You can be HIV negative but still have some problems that keep your immune system suppressed. If you took Antibiotics , that is the main cause. Antibiotics kill the friendly flora and depress the immune system. Lack of good flora is a cause of immune suppression and candida overgrowth. Allergy, Parasites, Heavy Metal Toxicity, food intolerances and Viruses toward the immune system to create antibodies and overload it. Cell-mediated immunity will be deficient if the immune system is working toward to the Th2 side. The immune system is an army with limited soldiers. You can not have all of them fighting a battle because the opportunistics, like candida, get advantage of that. You need to balance the immune system.