Anti‑Human glycoprotein hormone α‑subunit (pan‑hCG/FSH/LH) (Clone 176) — Purified

Purified Recombinant Human FSH (>98%)

This purified antibody is supplied in 0.05 M phosphate buffered saline (PBS), pH 7.2 - 7.4, containing 0.1% sodium azide. as a preservative.

This Purified Antibody is stable when stored at 2-8°C. Do not freeze.

hCG Test

When paired with Leinco Prod. No. C102 (Clone 151), this antibody detects intact hCG (ihCG) at 100% with cross reactivity of < 4% for LH, < 2% for FSH, and < 1% for TSH.

When paired with Leinco Prod. No. C103 (Clone 152), this antibody detects intact hCG at 100% with cross reactivity of < 1% for βhCG, < 2% for LH, < 1% for FSH, and < 1% for TSH.

When paired with Leinco Prod. No. C104 (Clone 208), this antibody detects intact hCG at 100% with cross reactivity of < 1% for βhCG, LH, FSH, and TSH.

FSH Test

When paired with Leinco Prod. No. F102 (Clone 181), this antibody detects FSH at 100% with cross reactivity of < 1% for βhCG, < 4% for LH, and < 1% for TSH.

NOTE: In this FSH assay format, 3,000 mIU/ml hCG may causes a 4% decrease in observed FSH; at higher hCG concentrations, the observed FSH signal is reduced to zero.

LH Test

When paired with Leinco Prod. No. L100 (Clone 196), this antibody detects LH at 100% with cross reactivity of < 1% for βhCG, < 1% for FSH, 57% for intact hCG, and < 1% for TSH.

When paired with Leinco Prod. No. L101 (Clone 199), this antibody detects LH at 100% with cross reactivity of < 1% for βhCG, < 1% for FSH, 7% for intact hCG, and < 1% for TSH. Note: In this format, 3,000 mIU/ml hCG produces a 6% increase in the observed LH signal.

Next Day 2-8°C

Clone 176 was generated using recombinant human FSH as immunogen and recognizes the glycoprotein hormone α‑subunit, enabling detection of FSH as well as cross‑reactive binding to LH and hCG in immunoassay formats, consistent with a pan‑glycoprotein hormone α‑subunit specificity profile.

Follicle‑stimulating hormone (FSH), luteinizing hormone (LH), thyroid‑stimulating hormone (TSH), and human chorionic gonadotropin (hCG) are heterodimeric glycoprotein hormones composed of a common α‑subunit paired with a hormone‑specific β‑subunit. The shared α‑subunit carries conserved epitopes that allow pan‑reactive monoclonal antibodies to recognize multiple members of this hormone family, while the unique β‑subunits confer biological and receptor specificity to each hormone. Clone 176 was generated using recombinant human FSH as immunogen and recognizes the glycoprotein hormone α‑subunit, enabling detection of FSH as well as cross‑reactive binding to LH and hCG in immunoassay formats, consistent with a pan‑glycoprotein hormone α‑subunit specificity profile defined in in‑house testing.
The Strategic Advantage of α‑subunit Targeting: The suitability of Clone 176 as a capture reagent stems from the structural biology of the glycoprotein hormone family. Because Follicle-stimulating hormone (FSH), Luteinizing hormone (LH), Thyroid-stimulating hormone (TSH), and human chorionic gonadotropin (hCG) share an identical alpha-subunit, targeting this region offers unique benefits in immunoassay architecture.

Here is a detailed breakdown of why this profile is highly advantageous for diagnostics:

1. The "Universal Capture" Strategy
In a typical "sandwich" immunoassay (such as ELISA or Lateral Flow), two antibodies are required: a capture antibody (immobilized) and a detection antibody (labeled).
- Simplified Manufacturing: By using Clone 176 as a pan-reactive capture antibody, a diagnostic manufacturer can use the exact same solid-phase coating (plate, bead, or membrane) for four distinct assays (FSH, LH, TSH, and hCG).
- Specificity via Detection: The specificity of the assay is then determined by the detection antibody, which would target the unique beta-subunit of the specific hormone being measured.
-Benefit: This reduces manufacturing complexity, lowers inventory costs for raw materials, and creates a standardized coating protocol across multiple product lines.

2. Optimal Epitope Accessibility (Steric Orientation):
When designing a sandwich assay, the capture and detection antibodies must bind to the antigen simultaneously without interfering with one another.

- Spatial Separation: Because Clone 176 targets the common alpha-subunit, it effectively anchors the hormone by its "shared" side. This structurally leaves the hormone-specific beta-subunit fully exposed and solvent-accessible.
- High Sensitivity: This orientation minimizes steric hindrance, allowing the beta-specific detection antibody to bind with high affinity. This is critical for high-sensitivity assays where the goal is to capture the analyte without blocking the unique identification site.

- 3. High Affinity and Stability:
Conserved structural regions, such as the glycoprotein alpha-subunit, are often structurally rigid to maintain compatibility with multiple beta-partners.
-Robust Capture: Antibodies targeting these conserved, stable regions often exhibit excellent binding kinetics. A strong capture reagent is essential for retaining the analyte during wash steps in an ELISA or maximizing capture efficiency in rapid flow-through systems.

4. Versatility in Multiplexing:
For platforms designed to measure multiple hormones simultaneously (multiplexing), Clone 176 is an ideal candidate. Single-Step Capture: In a multiplexed array, Clone 176 can serve as a single capture agent that pulls all glycoprotein hormones out of a serum sample. Differentiated signals can then be generated using distinct detection antibodies labeled with unique fluorophores or reporters for FSH, LH, and hCG respectively.

Conclusion:Clone 176 is not just an antibody for FSH; it is a platform-enabling reagent. Its ability to recognize the conserved alpha-subunit allows it to function as the foundational anchor in a matched pair, relying on a secondary reagent to provide the necessary biological specificity. This makes it a cost-effective, versatile, and structurally favorable choice for developing a suite of reproductive and metabolic hormone assays.

1.) Ramabhadran TV, Reitz BA, Tiemeier DC. Synthesis and glycosylation of the common alpha subunit of human glycoprotein hormones in mouse cells. Proc Natl Acad Sci U S A. 1984 Nov;81(21):6701-5. doi: 10.1073/pnas.81.21.6701. PMID: 6208554; PMCID: PMC391998.