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K M Cipolone

Publications and source records attributed to K M Cipolone.

6 recordsLinked to original sources
PubMed2001

Detection of granulocyte antibodies by flow cytometry without the use of pure granulocyte isolates.

Established methods used to detect serum antibodies to granulocytes require the isolation of granulocytes. Flow cytometric analysis of granulocytes with monoclonal antibodies eliminates the need for granulocyte isolation. The purpose of this study was to develop a method to evaluate reactions of antibodies to granulocytes without separating granulocytes from other leukocytes. Three screening cell samples for granulocyte antibody detection were prepared from whole-blood samples in which the red blood cells (RBCs) were lysed and remaining leukocytes tested against sera at 4 degrees C. Binding of human alloantibodies to the screening cells was determined by flow cytometric analysis using phycoerythrin-conjugated antibody to human immunoglobulin. Forward and side scatter were used to analyze granulocytes separately from other leukocytes. The assay was validated by testing granulocytes with reference alloantibodies directed to NA1, NA2, 5b, and Mart antigens. Samples from 32 patients were tested, and the results of the assays were compared with the results of testing the samples in a granulocyte immunofluorescence (GIF) assay performed by a reference laboratory. In the whole-blood flow cytometric (WBFC) assay the mean fluorescence intensities of reference antisera with antigen-positive cells, expressed in arbitrary units, were anti-NA1 = 48 to 221, anti-NA2 = 24 to 69, anti-5b = 13 to 57, and anti-Mart = 42 to 72. In contrast, the mean fluorescence intensity of type AB-negative control sera ranged from 3 to 11. Of the 32 patient sera tested, 23 were positive (range = 12 to 56) and 9 were negative (range = 3 to 10). When compared with the results obtained by the reference laboratory, 27 sera were concordant between the WBFC and the GIF assays. Four of the samples were positive in WBFC (range = 11 to 31) and negative in GIF and one sample was negative in WBFC (range = 5 to 6) and positive in GIF. Leukocytes prepared from whole blood after lysis of RBCs can be used in flow cytometric analysis to detect granulocyte alloantibodies. The results of testing for granulocyte antibodies with this assay were similar to results of testing sera in GIF. Further comparative studies are indicated to confirm findings and explain the discordant results.

Journal Article↗
PubMed2000

Detection of HLA antibodies by using flow cytometry and latex beads coated with HLA antigens.

BACKGROUND: Detection of HLA class I antibodies in sera is needed in various clinical situations. The standard method for detecting HLA class I antibodies is the complement-dependent lymphocytotoxicity (CDC) assay, but solid-phase assays are now available. STUDY DESIGN AND METHODS: This study assessed the ability of a flow cytometric assay using latex beads coated with HLA class I antigens to detect HLA class I-specific antibodies. The CDC assay was compared with the pooled-bead assay for the detection of HLA class I antibodies. Thirty-one randomly selected serum samples previously tested by CDC assay were tested with pooled beads and analyzed by flow cytometry. Twenty-seven additional serum samples, chosen by clinical criteria and CDC assay results, were tested against the pooled beads. Next, samples from six patients from whom three or more serum samples were drawn on consecutive days were tested with both methods. Finally, serum samples that were proved positive by both methods were tested with selected beads coated with antigens from a single person. RESULTS: Among the randomly selected serum samples, there was 90-percent agreement between the two assays. There was 96-percent agreement between the two assays of the 27 samples that were selected by clinical criteria and CDC assay results. Testing the sera with individual beads suggested that the HLA class I antibodies react with beads expressing the corresponding HLA antigen and beads expressing antigens in the same cross-reactive group. CONCLUSION: The pooled-bead assay can be used as an alternative method for detecting HLA class I antibodies. However, if the specificity of the HLA class I antibody is required, another assay must be used.

Antibodies↗
PubMed1999

Biotinylation modifies red cell antigens.

BACKGROUND: Chemical biotinylation of red cell membranes may be useful for several clinical applications, including red cell survival studies. STUDY DESIGN AND METHODS: To examine the possible effects of biotinylation on red cell antigens, standard hemagglutination assays were performed on matched sets of control and biotinylated red cells. The red cells were biotinylated at a final concentration of 2.0 pg of sulfo-N-hydroxysuccinimide-biotin per cell, and antigen-negative cells were directly compared to antigen-positive cells when possible. The hemagglutination assays were graded in a blinded fashion. Forty-one red cell antigens from 21 of the 23 established blood group systems were tested. RESULTS: Hemagglutination based upon antibody binding to A, A1, M, N, S, s, P1, D, C, E, c, e, C(w), Lu(b), K, k, Kp(b), Le(a), Le(b), Fy(a), Fy(b), Jk(a), Jk(b), Di(a), Wr(a), Wr(b), Yt(a), Xg(a), Sc1, Do(b), Co(a), Ch, H, Ge2, Cr(a), Kn(a), I, and P was not affected by biotinylation. Unexpectedly, the hemagglutination of Di(b+) and LW(a+) red cells was blocked after biotinylation. Conversely, MH04 monoclonal anti-A agglutinated red cells expressing B only after biotinylation. BIRMA-1 monoclonal anti-A and polyclonal anti-A from sera did not agglutinate the biotinylated B red cells. CONCLUSION: Biotinylation of human red cells specifically modified their antigenicity, as measured by standard hemagglutination assays.

Biotinylation↗
PubMed1999

Evaluation of the gel system for ABO grouping and D typing.

BACKGROUND: The gel agglutination assay has been approved by the Food and Drug Administration as an alternative to the tube assay for the detection of red cell antibodies. It has also been approved recently by the Food and Drug Administration for ABO blood grouping and D typing. STUDY DESIGN AND METHODS: Tube and gel agglutination assays were compared for ABO grouping and D typing of 100 donor and 100 patient specimens. ABO grouping of 14 specimens of known ABO groups and D typing of 10 specimens with weak D were also compared. When antigen typing or isohemagglutinin results differed, gel testing was repeated by the use of modified incubation times, reagent or specimen volumes, and red cell concentrations. RESULTS: ABO grouping and D typing in all patient and donor specimens concurred. B isohemagglutinins were not detected in seven group A specimens. Six of seven discrepancies were resolved when gel tests were incubated at room temperature with increased serum or plasma volume. Weak D was detected in all 10 specimens tested by both assays. When weak A and/or B were tested with monoclonal antibody reagents, the correct phenotypes were identified in 9 specimens by gel assay and in 10 by tube assay. Using human antisera, 6 specimens were correctly phenotyped by gel assay and 7 by tube assay. CONCLUSION: The gel assay performed as well as the tube assay in detection of A, B, and D, but the tube assay was slightly better at detecting B isohemagglutinins. The gel assay can be used in place of the tube assay for ABO blood grouping and D typing.

ABO Blood-Group System↗
PubMed1998

Comparison of tube and gel red blood cell agglutination techniques in detecting chimeras after major ABO-mismatched allogeneic hematopoietic stem cell transplantation.

We compared the ability of tube and gel red blood cell (RBC) agglutination techniques to follow erythroid engraftment in a patient who received a major ABO-mismatched peripheral blood stem cell transplant and bone marrow transplant. Tube and gel RBC agglutination techniques were used to detect mixed-field reactivity in cell mixtures containing A/O and c+/c- RBCs and the ability of these two technologies to detect RBC chimeras were compared. We detected c+ RBCs in c+/c- RBC populations microscopically at 1% by the tube RBC agglutination technique, but not until 10% by the gel technique. Group A RBCs in A/O RBC populations were detected at 10% by both techniques. In the patient studied, group A RBCs and c+ RBCs were detected on Days 20 and 14, respectively, with the tube RBC agglutination technique, but neither marker was detected until Day 26 with the gel technique. Tube and gel RBC agglutination techniques comparably identified ABO mixed fields. Although the tube RBC agglutination technique showed greater sensitivity than the gel technique in detecting the c antigen, the gel technique was easier to use and allowed more reliable interpretation of mixed fields by the technologist.

Journal Article↗