Mycobacterium avium complex disease in patients with AIDS: seroreactivity to native and recombinant mycobacterial

S L Morris1, L Bermudez, S D Chaparas

  • 1Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892.

Antibodies to Mycobacterium avium complex (MAC) antigens were measured by enzyme-linked immunosorbent assays and immunoblot analyses in sera from 20 patients with AIDS and disseminated MAC disease, 5 human immunodeficiency virus-seronegative patients with pulmonary MAC infections, and 20 healthy controls. Whereas enzyme-linked immunosorbent assay titers for healthy controls and patients with AIDS and MAC disease were comparable, human immunodeficiency virus-seronegative patients with MAC disease had higher anti-MAC antibody titers (P less than 0.01). Immunoblot analysis with the same sonic extracts indicated that each of the three groups had a limited heterogeneous response to M. avium antigens. No significant differences in immunoblot reactivities were detected. However, immunoblot studies with recombinant nontuberculous mycobacterial antigens revealed that sera from over 90% of the patients with MAC disease and only 25% of controls recognized a recombinant protein derived from a 35-kDa mycobacterial antigen. Although sonic extracts did not permit adequate discrimination of antibody reactivity in patients with MAC disease, recombinant antigens may be useful as indicators of disease.

Related Concept Videos

Antigens Involved in Adaptive Immunity01:26

Antigens Involved in Adaptive Immunity

An antigen is any substance the immune system identifies as foreign and potentially harmful to the body, prompting an immune response. Antigens have two functional properties: immunogenicity and reactivity. Immunogenicity is the ability of an antigen to stimulate a specific immune response. At the same time, reactivity describes the antigen's ability to react with the cells and antibodies produced in response to it.
Complete Antigens
Complete antigens possess both immunogenicity and reactivity.
Immunodeficiency Diseases01:25

Immunodeficiency Diseases

Immunodeficiency disorders are conditions in which the immune system's ability to fight infectious disease and cancer is compromised or entirely absent. The immune system comprises a complex network of cells, tissues, and organs that work together to protect the body from potentially harmful invaders. When this system is deficient or not functioning properly, it leaves the body susceptible to infections, diseases, or other complications.
There are three main causes of immunodeficiency disorders...
Pulmonary Tuberculosis I01:29

Pulmonary Tuberculosis I

Tuberculosis, often called TB, is a contagious illness primarily caused by Mycobacterium tuberculosis. It mainly affects the lung parenchyma but can also impact other body parts.
Causative Organism
The primary infectious agent causing tuberculosis is Mycobacterium tuberculosis, a slow-growing, acid-fast, aerobic rod that exhibits sensitivity to heat and ultraviolet light. Instances of Mycobacterium bovis and Mycobacterium avium contributing to the development of TB infection are rare.
Mode of...
Tuberculosis01:23

Tuberculosis

Tuberculosis (TB) remains a significant global health concern, primarily targeting the lungs and spreading through airborne transmission. Infection begins when aerosolized droplet nuclei, expelled by an individual with active TB, are inhaled by another person. These microscopic particles carry Mycobacterium tuberculosis, the causative agent of TB. Upon reaching the alveoli, the bacilli are engulfed by alveolar macrophages. However, due to their specialized lipid-rich cell wall, these pathogens...
Cytomegalovirus Disease01:27

Cytomegalovirus Disease

Cytomegalovirus (CMV) disease is caused by human cytomegalovirus, a double-stranded DNA virus of the Herpesviridae family. While primary CMV infection is often asymptomatic in immunocompetent individuals, the virus can cause severe disease in neonates and immunocompromised patients. CMV is the most common cause of congenital viral infection in the United States, and a major pathogen in solid organ and hematopoietic stem cell transplant recipients.CMV is transmitted via bodily fluids, sexual...
Cryptococcal Meningitis01:27

Cryptococcal Meningitis

Cryptococcal meningitis is a life-threatening opportunistic infection predominantly associated with HIV/AIDS, accounting for over 100,000 deaths annually worldwide. However, it also affects individuals with other forms of immunosuppression, including those undergoing immunosuppressive therapy, organ transplant recipients, patients with innate immunodeficiencies, and individuals with hematological disorders. The infection is caused mainly by Cryptococcus neoformans and Cryptococcus gattii,...