SYNTHETIC PEPTIDES WHICH INHIBIT THE INTERACTION BETWEEN C1q AND IMMUNOGLOBULIN AND PROLONG XENOGRAFT SURVIVAL1

Fryer, Jonathan P.; Leventhal, Joseph R.; Pao, Winnie; Stadler, Cristina; Jones, Marcia Thornton; Walsh, Thomas E.; Zhong, Robert; Zheng, Zhaohui; Wang, Hao; Goodman, D.J.; Kurek, Margarita; d’Apice, Anthony J.F.; Blondin, B; Ivancic, David; Buckingham, F; Kaufman, Dixon B.; Abecassis, Michael; Stuart, Frank P.; Anderson, Byron

doi:10.1097/00007890-200009150-00021

Cited by 24 publications

(7 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While this is not always practical, it can be achieved for the majority of reagents with careful thought. Finally, the addition prior to sample preparation of a high affinity C1q inhibitor offers the potential for the complete inhibition of this artifact (5,16), but requires further development.…”

Section: Discussionmentioning

confidence: 99%

“…WY-BSA consists of the dipeptide tryptophan-tyrosine multiply conjugated to bovine serum albumin (BSA), and has been shown to be an inhibitor of complement C1q (5). When used, the synthetic inhibitor was added to 5 ml of whole blood to a final concentration of 10 mM/l and incubated for 15 min at room temperature prior to the processing by the standard whole blood lysis assay.…”

Section: Wy-bsamentioning

confidence: 99%

See 1 more Smart Citation

Interactions between mouse IgG2 antibodies are common and mediated by plasma C1q

Wood¹,

Levin²

2006

Cytometry Part B Clinical

View full text Add to dashboard Cite

Background: The simultaneous use of multiple antibodies for multicolor flow cytometry is increasingly common and presents the opportunity for antibody interactions.Methods: Antibodies of differing isotypes were evaluated in pair-wise combinations for the presence of antibody interactions, using a standard whole blood lysing method or variations thereof.Results: Artifactual interactions were identified and preferentially involved IgG2a (58%) or IgG2b (33%) antibodies and a single IgG1 antibody (3%). The interactions were present in all 10 random peripheral blood samples evaluated and required only whole blood and the two antibodies. Plasma removal prior to antibody incubation eliminated the interaction, as did switching any single IgG2 antibody to an IgG1 clone. Heat-inactivated plasma eliminated the interactions, and the addition of purified C1q to washed cells was capable of recreating the interaction in its entirety, confirming the mediation by complement C1q.Conclusions: Complement C1q mediates significant interactions between mouse IgG2 class antibodies; these interactions are very common and may be prevented by either complete serum removal or use of alternate IgG1 clones. Such interactions represent a significant potential source of artifact in the use of whole blood lysis methods for specimen preparation for multicolor flow cytometry.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Wy-bsamentioning

confidence: 99%

Interactions between mouse IgG2 antibodies are common and mediated by plasma C1q

Wood¹,

Levin²

2006

Cytometry Part B Clinical

View full text Add to dashboard Cite

show abstract

“…An 11-meric peptide derived from the constant region of IgG1 inhibits the lysis of pig erythrocytes by human serum in the millimolar range (21). Furthermore, a dimeric peptide WY, derived from the C H 2 domain of human IgG, inhibits lysis of EA, also in the millimolar range (22). Multimeric forms of these peptides had a strongly increased potency.…”

Section: Discussionmentioning

confidence: 99%

“…A related strategy for the development of C1q inhibitors is the synthesis of protein parts of the C1q molecule that can act as a competitive inhibitor of ligand binding. For this purpose, a 12-meric peptide was developed from the B chain of the globular head region of C1q (ghB) that inhibits complement-mediated lysis of EA with an IC 50 of 130 M (22). Furthermore, the ghB expressed as a fusion protein with maltose binding protein inhibits the lysis of EA (28,29), and slightly better results were obtained with a trimerized ghB protein (29).…”

Section: Discussionmentioning

confidence: 99%

Specific Inhibition of the Classical Complement Pathway by C1q-Binding Peptides

Roos¹,

Nauta²,

Broers³

et al. 2001

The Journal of Immunology

View full text Add to dashboard Cite

Undesired activation of the complement system is a major pathogenic factor contributing to various immune complex diseases and conditions such as hyperacute xenograft rejection. We aim for prevention of complement-mediated damage by specific inhibition of the classical complement pathway, thus not affecting the antimicrobial functions of the complement system via the alternative pathway and the lectin pathway. Therefore, 42 peptides previously selected from phage-displayed peptide libraries on basis of C1q binding were synthesized and examined for their ability to inhibit the function of C1q. From seven peptides that showed inhibition of C1q hemolytic activity but no inhibition of the alternative complement pathway, one peptide (2J) was selected and further studied. Peptide 2J inhibited the hemolytic activity of C1q from human, chimpanzee, rhesus monkey, rat, and mouse origin, all with a similar dose-response relationship (IC50 2–6 μM). Binding of C1q to peptide 2J involved the globular head domain of C1q. In line with this interaction, peptide 2J dose-dependently inhibited the binding of C1q to IgG and blocked activation of C4 and C3 and formation of C5b-9 induced via classical pathway activation, as assessed by ELISA. Furthermore, the peptide strongly inhibited the deposition of C4 and C3 on pig cells following their exposure to human xenoreactive Abs and complement. We conclude that peptide 2J is a promising reagent for the development of a therapeutic inhibitor of the earliest step of the classical complement pathway, i.e., the binding of C1q to its target.

show abstract

“…A superior approach would be to eliminate the expression of αGal in the pig, as discussed above. Specific peptides inhibitors of C1q, to achieve more complete complement inhibition, may be required as adjunctive therapy, 62 although efficacy in a pig‐to‐primate model is yet to be determined.…”

Section: Xenograft Rejection: the Immunological Responsementioning

confidence: 99%

Xenotransplantation: Past achievements and future promise

Dwyer

Cowan

d’Apice

2002

Heart, Lung and Circulation

View full text Add to dashboard Cite

SYNTHETIC PEPTIDES WHICH INHIBIT THE INTERACTION BETWEEN C1q AND IMMUNOGLOBULIN AND PROLONG XENOGRAFT SURVIVAL1

Abstract: The CBP2 and WY peptides exhibit the functional activity of inhibition of complement activation. These peptides also prolong xenograft survival and thus provide reagents for the study of the importance of C1q and other complement components in transplant rejection mechanisms.

Cited by 24 publications

References 35 publications

Interactions between mouse IgG2 antibodies are common and mediated by plasma C1q

Interactions between mouse IgG2 antibodies are common and mediated by plasma C1q

Specific Inhibition of the Classical Complement Pathway by C1q-Binding Peptides

Xenotransplantation: Past achievements and future promise

Contact Info

Product

Resources

About