Cleavage of chimpanzee secretory immunoglobulin A by Haemophilus influenzae IgA1 protease

1991 ◽  
Vol 11 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Michael F. Cole ◽  
Cynthia A. Hale
Keyword(s):  
Haemophilus Influenzae ◽  
Immunoglobulin A ◽  
Secretory Immunoglobulin A ◽  
Iga1 Protease ◽  
Secretory Immunoglobulin

scholarly journals Cleavage of the Human Immunoglobulin A1 (IgA1) Hinge Region by IgA1 Proteases Requires Structures in the Fc region of IgA

2003 ◽  
Vol 71 (5) ◽  
pp. 2563-2570 ◽  
Author(s):  
Koteswara R. Chintalacharuvu ◽  
Philip D. Chuang ◽  
Ashley Dragoman ◽  
Christine Z. Fernandez ◽  
Jiazhou Qiu ◽  
...  
Keyword(s):  
Haemophilus Influenzae ◽  
Pathogenic Bacteria ◽  
Immunoglobulin A ◽  
Secretory Immunoglobulin A ◽  
Constant Region ◽  
Wild Type ◽  
Mucosal Surfaces ◽  
Secretory Immunoglobulin

ABSTRACT Secretory immunoglobulin A (IgA) protects the mucosal surfaces against inhaled and ingested pathogens. Many pathogenic bacteria produce IgA1 proteases that cleave in the hinge of IgA1, thus separating the Fab region from the Fc region and making IgA ineffective. Here, we show that Haemophilus influenzae type 1 and Neisseria gonorrhoeae type 2 IgA1 proteases cleave the IgA1 hinge in the context of the constant region of IgA1 or IgA2m(1) but not in the context of IgG2. Both Cα2 and Cα3 but not Cα1 are required for the cleavage of the IgA1 hinge by H. influenzae and N. gonorrhoeae proteases. While there was no difference in the cleavage kinetics between wild-type IgA1 and IgA1 containing only the first GalNAc residue of the O-linked glycans, the absence of N-linked glycans in the Fc increased the ability of the N. gonorrhoeae protease to cleave the IgA1 hinge. Taken together, these results suggest that, in addition to the IgA1 hinge, structures in the Fc region of IgA are required for the recognition and cleavage of IgA1 by the H. influenzae and N. gonorrhoeae proteases.

scholarly journals The immune landscape of IgA induction in the gut

2021 ◽  
Author(s):  
Claudia Seikrit ◽  
Oliver Pabst
Keyword(s):  
Protective Immunity ◽  
Immunoglobulin A ◽  
Antibody Responses ◽  
Dark Side ◽  
Secretory Immunoglobulin A ◽  
Antibody Isotype ◽  
Mucosal Antibody ◽  
Key Concepts ◽  
Basic Understanding ◽  
Secretory Immunoglobulin

AbstractAntibodies are key elements of protective immunity. In the mucosal immune system in particular, secretory immunoglobulin A (SIgA), the most abundantly produced antibody isotype, protects against infections, shields the mucosal surface from toxins and environmental factors, and regulates immune homeostasis and a peaceful coexistence with our microbiota. However, the dark side of IgA biology promotes the formation of immune complexes and provokes pathologies, e.g., IgA nephropathy (IgAN). The precise mechanisms of how IgA responses become deregulated and pathogenic in IgAN remain unresolved. Yet, as the field of microbiota research moved into the limelight, our basic understanding of IgA biology has been taking a leap forward. Here, we discuss the structure of IgA, the anatomical and cellular foundation of mucosal antibody responses, and current concepts of how we envision the interaction of SIgA and the microbiota. We center on key concepts in the field while taking account of both historic findings and exciting new observations to provide a comprehensive groundwork for the understanding of IgA biology from the perspective of a mucosal immunologist.

scholarly journals Fecal Antibodies to Cryptosporidium parvum in Healthy Volunteers

2000 ◽  
Vol 68 (9) ◽  
pp. 5068-5074 ◽  
Author(s):  
Sara M. Dann ◽  
Pablo C. Okhuysen ◽  
Bassam M. Salameh ◽  
Herbert L. DuPont ◽  
Cynthia L. Chappell
Keyword(s):  
Antibody Response ◽  
Healthy Volunteers ◽  
Cryptosporidium Parvum ◽  
Immunoglobulin A ◽  
Reactivity Index ◽  
Secretory Immunoglobulin A ◽  
Low Doses ◽  
Previous Exposure ◽  
Oocyst Excretion ◽  
Secretory Immunoglobulin

ABSTRACT This study examined the intestinal antibody response in 26 healthy volunteers challenged with Cryptosporidium parvum oocysts. Fecal extracts were assayed for total secretory immunoglobulin A (IgA) and C. parvum-specific IgA reactivity. Specific IgA reactivity was standardized to IgA concentration and expressed as a reactivity index (RI). Anti-C. parvum fecal IgA (fIgA) increased significantly in 17 of 26 (65.4%) following oocyst ingestion. Of those with detectable responses, 59, 76.5, and 94.1% were positive by days 7, 14, and 30, respectively. Volunteers receiving high challenge doses (>1,000 and 300 to 500 oocysts) had higher RIs (RI = 5.57 [P = 0.027] and RI = 1.68 [P = 0.039], respectively) than those ingesting low doses (30 to 100 oocysts; RI = 0.146). Subjects shedding oocysts and experiencing a diarrheal illness had the highest fIgA reactivity. When evaluated separately, oocyst excretion was associated with an increased fIgA response compared to nonshedders (RI = 1.679 versus 0.024, respectively; P = 0.003). However, in subjects experiencing diarrhea with or without oocyst shedding, a trend toward a higher RI (P = 0.065) was seen. Extracts positive for fecal IgA were further examined for IgA subclass. The majority of stools contained both IgA1 and IgA2, and the relative proportions did not change following challenge. Also, no C. parvum-specific IgM or IgG was detected in fecal extracts. Thus, fecal IgA to C. parvum antigens was highly associated with infection in subjects who had no evidence of previous exposure and may provide a useful tool in detecting recent infections.

Sign in / Sign up

Export Citation Format

Share Document