CD40LG and pneumocystosis: Two further studies that examined serologic responses in hospitalized patients with PCP, and showed elevated NO2, and PM10 were independently associated with impaired IgM responses to P. jirovecii major surface glycoprotein (Msg) constructs in serum [42], and that there was an impaired IgA response to P. jirovecii Msg in bronchoscopic lavage (BAL) fluid that was associated with increased ambient ozone exposure.