Related Experiment Video

Updated: Jul 20, 2026

Antigen-Capture Enzyme-Linked Immunosorbent Assay for Specific Detection of Mycoplasma pneumoniae
06:04

Antigen-Capture Enzyme-Linked Immunosorbent Assay for Specific Detection of Mycoplasma pneumoniae

Published on: February 24, 2023

Antibody response to Pneumocystis jirovecii major surface glycoprotein

Kieran R Daly1, Laurence Huang, Alison Morris

  • 1Research Service 151, Veterans Affairs Medical Center, 3200 Vine Street, Cincinnati, OH 45220, USA.

Emerging Infectious Diseases
|September 13, 2006
PubMed

Insights

Antibody levels to Pneumocystis jirovecii major surface glycoprotein (Msg) fragments were similar in HIV patients. However, MsgC antibodies rose significantly after Pneumocystis pneumonia recovery, indicating its potential as a diagnostic marker.

Area of Science:

  • Immunology
  • Infectious Diseases
  • Microbiology

Background:

  • Pneumocystis jirovecii pneumonia (PCP) is a significant opportunistic infection in HIV-infected individuals.
  • Diagnosis of PCP can be challenging, particularly in resource-limited settings.
  • The major surface glycoprotein (Msg) of P. jirovecii is a key target for immune responses.

Purpose of the Study:

  • To investigate the serologic responses to recombinant fragments of P. jirovecii Msg in HIV-infected patients.
  • To identify potential serologic markers for PCP diagnosis and monitoring.

Main Methods:

  • Prospective pilot study design.
  • Enzyme-linked immunosorbent assay (ELISA) to measure antibody levels against overlapping Msg fragments.
  • Comparison of antibody levels between HIV patients with PCP and those with other pneumonias.

Main Results:

  • Similar baseline antibody levels to Msg fragments were observed in both patient groups.
  • A significant rise in serum antibodies to the MsgC fragment was detected 3-4 weeks post-recovery in PCP patients (p<0.001).
  • Higher baseline CD4+ counts (> or =50 cells/microL) and a first episode of PCP were associated with this antibody rise (p<0.001).

Conclusions:

  • The MsgC fragment shows promise as a serologic reagent for P. jirovecii infection.
  • Further clinical and epidemiologic studies are warranted to validate MsgC's utility.
  • Serologic responses to MsgC may aid in diagnosing and monitoring PCP in HIV-infected populations.

More Related Videos

Opsonophagocytic Killing Assay to Assess Immunological Responses Against Bacterial Pathogens08:47

Opsonophagocytic Killing Assay to Assess Immunological Responses Against Bacterial Pathogens

Published on: April 5, 2019

Capsular Serotyping of Streptococcus pneumoniae by Latex Agglutination09:11

Capsular Serotyping of Streptococcus pneumoniae by Latex Agglutination

Published on: September 25, 2014

Related Concept Videos

Humoral Immune Responses01:36

Humoral Immune Responses

Overview
Immune Response Against Viral Pathogens01:29

Immune Response Against Viral Pathogens

The immune system's response to viral infections is a complex and coordinated process involving natural killer (NK) cells, T cell-mediated responses, and antibody-mediated responses.
NK Cells
NK cells are a crucial part of our innate immune system, acting as the first line of defense against viral infections. These cells can recognize and kill infected cells without prior exposure to the virus, effectively slowing down the spread of infection. Additionally, NK cells produce proinflammatory...
Atypical Pneumonia01:14

Atypical Pneumonia

Atypical pneumonia, often caused by Mycoplasma pneumoniae, is a form of pulmonary infection that differs from the classical presentation of bacterial pneumonia in both its cause and clinical symptoms. Mycoplasma pneumoniae is a pleomorphic bacterium notable for its lack of a rigid cell wall. This structural characteristic imparts resistance to beta-lactam antibiotics and significantly influences the bacterium’s behavior within the human host.Other pathogens responsible for the disease include...
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.
Respiratory Syncytial Virus Disease01:29

Respiratory Syncytial Virus Disease

Human respiratory syncytial virus (RSV) is a widespread pathogen that primarily targets infants and young children but also poses a serious health risk to elderly and immunocompromised individuals. Belonging to the Pneumoviridae family, RSV is a negative-sense, single-stranded RNA virus within the Pneumovirus genus. Its global health burden is significant, with millions of cases annually resulting in hospitalizations and mortality, particularly in resource-limited settings. Although most...
Cross-reactivity00:42

Cross-reactivity

Overview