ANA vs. ANCA

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ANA vs. ANCA

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LilInjnDatCould
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Topics: 2
Posts: 72

08/29/07 - 10:07 AM

Hello budding Pathologists!!

I am going through the "classical findings" section in the back of FirstAid and I am a unclear and wanted to know if some of you would shed some light for me.

So is Antineutrophil antibodies (ANA), which results in Vasculitis, the same as AntiNeutrophilCyoplasmicAntibodies (ANCA)? C-ANCA and P-ANCA are seen in Wegner's granulomatosis and Polyarteritis nodosa, which are two types of vascular diseases as well right? In fact they are also result in inflammation of the vessels don't they?

I want to know if they are just being broad with the term ANA and are they using ANCA to be more specific.

From the sound of the words, the first one sounds like the antibodies are made for a component OUTSIDE the Neutrophil, and ANCA sounds like the antibodies are made for antigens INSIDE the Neutrophil.

Please help with this clarification.

acintya
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08/29/07 - 12:18 PM

Hi LilInjn, my preliminary understanding:

ANA = Anti-nuclear antibodies: directed against nuclear antigens. They are one of the hallmarks of an autoimmune disease. They can be broadly grouped into four categories.

1. Antibodies to DNA
2. Antibodies to histone
3. Antibodies to nonhistone proteins bound to RNA
4. Antibodies to nucleolar antigens

And you are right about the pANCA and cANCA: Anti-Neutrophil Cytoplasmic Antibodies

p-ANCA Ab: Poly Arteritis Nodosa and a high association with Hep B surface Ag

c-ANCA Ab: Wegener's Granulomatosis

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LilInjnDatCould
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09/01/07 - 10:54 AM

Thank you, Acintya for your detailed explaination. Wow, other folks don't really respond on these subject forums! I guess i need to post my questions in the support forum next time!

tompat
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09/04/07 - 01:22 AM

and i think p-ANCA is also present in microscopic polyangitis and churg strauss !

LilInjnDatCould
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09/09/07 - 05:08 PM

Thank you, tompat for your input.

I sent this same question to Dr. Raymon and he sent me back the following answer.

Antineutrophil antibodies are autoantibodies against antigens found in neutrophils. When doing immunofluorescence, there are two patterns: IF segregated around the nucleus and IF throughout the cytoplasm. Note that in both cases, the location of the fluorescence is inside the netrophil, in its cytoplasm. This in turn gives rise to Perinuclear vs Cytoplasmic antineutrophil antibodies, or P-ANCA and C-ANCA. The antigens are well known, remember, myeloperoxidase and proteinase 3, respectively! They are also markers of the vasculitides you mention, PAN and Wegener's, respectively.

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