Table 4.

IgA anti-citrullinated HSP90 profiles—BALF versus serum.

	citHSP90αa		citHSP90βa		PP 1C-5Cb		PP 1-5b		PP 6C-10Cb		PP 6–10b		Peptides		Tet Toxoidc
	BAL	S	BAL	S	BAL	S	BAL	S	BAL	S	BAL	S	BAL	S	BAL	S
RA-ILD
	−	NA	1+	−	−	NA	−	NA	−	NA	−	NA	NA	NA	−	+/−
	−	NA	2+	−	2+	−	−	−	−	−	−	−	2C,3C	−	+/−	4+
	−	NA	1+	−	1+	1+	1–2+	1+	−	−	−	−	5,5C	5,5C	1+	3+
RA-no ILD
	−	NA		NA	3+		3+			NA		NA	5,5C		2+	4+

^aPositive responses based on OD₄₅₀ threshold > 2 SD above the mean for healthy control subjects, using recombinant citrullinated HSP90α or citrullinated HSP90β as substrate antigen (1 µg/ml); numerical grading of responses determined by relative ratios of OD₄₅₀ readings to those of BALF sample 138 (1 + = relative OD₄₅₀ 1.0–2.0, 2+ = relative OD₄₅₀ > 2.0), as shown in Fig. 2A.

^bPositive responses based on OD₄₅₀ threshold > 2 SD above the mean for healthy control subjects, using peptide pools (PP) consisting of 1C-5C or 6C-10C (5 peptides/pool, each at 0.2 µg/ml) as substrate antigens; numerical grading of responses again determined by relative ratios of OD₄₅₀ readings to those of serum sample 138 (1 + = relative OD₄₅₀ 1.0–2.0, 2+ = relative OD₄₅₀ 2.0–3.0, 3+ = relative OD₄₅₀ > 3.0 (Fig. 2B)).

^cRelative IgG anti-tetanus toxoid antibody titer (0 = OD₄₅₀ < 0.25, +/− = OD₄₅₀ 0.25–0.5, 1 + = OD₄₅₀ 0.5–1.0, 2+ = OD₄₅₀ 1.0–1.5, 3+ = OD₄₅₀ 1.5–2.0, 4+ = OD₄₅₀ > 2.0).

NA = not assessed.

= + BALF, −serum; = +BALF, inverted serum peptide profile; = +BALF, +serum, TT_S > TT_BAL; = +BALF, +serum, TT_S = TT_BAL.