United States Patent 5,460,977: Claim Scope, Strength, and US Landscape

US Patent 5,460,977 claims defined peptides derived from the Der f II allergen of Dermatophagoides farinae, and uses them in lymphocyte blastogenesis assays for mite allergy diagnosis (claims 1-6 and 7-8). The core patentable subject matter sits in (i) peptide sequence selection and (ii) mapping those sequences to a specific immunological readout (thymidine incorporation) in a defined lymphocyte exposure protocol.

What does US 5,460,977 actually claim?

Claim set overview

The independent claim is claim 1, which is peptide-centric and limited by two tethering constraints:
1) the peptide causes lymphocyte blast formation after sensitization by mites, and
2) the peptide is part of the Der f II allergen.

Dependent claims 2-6 narrow to specific lengths and explicit residue compositions for five peptide formulas (I)-(V), with SEQ ID NO:1 for formula (I) and SEQ ID NO:2 for formula (III). Claim 7 is a formulation claim for a diagnostic agent. Claim 8 recites a diagnostic method using separate exposure to each peptide formula, plus radioactive thymidine and measurement of incorporation.

Scope by claim

Claim	Scope type	Limiting elements	Practical meaning
1	Composition (peptide)	Peptide causes blast formation of mite-sensitized lymphocytes; peptide selected from peptides of formulas (I)-(V); peptide is part of Der f II (D. farinae)	Broadest claim; still constrained to Der f II-derived fragments with an immunological function
2	Composition (specific member)	Pentadecapeptide; formula (I); specific residues listed for Asp, Gln, Val, Lys, Cys, Ala, Asn, Glu, Ile	Narrows to one length and one defined sequence form
3	Composition (specific member)	Triacontapeptide; formula (II); residues include Lys, (Cys)2 treated as a cystine motif	Narrows to another defined fragment length and composition
4	Composition (specific member)	Pentadecapeptide; formula (III); residues list includes Gly, Asp, Val, Lys, Cys, Ala, Ile, Leu, Thr, His, Arg	Narrows to a third specific fragment
5	Composition (specific member)	Triacontapeptide; formula (IV)	Narrows to the fourth fragment
6	Composition (specific member)	Triacontapeptide; formula (V)	Narrows to the fifth fragment
7	Diagnostic agent	Contains peptide of claim 1	Downstream product claim linked directly to claim 1 peptides
8	Method	Separate exposure of patient lymphocytes to peptides of (I)-(V); add radioactive labeled thymidine; measure incorporated label	Procedure claim tied to the five specific peptides and a particular assay readout

How strong are the claim anchors and where are the pressure points?

1) Functional limitation: “causes blast formation of lymphocytes sensitized by mites” (claim 1, claim set)

This language imports a biological activity requirement into the composition claim. For enforcement, that can help establish that the claimed peptides are not merely arbitrary Der f II fragments but are immunologically active fragments in the specific blastogenesis context.

Pressure point: functional statements are often litigated around whether the accused product has the claimed function under the claimed conditions. The method claim 8 bakes in those conditions (separately exposing lymphocytes to each peptide and using thymidine incorporation), which can make the function limitation easier to test in an infringement dispute.

2) Origin limitation: “part of the Der f II allergen of Dermatophagoides farinae” (claim 1)

This is an important structural anchor. It reduces the universe from all possible mite-related peptides to peptides derived from a specific allergen.

Pressure point: “part of” is not a tight sequence identity definition by itself. In practice, it maps to sequence-derived fragments within Der f II. The dependent claims then reduce ambiguity by pinning five formulae (I)-(V).

3) Specificity: formulas (I)-(V) with pentadecapeptide/triacontapeptide lengths (claims 2-6)

The patent’s practical enforceability rises with the clarity of what peptide sequences are claimed. Claims 2-6 provide explicit residue-position definitions in formula form, and claim 1 points to those formulas.

Pressure point: the claim text you provided shows formulas as images/structures. The exact amino-acid ordering must be interpreted from the formula drawings, and any ambiguous translation can create claim construction risk. For a litigation posture, the written description and sequence identifiers (SEQ ID NO:1 and SEQ ID NO:2) matter, but they are not fully visible in the provided claim excerpt.

4) Assay constraint in claim 8: thymidine incorporation after separate exposure

Claim 8 is procedurally narrow in two ways:

the lymphocytes are separately exposed to each of the peptides of formulas (I)-(V), and
the readout uses radioactive labeled thymidine and measures incorporation.

Pressure point: if a competitor uses an immunological readout that correlates with blast formation but not thymidine incorporation, claim 8 may not read on it. Claim 7 could still be relevant if the peptide content is identical.

What is the likely prior-art posture and where could validity be attacked?

The patent is about:

peptides derived from an allergen (Der f II) and
their ability to induce T-cell proliferation / lymphocyte blastogenesis in mite-allergic context,
plus diagnostic use via radioactive thymidine incorporation.

Common validity attack routes for this fact pattern are:

1) Anticipation of the peptide sequences
If earlier publications or patents disclosed the same Der f II fragments (or essentially identical sequences) with similar immunological behavior, claim 1’s novelty collapses.

2) Anticipation of the diagnostic method
If earlier art taught that lymphocytes from mite-allergic patients respond to Der f II (or fragments) with thymidine incorporation readouts, claim 8 may be vulnerable, especially if the peptide panel was already proposed.

3) Obviousness (combination of known elements)
Even if the precise five peptides were not explicitly disclosed, an examiner could treat peptide fragmentation from a known allergen and standard proliferation assays as an obvious combination.

4) Written description / enablement with functional limitation
Where claim 1 contains a functional activity limitation, examiners often scrutinize whether the application supports that all encompassed peptides cause blast formation across relevant patient variability and assay conditions.

The claim set’s structure mitigates some of these risks by tying to five specific formula-defined peptides, but the “functional blast formation” limitation can still lead to scrutiny if the specification does not provide robust, reproducible evidence for each peptide and each condition.

How does the claim strategy interact with enforceability?

Composition vs method decoupling

Claim 7 is a product formulation claim for a diagnostic agent containing the claim 1 peptide(s).
Claim 8 is a method of diagnosing that ties to a specific assay protocol.

This creates a bifurcated enforcement pathway:

If an accused diagnostic uses the claimed peptide sequences but changes the assay readout, claim 7 can still bite.
If an accused diagnostic uses the same assay but uses different peptides, claim 8 may fail while claim 7 also fails because it depends on claim 1 peptides.

Panel approach in claim 8

Claim 8’s “separately exposing lymphocytes … to each of the peptides … (I) to (V)” is a meaningful limitation. Competitors using pooled peptides or using only a subset of those peptides can avoid literal infringement, depending on how courts construe “each” and whether partial performance can still practice the claim.

Where is the landscape likely crowded?

The patent’s subject is an allergen-derived T-cell epitope approach and a classical proliferation diagnostic readout. Historically, this area tends to be populated by:

allergen cloning and mapping papers,
T-cell epitope identification patents and publications,
and assay methodology patents for lymphocyte proliferation diagnostics using thymidine incorporation.

Without the full prosecution history and without the full specification text, the best business-grade inference is structural: the claim set focuses narrowly on Der f II fragment panels and ties them to thymidine incorporation. That often means:

the patent’s differentiation is in the specific five peptides and their exact sequences, not in the general concept of measuring lymphocyte proliferation to mite allergens.

Accordingly, the most decisive differentiator in the landscape is whether competitors and earlier filings disclosed these same five Der f II fragments as candidate T-cell epitopes.

Claim-by-claim critical assessment

Claim 1 (broadest): functional + origin + membership

Strengths
- “part of Der f II (D. farinae)” is a firm biological source limitation.
- membership restriction to (I)-(V) constrains the peptide space.
Vulnerabilities
- “selected from the group consisting of peptides of formula (I)-(V)” makes this a closed set, which is good for novelty but increases dependence on correct sequence interpretation of those formulas.
- functional language can be used in validity arguments if the specification does not support activity for all encompassed peptides, or if prior art shows the same fragments with similar activity.

Claims 2 and 4 (pentadecapeptides)

Strengths
- length and explicit residue list are narrowing.
Vulnerabilities
- if prior art disclosed Der f II fragments with same length and residue composition, claim construction becomes critical on sequence identity.

Claims 3, 5, 6 (triacontapeptides)

Strengths
- explicit cystine handling in formulas with (Cys)2 suggests defined disulfide-linked or cystine-containing motif.
Vulnerabilities
- triacontapeptides are long enough that many peptide-mapping schemes could yield overlapping fragments. Prior art that discloses a larger Der f II fragment pool can create overlap arguments in obviousness even if exact matches are not present.

Claim 7 (diagnostic agent)

Strengths
- product claim aligned with a closed peptide set.
Vulnerabilities
- if competitor sells an assay kit that does not contain exactly claim 1 peptides, or uses recombinant allergens/other fragments, claim 7 may not read.

Claim 8 (diagnostic method)

Strengths
- procedural specificity: separate exposure to each peptide in (I)-(V) and radioactive thymidine incorporation.
Vulnerabilities
- many modern diagnostics replace radioactive readouts (or pool stimuli). If the market has moved to non-radioactive proliferation markers, claim 8 can be easy to design around.
- claim 8 requires the specific panel (I)-(V). Use of a different epitope set likely avoids literal infringement.

Business implications for R&D and licensing

Design-around analysis

Changing assay readout away from radioactive thymidine incorporation can avoid claim 8.
Using pooled peptides rather than “separately exposing” to each of (I)-(V) can reduce literal coverage, depending on claim construction.
Using a different Der f II-derived epitope panel not matching formulas (I)-(V) can avoid both claim 1 and claim 7.

Where licensing leverage likely sits

The most commercially relevant hook is that claim 8 and claim 7 tie directly to a fixed peptide panel from a specific allergen. If competitors or partners already use those specific fragments, licensing leverage is strong because:

it is not a broad platform claim,
it is a constrained, testable panel claim.

Key Takeaways

US 5,460,977 is a Der f II epitope peptide panel patent paired to a T-cell proliferation diagnostic workflow (thymidine incorporation).
Claim 1 is constrained to a closed list of five formula-defined peptides and requires that each peptide is a Der f II fragment that drives mite-sensitized lymphocyte blast formation.
Claims 2-6 lock down peptide members by sequence/length formulas, while claim 8 narrows the diagnostic method to separate peptide exposure plus radioactive thymidine incorporation.
For validity and infringement, the decisive issue is whether earlier art disclosed the same Der f II fragments (or clear equivalents) and whether the diagnostic method elements were already known for that panel.

FAQs

1) What is the diagnostic principle in US 5,460,977?

It measures lymphocyte proliferation/blast formation using radioactive labeled thymidine incorporation after separate exposure to the claimed Der f II peptide panel.

2) Are the peptides in claim 1 open-ended?

No. Claim 1 is limited to a closed group of peptides defined by formulas (I) to (V) that are part of Der f II from Dermatophagoides farinae.

3) Can a competitor avoid the method claim by changing the readout?

Yes. Claim 8 explicitly requires radioactive labeled thymidine and measuring its incorporation, so alternative readouts can avoid literal claim coverage.

4) Does the product claim (claim 7) depend on the method?

Claim 7 depends on peptide identity: it covers a diagnostic agent comprising the claim 1 peptide. It does not require practicing claim 8.

5) What is the highest-value infringement test?

Whether an accused product or assay uses peptide sequences that match formulas (I)-(V) (Der f II fragments) and, for method practice, whether it performs the separate exposure and radioactive thymidine incorporation workflow.

References

[1] US Patent 5,460,977. “Peptides from the Der f II allergen of Dermatophagoides farinae and diagnostic uses thereof.” (claims 1-8 as provided in the user prompt).

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Greer Laboratories, Inc.	N/A	insects (whole body), mite dermatophagoides farinae	Injection	101834	September 15, 1958	5,460,977	2014-03-30
>Applicant	>Tradename	>Biologic Ingredient	>Dosage Form	>BLA	>Approval Date	>Patent No.	>Expiredate

Patent: 5,460,977

Summary for Patent: 5,460,977