# GENETICALLY DETERMINED DEFICIENCY OF C3

> **NIH NIH R01** · JOHNS HOPKINS UNIVERSITY · 1991 · $11,892

## Abstract

The third component of complement (C3) plays a central role in generating
the biologically significant effects of the complement system.  Not only
does activation of C3 create cleavage products (e.g. C3a and C3b) which
directly mediate defensive and inflammatory activities, but the larger
cleavage prouct, C3b, forms part of the enzymes which activate C5-C9.
Thus, C3 is also important in the generation of activities mediated by
C5-C9.

The identification of animals and humans with genetically determined
deficiencies of individual components of complement has been valuable in
generating knowledge about the genetics, biochemistry and biological
significance of the complement system.  Although a few humans with
genetically determined C3 deficiency have been described, until recently no
experimental animals with C3 deficiency had been identified.  In 1981 we
described a colony of dogs with a genetically determined total deficiency
of C3.  the following specific aims are uniquely suited to study in the
C3-deficient dog and should provide important insight into selected aspects
of the role of C3 in immunobiology:

1) We will characterize the renal disease in C3-deficient dogs in order to
gain insight into the etiology and pathogenesis of the renal disease found
in human patients with both inherited and acquired abnormalities in the
complement system.

2) We will study the clearance of soluble immune complexes in C3 deficient
dogs in order to gain insight into the role of C3 in the processing of
immune complexes in vivo.

3) We will determine if C3-deficient dogs have normal antibody formation in
order to clarify the role of C3 in antibody formation in vivo.

4) We will investigate the molecular basis for the C3 deficiency in
C3-deficient dogs in order to gain insight into one possible molecular
mechanisms for genetically determined C3 deficiency.

## Key facts

- **NIH application ID:** 3128641
- **Project number:** 3R01AI019278-08S1
- **Recipient organization:** JOHNS HOPKINS UNIVERSITY
- **SAM.gov UEI:** FTMTDMBR29C7
- **Principal Investigator:** Jerry A Winkelstein
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1991
- **Award amount:** $11,892
- **Award type:** 3
- **Project period:** 1983-07-01 → 1992-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3128641

## Citation

> US National Institutes of Health, RePORTER application 3128641, GENETICALLY DETERMINED DEFICIENCY OF C3 (3R01AI019278-08S1). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/3128641. Licensed CC0.

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