytosis, which dampens macrophage bactericidal activity against TB by inhibiting HO-1-associated autophagy. Our findings reveal a novel mechanism explaining how HIV infection increases susceptibility to TB. We propose that DAT could be a potential measure to identify HIV patients who are at high TB risk and who would be suitable for anti-TB chemotherapy preventive treatment.

Autoimmune Hemolytic Anemia

Autoimmune hemolytic anemia is an acquired autoimmune disorder resulting in the production of antibodies directed against red blood cell antigens causing shortened erythrocyte survival. The disorders can present as a primary disorder (idiopathic) or secondary to other autoimmune disorders, malignancies, or infections. Treatment involves immune modulation with corticosteroids and other agents.

Autoimmune diseases and HIV infection: A cross-sectional study

To describe the clinical manifestations, treatments, prognosis, and prevalence of autoimmune diseases (ADs) in human immunodeficiency virus (HIV)-infected patients.All HIV-infected patients managed in the Infectious Diseases Department of the Lyon University Hospitals, France, between January 2003 and December 2013 and presenting an AD were retrospectively included.Thirty-six ADs were found among 5186 HIV-infected patients which represents a prevalence of 0.69% including immune thrombocytopenic purpura (n = 15), inflammatory myositis (IM) (n = 4), sarcoidosis (n = 4), Guillain-Barré syndrome (GBS) (n = 4), myasthenia gravis (n = 2), Graves' disease (n = 2), and 1 case of each following conditions: systemic lupus erythematosus, rheumatoid arthritis, autoimmune hepatitis, Hashimoto thyroiditis and autoimmune hemolytic anemia. One patient presented 2 ADs. Thirty patients were known to be HIV-infected when they developed an AD. The AD preceded HIV infection in 2 patients. GBS and HIV infection were diagnosed simultaneously in 3 cases. At AD diagnosis, CD4 T lymphocytes count were higher than 350/mm in 63% of patients, between 200 and 350/mm in 19% and less than 200/mm in 19%. Twenty patients benefited from immunosuppressant treatments, with a good tolerance.ADs during HIV infection are uncommon in this large French cohort. Immune thrombocytopenic purpura, sarcoidosis, IM, and GBS appear to be more frequent than in the general population. Immunosuppressant treatments seem to be effective and well tolerated.

Haematological manifestations of human immune deficiency virus infection

Early in the human immunodeficiency virus (HIV) epidemic, infected patients presented to medical attention with striking abnormalities in each of the major blood cell lineages. The reasons for these derangements remain complex and multifactorial. HIV infects multipotent haematopoietic progenitor cells and establish latent cellular reservoirs, disturbs the bone marrow microenvironment and also causes immune dysregulation. These events lead to cytokine imbalances and disruption of other factors required for normal haematopoiesis. Activation of the reticulo-endothelial system can also result in increased blood cell destruction. The deleterious effects of medications, including first and second generation anti-retroviral agents, on haematopoiesis were well documented in the early years of HIV care; in the current era of HIV-care, the advent of newer and less toxic anti-retroviral drugs have had a more beneficial impact on haematopoiesis. Due to impaired regulation of the immune system and potential side effects of one or more anti-retroviral agents, there is also an increase in coagulation abnormalities such as thromboembolism, and less frequently, acquired disorders of coagulation including thrombotic thrombocytopenic purpura, immune thrombocytopenic purpura and acquired inhibitors of coagulation. In this article we review the epidemiology and aetiology of select non-oncological haematological disorders commonly seen in people living with HIV-acquired immune deficiency syndrome.

Prevalence of HIV-related autoimmune haemolytic anaemia in Lagos, Nigeria

BACKGROUND

Despite a high frequency of anaemia, a positive direct antiglobulin test (DAT) and bone marrow hyperplasia HIV-infected patients, lack of reticulocytosis may cause underdiagnosis autoimmune haemolytic anaemia (AIHA) in them. This study was carried out to determine the prevalence of autoimmune haemolytic anaemia in HIV-infected patients and to compare the haematological/immunological characteristics of subjects with anaemia and those without.

MATERIALS AND METHODS

A total of 350 HIV-infected subjects attending the Lagos University Teaching Hospital who consented were recruited for the study. This included 250 subjects with anaemia (haemoglobin concentration <10 g/dl) as cases and 100 subjects without anaemia as controls. Five milliliters of venous blood drawn from each subject was used for the full blood count, reticulocyte count and DAT.

RESULTS

Subjects with anaemia had lower mean CD4 cell count (284.3 cells/μl) and higher mean reticulocyte per cent (1.5%) than the non-anaemic subjects. The frequency of reticulocytosis was higher in female subjects than in males. Only 0.8% (2 of 250) of the study group screened positive to DAT, p = 0.0339. None of the subjects in control group screened positive to DAT.

CONCLUSION

Autoimmune haemolytic anaemia is a rare complication of HIV infection in our geographical location.

Autoimmune diseases in HIV-infected patients: 52 cases and literature review

OBJECTIVES

1) To describe autoimmune diseases (AD) in HIV-infected people; and 2) to perform a literature review concerning this issue.

DESIGN

52 HIV-infected patients that presented an AD in 14 medical departments in Paris and Ile-de-France area were retrospectively included in this study.

RESULTS

The ADs were vasculitis (11), immune cytopenias (8), rheumatic diseases (8), lupus (7), sarcoidosis (7), thyroid diseases (6), hepatic diseases (5), and antiphospholipid syndrome (4). Four patients presented 2 ADs. In 5 patients the AD preceded HIV infection, in 14 HIV infection was diagnosed at the same time as the AD and 34 were HIV-infected when they developed an AD. 40 ADs (80%) occurred in patients with a CD4 T lymphocyte count of more than 200/mm(3). Cases of autoimmune hemolytic anemia occurred only in patients severely immunodepressed. In five patients (a vasculitis case, a sarcoidosis case, three thyroid disease cases) the AD presented as a form of immune restoration inflammatory syndrome (IRIS). Some ADs allowed HIV-infection diagnosis at a stage of moderate immune deficiency (vasculitis, antiphospholipid syndrome, immune thrombocytopenia). 37 patients received immunosuppressant treatments with good tolerance. These results confirm in a large series of patients previous data concerning autoimmune diseases occurrence in HIV-infected people.

CONCLUSION

In the HAART era, when HIV-infected people are treated more and more early, autoimmune diseases can occur, mainly at the phase of immunological recovery. HIV infection should not limit immunosuppressant treatment use.