A spokesperson for the Muslim Brotherhood's Freedom and Justice Party (FJP) has rejected rumours linking the group with the mass food poisoning of Al-Azhar students.
The Brotherhood was involved in the incident to discredit Al-Azhar's Grand Imam Ahmed El-Tayeb and have him replaced with a Brotherhood ally, the rumours claim.
"No members of the [Muslim Brotherhood] or the FJP have blamed the incident on [Al-Azhar's Grand Imam Ahmed] El-Tayeb," Mourad Ali said on Tuesday.
Such rumours were an attempt to drive a wedge between the Brotherhood and El-Tayeb, he added.
The Islamist group has been accused by opponents of seeking to appoint allies into senior positions throughout the country's institutions.
Muslim Brotherhood spokesperson Ahmed Aref also rejected the rumours.
Under the constitution, the grand imam cannot be removed from office, Aref added.
Thousands of Al-Azhar University students marched on Wednesday afternoon from the campus in Nasr City to Al-Azhar Sheikhdom in Cairo's Darrasa district. They chanted against the university's management and president who they accuse of negligence.
Al-Azhar students will also stage protests on Wednesday at the university's branches in Assiut, Mansoura, Alexandria and Tanta, student union member Osama Zeid said.
"The student union backs demands to remove Grand Imam El-Tayeb and the university president," Zeid told Al-Ahram Arabic news website on Wednesday.
University faculty members will hold a meeting on Wednesday afternoon in solidarity with the protesting students, Zeid added.
In a bid to contain the situation, President Morsi will on Wednesday meet with a ten-member student delegation, Al-Ahram Arabic news website reported.
Around 500 students were hospitalised on Monday after eating at a cafeteria on the Al-Azhar campus.
Shortly afterwards, hundreds of angry students gathered at the university's dormitory building to protest what they said was serious negligence by management.
On Tuesday, hundreds of students broke into the university headquarters in Cairo's Nasr City. Some of the protesting students demanded the resignation of the university president, Osama El-Abd.
President Mohamed Morsi visited some of the ill students in hospital on Tuesday morning.
The last of the students were discharged from hospital on Wednesday, an official at Al-Azhar said.