# BIOCHEMISTRY OF COMPLEMENT FACTOR B

> **NIH NIH R01** · UNIV OF MASSACHUSETTS MED SCH WORCESTER · 1989 · $143,279

## Abstract

The goal is to identify and define the various regulatory processes which
are involved in the induction, biosynthesis and secretion of factor D as
well as mechanisms for its enzymatic activation and regulation.  Factor D
is a trace serum protease which is absolutely essential for activation of
the alternative pathway of complement and has been hypothesized to exist in
serum only as the active enzyme.  Despite its key role in the formation of
the C3 convertase, very little information is currently available on its
cellular expression and regulation.  Very recent structural analysis of a
cDNA clone for factor D in our laboratory has demonstrated that the protein
must be synthesized as a zymogen.  This project will attempt to extend
these studies and focus attention on elucidation of the key steps which are
important for activation of the zymogen and for control of its activity in
serum.  The specific objectives are:  1) to clone and sequence full-length
cDNA for factor D, 2) to isolate and examine the organization of the factor
D genome and identify potential regulatory sites in the gene structure
which may be important in its expression, 3) to map the chromosomal
location of the factor D gene using human-rodent somatic-cell hybrids, 4)
to search for evidence of restriction fragment length polymorphisms, 5) to
prepare monosppecific, polyclonal antisera using synthetic peptides
corresponding to specific deduced sequences in the zymogen, 6) to
investigate the induction, synthesis, secretion and mechanism of activation
of the zymogen, 7) to examine the possibility that natural inhibitor(s) of
factor D activity are present in serum, 8) to characterize the putative
protease which is hypothesized to convert the proenzyme of factor D to the
active form found in the factor D convertase, 10) to investigate the
potential of using expression-vector systems in order to produce
large-scale amounts of the precursor.  Together such studies will provide
additional insight into the regulation and expression of factor D and
should contribute to a better understanding of how the early events in the
activation of the alternative pathway of complement function in both host
defense reactions and in the pathogenesis of human inflammatory diseases.

## Key facts

- **NIH application ID:** 3128705
- **Project number:** 5R01AI019337-08
- **Recipient organization:** UNIV OF MASSACHUSETTS MED SCH WORCESTER
- **SAM.gov UEI:** MQE2JHHJW9Q8
- **Principal Investigator:** JOHN E MOLE
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1989
- **Award amount:** $143,279
- **Award type:** 5
- **Project period:** 1982-01-01 → 1991-01-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3128705

## Citation

> US National Institutes of Health, RePORTER application 3128705, BIOCHEMISTRY OF COMPLEMENT FACTOR B (5R01AI019337-08). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/3128705. Licensed CC0.

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