AEGiS-11IAC: A rapid flow cytometric method detects reduced T cell proliferative responses to phytohaemagglutinin (PHA) in HIV-infected subjects.

11th International AIDS Conference


Vancouver, British Columbia — July 7-12, 1996

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A rapid flow cytometric method detects reduced T cell proliferative responses to phytohaemagglutinin (PHA) in HIV-infected subjects.

Int Conf AIDS 1996 Jul 7-12; 11:439 (abstract no. Pub.A.1008)
Trickett AE, Cameron B, Kwan YL; Southpath, St George Hospital, Sydney, NSW, Australia. Fax: +61-2-350-3942.

OBJECTIVE: Using a rapid, whole blood, flow cytometric method this study aimed to compare the mitogen-induced T lymphocyte proliferative response of HIV-infected patients with that of healthy uninfected controls.

METHODS: Blood samples from 12 uninfected male subjects (mean CD4/microliter = 923, range 790 - 1188) and 18 HIV-infected male patients (mean CD4/microliter = 396, range 4 - 862) were subjected to red cell lysis, then cultured for 18 hours in the presence or absence of PHA. Cells were subsequently stained with monoclonal antibodies recognising the CD3 (T lymphocyte) and CD69 (early activation) antigens, fixed and analysed by 2 colour flow cytometry. Percent proliferative response was calculated as: [stimulated (CD69+ T cells/total T cells) - unstimulated (CD69+ T cells/total T cells)] x 100. A moderate correlation (r2 = 0.69) has been observed between results obtained by this technique and the standard method utilising 3H-thymidine incorporation.

RESULTS: Samples from the HIV-infected patients yielded a T cell proliferative response of 61 plus or minus 13% (mean plus or minus 1SD) which was significantly lower than the response from control subjects (82 plus or minus 7%; p is less than 0.01, t test). A moderate correlation was seen between CD4 count and PHA proliferative response in HIV-infected patients with a CD4 count greater than 200/microliter (r2 = 0.587). However, no such correlation was demonstrated in patients with a CD4 count less than 200/microliter (r2 = 0.0001).Of the 18 HIV-infected patients, 14 with asymptomatic disease showed significantly higher proliferation responses (64 plus or minus 11%) than 4 patients with ARC (proliferation response = 51 plus or minus 15%, p is less than 0.05).

CONCLUSION: By using a whole blood flow cytometric method, T lymphocytes from both asymptomatic HIV-infected and ARC patients were shown to have a significantly reduced proliferative response to PHA compared to uninfected subjects. This finding is contrary to most previous studies using methods based on 3H-thymidine incorporation where normal responses are generally observed in asymptomatic patients. This assay may prove to be more sensitive than the standard methods and hence be particularly useful for rapid assessment of immune function in patients with HIV-infection.

Keywords: AEGIS, Phytohemagglutinins, T-Lymphocytes, Antigens, Differentiation, T-Lymphocyte, Antigens, CD3, Antigens, CD, HIV Infections, Mitogens, Flow Cytometry, Antigens, CD4, CD4 Lymphocyte Count, AIDS-Related Complex, Leu-23 antigen, Male, Human, ICA11KWDaegis,phytohemagglutinins,t-lymphocytes,antigens,differentiation,t-lymphocyte,antigens,cd3,antigens,cd,hivinfections,mitogens,flowcytometry,antigens,cd4,cd4lymphocytecount,aids-relatedcomplex,leu-23antigen,male,human,ica11

960707
PubA1008

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